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Comparative study of the growth, stress status and reproductive capabilities of four wild-type zebrafish ( Danio rerio ) lines

Zebrafish are widely used in various research fields and to fulfil the diverse research needs, numerous zebrafish lines are available, each with a unique domestication background, potentially resulting in intr...

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PTN from Leydig cells activates SDC2 and modulates human spermatogonial stem cell proliferation and survival via GFRA1

Spermatogonial stem cells (SSCs) are essential for the maintenance and initiation of male spermatogenesis. Despite the advances in understanding SSC biology in mouse models, the mechanisms underlying human SSC...

The effect of CGRP and SP and the cell signaling dialogue between sensory neurons and endothelial cells

Increasing evidences demonstrate the role of sensory innervation in bone metabolism, remodeling and repair, however neurovascular coupling in bone is rarely studied. Using microfluidic devices as an indirect c...

Mouse testicular macrophages can independently produce testosterone and are regulated by Cebpb

Testicular macrophages (TM) have long been recognized for their role in immune response within the testicular environment. However, their involvement in steroid hormone synthesis, particularly testosterone, ha...

Fruit sugar hub: gene regulatory network associated with soluble solids content (SSC) in Prunus persica

Chilean peach growers have achieved worldwide recognition for their high-quality fruit products. Among the main factors influencing peach fruit quality, sweetness is pivotal for maintaining the market's compet...

Antimicrobial activity of compounds identified by artificial intelligence discovery engine targeting enzymes involved in Neisseria gonorrhoeae peptidoglycan metabolism

Neisseria gonorrhoeae (Ng) causes the sexually transmitted disease gonorrhoea. There are no vaccines and infections are treated principally with antibiotics. However, gonococci rapidly develop resistance to every...

Hormonal influence: unraveling the impact of sex hormones on vascular smooth muscle cells

Sex hormones play a pivotal role as endocrine hormones that exert profound effects on the biological characteristics and vascular function of vascular smooth muscle cells (VSMCs). By modulating intracellular s...

Unraveling the impact of hyperleptinemia on female reproduction: insights from transgenic pig model

Infertility is a growing global health concern affecting millions of couples worldwide. Among several factors, an extreme body weight adversely affects reproductive functions. Leptin is a well-known adipokine ...

Deciphering genetic and nongenetic factors underlying tumour dormancy: insights from multiomics analysis of two syngeneic MRD models of melanoma and leukemia

Tumour dormancy, a resistance mechanism employed by cancer cells, is a significant challenge in cancer treatment, contributing to minimal residual disease (MRD) and potential relapse. Despite its clinical impo...

Genetic deletion of ITIH5 leads to increased development of adipose tissue in mice

Adipocytokines play a pivotal role in maintaining adipose tissue homeostasis by regulating cellular metabolism, proliferation, differentiation, and secretory activity. These soluble factors are relevant compon...

Inhibition of forward and reverse transport of Ca 2+ via Na + /Ca 2+ exchangers (NCX) prevents sperm capacitation

While calcium is known to play a crucial role in mammalian sperm physiology, how it flows in and out of the male gamete is not completely understood. Herein, we investigated the involvement of Na + /Ca 2+ exchangers...

Selective disruption of synaptic NMDA receptors of the hippocampal trisynaptic circuit in Aβ pathology

Synaptic dysfunction is an early feature in Alzheimer’s disease (AD) pathogenesis and a major morphological correlate of memory deficits. Given the main synaptic location of N -methyl-D-aspartate receptors (NMDARs...

Placental growth factor mediates pathological uterine angiogenesis by activating the NFAT5-SGK1 signaling axis in the endometrium: implications for preeclampsia development

After menstruation the uterine spiral arteries are repaired through angiogenesis. This process is tightly regulated by the paracrine communication between endometrial stromal cells (EnSCs) and endothelial cell...

Dissecting reactive astrocyte responses: lineage tracing and morphology-based clustering

Brain damage triggers diverse cellular and molecular events, with astrocytes playing a crucial role in activating local neuroprotective and reparative signaling within damaged neuronal circuits. Here, we inves...

Neuronal repair after spinal cord injury by in vivo astrocyte reprogramming mediated by the overexpression of NeuroD1 and Neurogenin-2

As a common disabling disease, irreversible neuronal death due to spinal cord injury (SCI) is the root cause of functional impairment; however, the capacity for neuronal regeneration in the developing spinal c...

PvMYB60 gene, a candidate for drought tolerance improvement in common bean in a climate change context

Common bean ( Phaseolus vulgaris ) is one of the main nutritional resources in the world, and a low environmental impact source of protein. However, the majority of its cultivation areas are affected by drought and...

Enhancing adipose tissue functionality in obesity: senotherapeutics, autophagy and cellular senescence as a target

Obesity, a global health crisis, disrupts multiple systemic processes, contributing to a cascade of metabolic dysfunctions by promoting the pathological expansion of visceral adipose tissue (VAT). This expansi...

Effects of a supplemented diet containing 7 probiotic strains (Honeybeeotic) on honeybee physiology and immune response: analysis of hemolymph cytology, phenoloxidase activity, and gut microbiome

In this study, a probiotic mixture (Honeybeeotic) consisting of seven bacterial strains isolated from a unique population of honeybees ( Apis mellifera ligustica ) was used. That honeybee population was located in ...

Uncovering the role of the subcommissural organ in early brain development through transcriptomic analysis

The significant role of embryonic cerebrospinal fluid (eCSF) in the initial stages of brain development has been thoroughly studied. This fluid contains crucial molecules for proper brain development such as m...

A preclinical mice model of multiple sclerosis based on the toxin-induced double-site demyelination of callosal and cerebellar fibers

Multiple sclerosis (MS) is an irreversible progressive CNS pathology characterized by the loss of myelin (i.e. demyelination). The lack of myelin is followed by a progressive neurodegeneration triggering sympt...

Renoprotective effect of a novel combination of 6-gingerol and metformin in high-fat diet/streptozotocin-induced diabetic nephropathy in rats via targeting miRNA-146a, miRNA-223, TLR4/TRAF6/NLRP3 inflammasome pathway and HIF-1α

MiRNA-146a and miRNA-223 are key epigenetic regulators of toll-like receptor 4 (TLR4)/tumor necrosis factor-receptor-associated factor 6 (TRAF6)/NOD-like receptor family pyrin domain-containing 3 (NLRP3) infla...

Unveiling a novel memory center in human brain: neurochemical identification of the nucleus incertus , a key pontine locus implicated in stress and neuropathology

The nucleus incertus (NI) was originally described by Streeter in 1903, as a midline region in the floor of the fourth ventricle of the human brain with an ‘unknown’ function. More than a century later, the neuro...

Chrysin-loaded PEGylated liposomes protect against alloxan-induced diabetic neuropathy in rats: the interplay between endoplasmic reticulum stress and autophagy

Diabetic neuropathy (DN) is recognized as a significant complication arising from diabetes mellitus (DM). Pathogenesis of DN is accelerated by endoplasmic reticulum (ER) stress, which inhibits autophagy and co...

Lead and calcium crosstalk tempted acrosome damage and hyperpolarization of spermatozoa: signaling and ultra-structural evidences

Exposure of humans and animals to heavy metals is increasing day-by-day; thus, lead even today remains of significant public health concern. According to CDC, blood lead reference value (BLRV) ranges from 3.5 ...

Molecular hydrogen promotes retinal vascular regeneration and attenuates neovascularization and neuroglial dysfunction in oxygen-induced retinopathy mice

Retinopathy of Prematurity (ROP) is a proliferative retinal vascular disease occurring in the retina of premature infants and is the main cause of childhood blindness. Nowadays anti-VEGF and retinal photocoagu...

Retraction Note: Tridax procumbens flavonoids promote osteoblast differentiation and bone formation

Exercise reduces physical alterations in a rat model of fetal alcohol spectrum disorders.

Prenatal alcohol exposure (PAE) has serious physical consequences for children such as behavioral disabilities, growth disorders, neuromuscular problems, impaired motor coordination, and decreased muscle tone....

Loss of protein tyrosine phosphatase receptor delta PTPRD increases the number of cortical neurons, impairs synaptic function and induces autistic-like behaviors in adult mice

The brain cortex is responsible for many higher-level cognitive functions. Disruptions during cortical development have long-lasting consequences on brain function and are associated with the etiology of brain...

Inhibition of astroglial hemichannels prevents synaptic transmission decline during spreading depression

Spreading depression (SD) is an intriguing phenomenon characterized by massive slow brain depolarizations that affect neurons and glial cells. This phenomenon is repetitive and produces a metabolic overload th...

Correction: Conformational characterization of the mammalian-expressed SARS-CoV-2 recombinant receptor binding domain, a COVID-19 vaccine

The original article was published in Biological Research 2023 56 :22

The current insights of mitochondrial hormesis in the occurrence and treatment of bone and cartilage degeneration

It is widely acknowledged that aging, mitochondrial dysfunction, and cellular phenotypic abnormalities are intricately associated with the degeneration of bone and cartilage. Consequently, gaining a comprehens...

The crucial role of HFM1 in regulating FUS ubiquitination and localization for oocyte meiosis prophase I progression in mice

Helicase for meiosis 1 (HFM1), a putative DNA helicase expressed in germ-line cells, has been reported to be closely associated with premature ovarian insufficiency (POI). However, the underlying molecular mec...

Distinct properties of putative trophoblast stem cells established from somatic cell nuclear-transferred pig blastocysts

Genetically modified pigs are considered ideal models for studying human diseases and potential sources for xenotransplantation research. However, the somatic cell nuclear transfer (SCNT) technique utilized to...

Electroacupuncture attenuates neuropathic pain via suppressing BIP-IRE-1α-mediated endoplasmic reticulum stress in the anterior cingulate cortex

Studies have suggested that endoplasmic reticulum stress (ERS) is involved in neurological dysfunction and that electroacupuncture (EA) attenuates neuropathic pain (NP) via undefined pathways. However, the rol...

Effect of Cannabis sativa L. extracts, phytocannabinoids and their acetylated derivates on the SHSY-5Y neuroblastoma cells’ viability and caspases 3/7 activation

There is a need for novel treatments for neuroblastoma, despite the emergence of new biological and immune treatments, since refractory pediatric neuroblastoma is still a medical challenge. Phyto cannabinoids ...

The hepatoprotective effect of 4-phenyltetrahydroquinolines on carbon tetrachloride induced hepatotoxicity in rats through autophagy inhibition

The liver serves as a metabolic hub within the human body, playing a crucial role in various essential functions, such as detoxification, nutrient metabolism, and hormone regulation. Therefore, protecting the ...

Connexin channels and hemichannels are modulated differently by charge reversal at residues forming the intracellular pocket

Members of the β-subfamily of connexins contain an intracellular pocket surrounded by amino acid residues from the four transmembrane helices. The presence of this pocket has not previously been investigated i...

IDH1 mutation produces R-2-hydroxyglutarate (R-2HG) and induces mir-182-5p expression to regulate cell cycle and tumor formation in glioma

Mutations in isocitrate dehydrogenase 1 and 2 ( IDH1 and IDH2 ), are present in most gliomas. IDH1 mutation is an important prognostic marker in glioma. However, its regulatory mechanism in glioma remains incomplet...

Therapeutic potential of oleic acid supplementation in myotonic dystrophy muscle cell models

We recently reported that upregulation of Musashi 2 (MSI2) protein in the rare neuromuscular disease myotonic dystrophy type 1 contributes to the hyperactivation of the muscle catabolic processes autophagy and...

Dorsal root ganglion-derived exosomes deteriorate neuropathic pain by activating microglia via the microRNA-16-5p/HECTD1/HSP90 axis

The activated microglia have been reported as pillar factors in neuropathic pain (NP) pathology, but the molecules driving pain-inducible microglial activation require further exploration. In this study, we in...

MicroRNA-721 regulates gluconeogenesis via KDM2A-mediated epigenetic modulation in diet-induced insulin resistance in C57BL/6J mice

Aberrant gluconeogenesis is considered among primary drivers of hyperglycemia under insulin resistant conditions, with multiple studies pointing towards epigenetic dysregulation. Here we examine the role of mi...

Combined transcriptomics and proteomics unveil the impact of vitamin C in modulating specific protein abundance in the mouse liver

Vitamin C (ascorbate) is a water-soluble antioxidant and an important cofactor for various biosynthetic and regulatory enzymes. Mice can synthesize vitamin C thanks to the key enzyme gulonolactone oxidase (Gul...

Novel role of LLGL2 silencing in autophagy: reversing epithelial-mesenchymal transition in prostate cancer

Prostate cancer (PCa) is a major urological disease that is associated with significant morbidity and mortality in men. LLGL2 is the mammalian homolog of Lgl. It acts as a tumor suppressor in breast and hepati...

Rapid development and mass production of SARS-CoV-2 neutralizing chicken egg yolk antibodies with protective efficacy in hamsters

Despite the record speed of developing vaccines and therapeutics against the SARS-CoV-2 virus, it is not a given that such success can be secured in future pandemics. In addition, COVID-19 vaccination and appl...

High-fat diet, microbiome-gut-brain axis signaling, and anxiety-like behavior in male rats

Obesity, associated with the intake of a high-fat diet (HFD), and anxiety are common among those living in modern urban societies. Recent studies suggest a role of microbiome-gut-brain axis signaling, includin...

General regulatory factors exert differential effects on nucleosome sliding activity of the ISW1a complex

Chromatin dynamics is deeply involved in processes that require access to DNA, such as transcriptional regulation. Among the factors involved in chromatin dynamics at gene regulatory regions are general regula...

Establishment of primary prostate epithelial and tumorigenic cell lines using a non-viral immortalization approach

Research on prostate cancer is mostly performed using cell lines derived from metastatic disease, not reflecting stages of tumor initiation or early progression. Establishment of cancer cell lines derived from...

The effect of diabetes mellitus on differentiation of mesenchymal stem cells into insulin-producing cells

Diabetes mellitus (DM) is a global epidemic with increasing incidences. DM is a metabolic disease associated with chronic hyperglycemia. Aside from conventional treatments, there is no clinically approved cure...

Control of astrocytic Ca 2+ signaling by nitric oxide-dependent S-nitrosylation of Ca 2+ homeostasis modulator 1 channels

Astrocytes Ca 2+ signaling play a central role in the modulation of neuronal function. Activation of metabotropic glutamate receptors (mGluR) by glutamate released during an increase in synaptic activity triggers ...

Increased levels and activation of the IL-17 receptor in microglia contribute to enhanced neuroinflammation in cerebellum of hyperammonemic rats

Patients with liver cirrhosis may show minimal hepatic encephalopathy (MHE) with mild cognitive impairment and motor incoordination. Rats with chronic hyperammonemia reproduce these alterations. Motor incoordi...

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Biological Research

ISSN: 0717-6287

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Here’s Why Birds Look So Goofy When They Run

Looking silly when they run saves birds energy—and some dinosaurs may have done the same

Meghan Bartels

The Surprising Challenges of Using Prehistoric Diversity to Understand Life Today

The incompleteness of the fossil record complicates efforts to figure out how life on Earth is faring today

Asher Elbein

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Stunning Bird Photographs Showcase Incredible Views of Life on the Wing

Quirky perspectives, separated lovebirds and a tobogganing penguin star in 2024 winners of the world’s largest bird photography competition

Cave Fish Adolescence Means Sprouting Taste Buds in Weird Places

Cave fish develop taste buds on their head and below their chin—and even in humans, taste cells grow in truly unexpected locations

Elizabeth Anne Brown

Here’s What the ‘Manosphere’ Gets Wrong about Cuckoldry

In online forums the term “cuck” has become synonymous with “sucker” and “loser.” But this use distorts its history and meaning, creating a baseless moral panic that harms both women and science

Brooke Scelza

Quantum ‘Ghost Imaging’ Reveals the Dark Side of Plants

Entanglement lets researchers watch plants in action without disruptive visible light

Rachel Berkowitz

Mystery of Deep-Ocean ‘Biotwang’ Sound Has Finally Been Solved

A strange sound dubbed “biotwang” was first heard bouncing around the Mariana Trench 10 years ago, and scientists have finally figured out where it comes from

Melissa Hobson

Chickadees Show How Species Boundaries Can Shift and Blur

When different chickadee species meet, they sometimes choose each other as mates—with surprising results

Rebecca Heisman

Caterpillars Sense Hungry Wasps’ Electrical Field

Predators’ electricity gives caterpillars an early warning

Gennaro Tomma

Scientists Make Living Mice’s Skin Transparent with Simple Food Dye

New research harnessed the highly absorbent dye tartrazine, used as the common food coloring Yellow No. 5, to turn tissues in living mice clear—temporarily revealing organs and vessels inside the animals

Lauren J. Young

Do Cats Really Hate Water?

Not all cats are hydrophobic

The Earliest Known Animal Sex Chromosome is 480 Million Years Old

The octopus sex chromosome appears to have been maintained over hundreds of millions of years, making it the most ancient of such chromosomes in animals

Viviane Callier

September 19, 2024

Engineering chloroplasts

Plastids are important organelles that can be engineered to enhance photosynthetic and metabolic traits in plants. Chonprakun Thagun, Masaki Odahara, Yutaka Kodama and Keiji Numata identify a chloroplast-targeting peptide that is highly efficient in delivering biologically functional proteins to plastids in plants.

Image credit: Chonprakun Thagun and Keiji Numata

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Research Article

DNA methylation helps plant pathogen evolution

Do epigenetic changes contribute to long-term bacterial adaptation? Rekha Gopalan-Nair, Aurore Coissac, Alice Guidot and co-workers show that changes in DNA methylation enable rapid adaptation of the major agricultural bacterial pathogen Ralstonia pseudosolanacearum to novel hosts, stable over 100 generations.

Image credit: pbio.3002792

Recently Published Articles

• Identification of a highly efficient chloroplast-targeting peptide for plastid engineering
• Diverse signatures of convergent evolution in cactus-associated yeasts
• Human brain state dynamics are highly reproducible and associated with neural and behavioral features

Current Issue August 2024

One   rhoptry or two?

Plasmodium parasites have a pair of unique organelles called rhoptries that are made anew every replicative cycle. David Anaguano, Vasant Muralidharan and colleagues show that the RON11 protein triggers de novo biogenesis of the second rhoptry and is important for parasite invasion of erythrocytes.

Image credit: pbio.3002801

Functional network modules in the developing human brain 

Network modules in the human brain have mostly been considered to be non-overlapping during development. This neuroimaging study of functional connectome maturation during childhood and adolescence in over 300 children, by Tianyuan Lei, Xuhong Liao, Yong He and co-authors, reveals its overlapping architecture, which is associated with structural properties.

Image credit: pbio.3002653

Methods and Resources

Tracking organelles

Organelles have unique structures and molecular composition, but traditional methods have failed to reflect their heterogeneity and ontogenetic dynamics. Yoshitaka Kurikawa, Ikuko Koyama-Honda, Noboru Mizushima and co-workers introduce a multi-parametric, fluorescence spectroscopy method that allows simultaneous visualization of a wide array of organelles in different maturation states.

Image credit: pbio.3002777

A new tree for opisthokonts

Opisthokonta is the major lineage that includes animals, fungi, and their unicellular relatives, but some ancient divergences remain contentious. Hongyue Liu, Antonis Rokas, Yuanning Li and colleagues present a genome-scale phylogeny and establish the geological timeline of opisthokont diversification.

Image credit: Hongyue Liu

Integrating gene expression with neuroimaging data

Integrating neuroimaging and molecular brain data across people, brain regions and states can help to understand human brain individuality. Nhung Hoang, John Capra, Mikail Rubinov and co-workers present a resource that uses computational genomics to estimate genetically regulated components of gene expression and infer associations of this expression with neuroimaging and clinical phenotypes.

Image credit: pbio.3002782

Perspective

Reusable methods and protocols (PRO-MaP)

This Perspective article describes PRO-MaP, which aims to increase and improve the reporting of detailed, structured and open methods and reusable step-by-step protocols in the life sciences.

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Consensus View

New nomenclature for dengue virus

There is currently no suitable system to classify circulating dengue virus (DENV) variants. This Consensus View proposes a new nomenclature system and free online tools to identify and track lineages of potential epidemiological and/or clinical importance.

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Code sharing in biology

For those who want to share their code but don't know where to start, this Essay distils dozens of articles on reproducibility and research software, collecting the most important practical details of how to provide computational transparency even if you aren't a trained software developer.

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Fixing science: stop gaming the system

The open science movement has gained ground, but improvements to the practice of science move at a glacial pace. This Perspective explores the misaligned incentives that are hindering progress to more open, reproducible research.

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Decision making for conservation and biodiversity

Translating conservation and biodiversity research from the field into the real world is a complex problem. This collection discusses issues around economics, policy, and how to do research that answers questions that decision makers have.

Symbiosis across the tree of life

Symbiosis research has become a holistic and pervasive field with a mature theoretical basis. This collection showcases symbiotic relationships across the tree of life, exploring their evolutionary basis and underlying mechanisms.

PLOS Biology 20th Anniversary

PLOS Biology is 20 and we are celebrating with a collection that contains articles that look back at landmark studies that we published, others that look past and future, and others discussing how publishing and open science have evolved and what is to come.

Engineering plants for a changing climate

This collection explores engineering strategies to help us adapt plants to a changing climate, including breeding techniques, genome engineering, synthetic biology and microbiome engineering.

Going for green

The green collection explores biological solutions that could be applied to reduce CO2 emissions, get rid of non-degradable plastics, produce food in a sustainable manner or generate energy.

EMBO: BACNET 2024

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CSHL: Mechanisms of Aging 2024

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EMBL: defining and defeating metastasis

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Collection  12 March 2021

2020 Top 50 Life and Biological Sciences Articles

We are pleased to share with you the 50 most downloaded Nature Communications articles* in the life and biological sciences published in 2020. (Please note we have a separate collection on the Top 50 SARS-CoV-2 papers .) Featuring authors from around the world, these papers highlight valuable research from an international community.

Browse all Top 50 subject area collections here .

* Data obtained from SN Insights (based on Digital Science's Dimensions) and has been normalised to account for articles published later in the year.

Vitamin D metabolites and the gut microbiome in older men

Here, the authors investigate associations of vitamin D metabolites with gut microbiome in a cross-sectional analysis of 567 elderly men enrolled in the Osteoporotic Fractures in Men (MrOS) Study and find larger alpha-diversity correlates with high 1,25(OH)2D and high 24,25(OH)2D and higher ratios of activation and catabolism.

• Robert L. Thomas
• Lingjing Jiang
• Deborah M. Kado

The misuse of colour in science communication

The accurate representation of data is essential in science communication, however, colour maps that visually distort data through uneven colour gradients or are unreadable to those with colour vision deficiency remain prevalent. Here, the authors present a simple guide for the scientific use of colour and highlight ways for the scientific community to identify and prevent the misuse of colour in science.

• Fabio Crameri
• Grace E. Shephard
• Philip J. Heron

Effect of gut microbiota on depressive-like behaviors in mice is mediated by the endocannabinoid system

The gut microbiota may contribute to depression, but the underlying mechanism is not well understood. Here the authors use a mouse model of stress induced depression to demonstrate that behavioural changes conferred by fecal transplant from stressed to naïve mice require the endocannabinoid system.

• Grégoire Chevalier
• Eleni Siopi
• Pierre-Marie Lledo

The default network of the human brain is associated with perceived social isolation

Here, using pattern-learning analyses of structural, functional, and diffusion brain scans in ~40,000 UK Biobank participants, the authors provide population-scale evidence that the default network is associated with perceived social isolation.

• R. Nathan Spreng
• Emile Dimas
• Danilo Bzdok

Non-invasive early detection of cancer four years before conventional diagnosis using a blood test

Patients whose disease is diagnosed in its early stages have better outcomes. In this study, the authors develop a non invasive blood test based on circulating tumor DNA methylation that can potentially detect cancer occurrence even in asymptomatic patients.

• Xingdong Chen
• Jeffrey Gole

Deep learning suggests that gene expression is encoded in all parts of a co-evolving interacting gene regulatory structure

Regulatory and coding regions of genes are shaped by evolution to control expression levels. Here, the authors use deep learning to identify rules controlling gene expression levels and suggest that all parts of the gene regulatory structure interact in this.

• Christoph S. Börlin
• Aleksej Zelezniak

A systematic review of antibody mediated immunity to coronaviruses: kinetics, correlates of protection, and association with severity

Antibody mediated immunity to SARS-CoV-2 will affect future transmission and disease severity. This systematic review on antibody response to coronaviruses, including SARS-CoV-2, SARS-CoV, MERS-CoV and endemic coronaviruses provides insights into kinetics, correlates of protection, and association with disease severity.

• Angkana T. Huang
• Bernardo Garcia-Carreras
• Derek A. T. Cummings

Biomineral armor in leaf-cutter ants

Biomineral armour is known in a number of diverse creatures but has not previously been observed in insects. Here, the authors report on the discovery and characterization of high-magnesium calcite armour which overlays the exoskeletons of leaf-cutter ants.

• Chang-Yu Sun
• Cameron R. Currie

Senolytics prevent mt-DNA-induced inflammation and promote the survival of aged organs following transplantation

Organ transplantation involving aged donors is often confounded by reduced post-transplantation organ survival. By studying both human organs and mouse transplantation models, here the authors show that pretreating the donors with senolytics to reduce mitochondria DNA and pro-inflammatory dendritic cells may help promote survival of aged organs.

• Jasper Iske
• Midas Seyda
• Stefan G. Tullius

Fasting mimicking diet as an adjunct to neoadjuvant chemotherapy for breast cancer in the multicentre randomized phase 2 DIRECT trial

Preclinical evidence suggests that a fasting mimicking diet (FMD) can make cancer cells more vulnerable to chemotherapy, while protecting normal cells. In this randomized phase II clinical trial of 131 patients with HER2 negative early stage breast cancer, the authors demonstrate that FMD is safe and enhances the effects of neoadjuvant chemotherapy on radiological and pathological tumor response.

• Stefanie de Groot
• Rieneke T. Lugtenberg
• Dutch Breast Cancer Research Group (BOOG)

Aerobic microbial life persists in oxic marine sediment as old as 101.5 million years

The discovery of aerobic microbial communities in nutrient-poor sediments below the seafloor begs the question of the mechanisms for their persistence. Here the authors investigate subseafloor sediment in the South Pacific Gyre abyssal plain, showing that aerobic microbial life can be revived and retain metabolic potential even from 101.5 Ma-old sediment.

• Yuki Morono
• Fumio Inagaki

The auxin-inducible degron 2 technology provides sharp degradation control in yeast, mammalian cells, and mice

Auxin-inducible degron systems can be leaky and require high doses of auxin. Here the authors establish AID2 which uses an OsTIR1 mutant and the ligand 5-Ph-IAA to overcome these problems and establish AID-mediated target depletion in mice.

• Aisha Yesbolatova
• Yuichiro Saito
• Masato T. Kanemaki

Origin and cross-species transmission of bat coronaviruses in China

Bats are a likely reservoir of zoonotic coronaviruses (CoVs). Here, analyzing bat CoV sequences in China, the authors find that alpha-CoVs have switched hosts more frequently than betaCoVs, identify a bat family and genus that are highly involved in host-switching, and define hotspots of CoV evolutionary diversity.

• Alice Latinne
• Peter Daszak

Multivariate genomic scan implicates novel loci and haem metabolism in human ageing

Ageing phenotypes are of great interest but are difficult to study genetically, partly due to the sample sizes required. Here, the authors present a multivariate framework to combine GWAS summary statistics and increase statistical power, identifying additional loci enriched for aging.

• Paul R. H. J. Timmers
• James F. Wilson
• Joris Deelen

A microsporidian impairs Plasmodium falciparum transmission in Anopheles arabiensis mosquitoes

Mircobial symbionts of mosquitoes can affect transmission of human pathogens. Here, Herren et al . identify a microsporidian symbiont in Anopheles gambiae that impairs transmission without affecting mosquito fecundity or survival.

• Jeremy K. Herren
• Lilian Mbaisi
• Steven P. Sinkins

Gene editing and elimination of latent herpes simplex virus in vivo

Herpes simplex virus establishes lifelong latency in ganglionic neurons, which are the source for recurrent infection. Here Aubert et al. report a promising antiviral therapy based on gene editing with adeno-associated virus-delivered meganucleases, which leads to a significant reduction in ganglionic HSV loads and HSV reactivation.

• Martine Aubert
• Daniel E. Strongin
• Keith R. Jerome

A predictive index for health status using species-level gut microbiome profiling

A biologically-interpretable and robust metric that provides insight into one’s health status from a gut microbiome sample is an important clinical goal in current human microbiome research. Herein, the authors introduce a species-level index that predicts the likelihood of having a disease.

• Vinod K. Gupta
• Jaeyun Sung

Bacterial nanotubes as a manifestation of cell death

Bacterial nanotubes and other similar membranous structures have been reported to function as conduits between cells to exchange DNA, proteins, and nutrients. Here the authors provide evidence that bacterial nanotubes are formed only by dead or dying cells, thus questioning their previously proposed functions.

• Jiří Pospíšil
• Dragana Vítovská
• Libor Krásný

Gut microbiota mediates intermittent-fasting alleviation of diabetes-induced cognitive impairment

Intermittent fasting (IF) has been shown beneficial in reducing metabolic diseases. Here, using a multi-omics approach in a T2D mouse model, the authors report that IF alters the composition of the gut microbiota and improves metabolic phenotypes that correlate with cognitive behavior.

• Zhigang Liu
• Xiaoshuang Dai

Transient non-integrative expression of nuclear reprogramming factors promotes multifaceted amelioration of aging in human cells

Aging involves gradual loss of tissue function, and transcription factor (TF) expression can ameliorate this in progeroid mice. Here the authors show that transient TF expression reverses age-associated epigenetic marks, inflammatory profiles and restores regenerative potential in naturally aged human cells.

• Tapash Jay Sarkar
• Marco Quarta
• Vittorio Sebastiano

Mitochondrial TCA cycle metabolites control physiology and disease

Mitochondrial metabolites contribute to more than biosynthesis, and it is clear that they influence multiple cellular functions in a variety of ways. Here, Martínez-Reyes and Chandel review key metabolites and describe their effects on processes involved in physiology and disease including chromatin dynamics, immunity, and hypoxia.

• Inmaculada Martínez-Reyes
• Navdeep S. Chandel

A deep learning model to predict RNA-Seq expression of tumours from whole slide images

RNA-sequencing of tumour tissue can provide important diagnostic and prognostic information but this is costly and not routinely performed in all clinical settings. Here, the authors show that whole slide histology slides—part of routine care—can be used to predict RNA-sequencing data and thus reduce the need for additional analyses.

• Benoît Schmauch
• Alberto Romagnoni
• Gilles Wainrib

Circadian regulation of mitochondrial uncoupling and lifespan

Disruption of different components of molecular circadian clocks has varying effects on health and lifespan of model organisms. Here the authors show that loss of period extends life in drosophila melanogaster.

• Matt Ulgherait
• Mimi Shirasu-Hiza

Circadian control of brain glymphatic and lymphatic fluid flow

Glymphatic function is increased during the rest phase while more cerebrospinal fluid (CSF) drains directly to the lymphatic system during the active phase. The water channel aquaporin-4 supports these endogenous, circadian rhythms in CSF distribution.

• Lauren M. Hablitz
• Virginia Plá
• Maiken Nedergaard

Brain-inspired replay for continual learning with artificial neural networks

One challenge that faces artificial intelligence is the inability of deep neural networks to continuously learn new information without catastrophically forgetting what has been learnt before. To solve this problem, here the authors propose a replay-based algorithm for deep learning without the need to store data.

• Gido M. van de Ven
• Hava T. Siegelmann
• Andreas S. Tolias

Single-cell RNA-seq reveals that glioblastoma recapitulates a normal neurodevelopmental hierarchy

Glioblastoma is thought to arise from neural stem cells. Here, to investigate this, the authors use single-cell RNA-sequencing to compare glioblastoma to the fetal human brain, and find a similarity between glial progenitor cells and a subpopulation of glioblastoma cells.

• Charles P. Couturier
• Shamini Ayyadhury
• Kevin Petrecca

Deep learning for genomics using Janggu

Deep learning is becoming a popular approach for understanding biological processes but can be hard to adapt to new questions. Here, the authors develop Janggu, a python library that aims to ease data acquisition and model evaluation and facilitate deep learning applications in genomics.

• Wolfgang Kopp
• Altuna Akalin

Versatile whole-organ/body staining and imaging based on electrolyte-gel properties of biological tissues

Tissue clearing has revolutionised histology, but limited penetration of antibodies and stains into thick tissue segments is still a bottleneck. Here, the authors characterise optically cleared tissue as an electrolyte gel and apply this knowledge to stain the entirety of thick tissue samples.

• Etsuo A. Susaki
• Chika Shimizu
• Hiroki R. Ueda

Sestrins are evolutionarily conserved mediators of exercise benefits

Exercise improves metabolic health and physical condition, particularly important for health in aged individuals. Here, the authors identify that Sestrins, proteins induced by exercise, are key mediators of the metabolic adaptation to exercise and increase endurance through the AKT and PGC1a axes.

• Myungjin Kim
• Alyson Sujkowski
• Jun Hee Lee

Synergistic effect of fasting-mimicking diet and vitamin C against KRAS mutated cancers

Fasting diets are emerging as an approach to delay tumor progression and improve cancer therapies. Here, the authors show that the combination of fasting-mimicking diet with vitamin C decreases tumor development and increases chemotherapy efficacy in KRAS-mutant cancer.

• Maira Di Tano
• Franca Raucci
• Valter D. Longo

Single-cell RNA sequencing demonstrates the molecular and cellular reprogramming of metastatic lung adenocarcinoma

Understanding the mechanisms that lead to lung adenocarcinoma metastasis is important for identifying new therapeutics. Here, the authors document the changes in the transcriptome of human lung adenocarcinoma using single-cell sequencing and link cancer cell signatures to immune cell dynamics.

• Nayoung Kim
• Hong Kwan Kim
• Hae-Ock Lee

A deep learning system accurately classifies primary and metastatic cancers using passenger mutation patterns

Some cancer patients first present with metastases where the location of the primary is unidentified; these are difficult to treat. In this study, using machine learning, the authors develop a method to determine the tissue of origin of a cancer based on whole sequencing data.

• Gurnit Atwal
• PCAWG Consortium

Single-cell RNA-sequencing of differentiating iPS cells reveals dynamic genetic effects on gene expression

Studying the genetic effects on early stages of human development is challenging due to a scarcity of biological material. Here, the authors utilise induced pluripotent stem cells from 125 donors to track gene expression changes and expression quantitative trait loci at single cell resolution during in vitro endoderm differentiation.

• Anna S. E. Cuomo
• Daniel D. Seaton
• Oliver Stegle

Trajectory-based differential expression analysis for single-cell sequencing data

Downstream of trajectory inference for cell lineages based on scRNA-seq data, differential expression analysis yields insight into biological processes. Here, Van den Berge et al. develop tradeSeq, a framework for the inference of within and between-lineage differential expression, based on negative binomial generalized additive models.

• Koen Van den Berge
• Hector Roux de Bézieux
• Lieven Clement

Large-scale genome-wide analysis links lactic acid bacteria from food with the gut microbiome

Here, Pasolli et al. perform a large-scale genome-wide comparative analysis of publicly available and newly sequenced food and human metagenomes to investigate the prevalence and diversity of lactic acid bacteria (LAB), indicating food as a major source of LAB species in the human gut.

• Edoardo Pasolli
• Francesca De Filippis
• Danilo Ercolini

Genetic history from the Middle Neolithic to present on the Mediterranean island of Sardinia

Ancient DNA analysis of early European farmers has found a high level of genetic affinity with present-day Sardinians. Here, the authors generate genome-wide capture data for 70 individuals from Sardinia spanning the Middle Neolithic to Medieval period to reveal relationships with mainland European populations shifting over time.

• Joseph H. Marcus
• Cosimo Posth
• John Novembre

Sex and APOE ε4 genotype modify the Alzheimer’s disease serum metabolome

Sex and the APOE ε4 genotype are important risk factors for late-onset Alzheimer’s disease. In the current study, the authors investigate how sex and APOE ε4 genotype modify the association between Alzheimer’s disease biomarkers and metabolites in serum.

• Matthias Arnold
• Kwangsik Nho
• Gabi Kastenmüller

Integrative pathway enrichment analysis of multivariate omics data

Multi-omics datasets pose major challenges to data interpretation and hypothesis generation owing to their high-dimensional molecular profiles. Here, the authors develop ActivePathways method, which uses data fusion techniques for integrative pathway analysis of multi-omics data and candidate gene discovery.

• Marta Paczkowska
• Jonathan Barenboim

Mitochondrial uncoupler BAM15 reverses diet-induced obesity and insulin resistance in mice

Obesity is a global pandemic with limited treatment options. Here, the authors show evidence in mice that the mitochondrial uncoupler BAM15 effectively induces fat loss without affecting food intake or compromising lean body mass.

• Stephanie J. Alexopoulos
• Sing-Young Chen
• Kyle L. Hoehn

Restriction of essential amino acids dictates the systemic metabolic response to dietary protein dilution

Dietary protein dilution, where protein is reduced and replaced by other nutrient sources without caloric restriction, promotes metabolic health via the hepatokine Fgf21. Here, the authors show that essential amino acids threonine and tryptophan are necessary and sufficient to induce these effects.

• Yann W. Yap
• Patricia M. Rusu
• Adam J. Rose

Multiplexed CRISPR technologies for gene editing and transcriptional regulation

Multiplexed CRISPR technologies have recently emerged as powerful approaches for genetic editing and transcriptional regulation. Here the authors review this emerging technology and discuss challenges and considerations for future studies.

• Nicholas S. McCarty
• Alicia E. Graham
• Rodrigo Ledesma-Amaro

Determining sequencing depth in a single-cell RNA-seq experiment

For single-cell RNA-seq experiments the sequencing budget is limited, and how it should be optimally allocated to maximize information is not clear. Here the authors develop a mathematical framework to show that, for estimating many gene properties, the optimal allocation is to sequence at the depth of one read per cell per gene.

• Martin Jinye Zhang
• Vasilis Ntranos

Sphingolipids produced by gut bacteria enter host metabolic pathways impacting ceramide levels

Ceramides are a type of sphingolipid (SL) that have been shown to play a role in several metabolic disorders. Here, the authors investigate the effect of SL-production by gut Bacteroides on host SL homeostasis and show that microbiome-derived SLs enter host circulation and alter ceramide production.

• Elizabeth L. Johnson
• Stacey L. Heaver
• Ruth E. Ley

Ancient genomes reveal social and genetic structure of Late Neolithic Switzerland

European populations underwent strong genetic changes during the Neolithic. Here, Furtwängler et al. provide ancient nuclear and mitochondrial genomic data from the region of Switzerland during the end of the Neolithic and the Early Bronze Age that reveal a complex genetic turnover during the arrival of steppe ancestry.

• Anja Furtwängler
• A. B. Rohrlach
• Johannes Krause

Brain insulin sensitivity is linked to adiposity and body fat distribution

Brain insulin action regulates eating behavior and whole-body energy fluxes, however the impact of brain insulin resistance on long-term weight and body fat composition is unknown. Here, the authors show that high brain insulin sensitivity is linked to weight loss during lifestyle intervention and associates with a favorable body fat distribution.

• Stephanie Kullmann
• Vera Valenta
• Martin Heni

Macrophages directly contribute collagen to scar formation during zebrafish heart regeneration and mouse heart repair

Macrophages mediate the fibrotic response after a heart attack by extracellular matrix turnover and cardiac fibroblasts activation. Here the authors identify an evolutionarily-conserved function of macrophages that contributes directly to the forming post-injury scar through cell-autonomous deposition of collagen.

• Filipa C. Simões
• Thomas J. Cahill
• Paul R. Riley

Sexual-dimorphism in human immune system aging

Whether the immune system aging differs between men and women is barely known. Here the authors characterize gene expression, chromatin state and immune subset composition in the blood of healthy humans 22 to 93 years of age, uncovering shared as well as sex-unique alterations, and create a web resource to interactively explore the data.

• Eladio J. Márquez
• Cheng-han Chung

Collagen-producing lung cell atlas identifies multiple subsets with distinct localization and relevance to fibrosis

Collagen production by lung cells is critical to maintain organ architecture but can also drive pathological scarring. Here the authors perform single cell RNA sequencing of collagen-producing lung cells identifying a subset of pathologic fibroblasts characterized by Cthrc1 expression which are concentrated within fibroblastic foci in fibrotic lungs and show a pro-fibrotic phenotype.

• Tatsuya Tsukui
• Kai-Hui Sun
• Dean Sheppard

Pathway and network analysis of more than 2500 whole cancer genomes

Understanding deregulation of biological pathways in cancer can provide insight into disease etiology and potential therapies. Here, as part of the PanCancer Analysis of Whole Genomes (PCAWG) consortium, the authors present pathway and network analysis of 2583 whole cancer genomes from 27 tumour types.

• Matthew A. Reyna

Single-cell transcriptomics identifies an effectorness gradient shaping the response of CD4 + T cells to cytokines

Cytokines critically control the differentiation and functions of activated naïve and memory T cells. Here the authors show, using multi-omics and single-cell analyses, that naïve and memory T cells exhibit distinct cytokine responses, in which an ‘effectorness gradient’ is depicted by a transcriptional continuum, which shapes the downstream genetic programs.

• Eddie Cano-Gamez
• Blagoje Soskic
• Gosia Trynka

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What is biology?

Biology is a branch of science that deals with living organisms and their vital processes. Biology encompasses diverse fields, including botany , conservation , ecology , evolution , genetics , marine biology , medicine , microbiology , molecular biology , physiology , and zoology .

As a field of science , biology helps us understand the living world and the ways its many species (including humans ) function, evolve, and interact. Advances in medicine , agriculture , biotechnology , and many other areas of biology have brought improvements in the quality of life. Fields such as genetics and evolution give insight into the past and can help shape the future, and research in ecology and conservation inform how we can protect this planet’s precious biodiversity .

Where do biology graduates work?

Biology graduates can hold a wide range of jobs, some of which may require additional education. A person with a degree in biology could work in agriculture , health care, biotechnology , education, environmental conservation, research, forensic science , policy, science communication, and many other areas.

biology , study of living things and their vital processes. The field deals with all the physicochemical aspects of life . The modern tendency toward cross-disciplinary research and the unification of scientific knowledge and investigation from different fields has resulted in significant overlap of the field of biology with other scientific disciplines . Modern principles of other fields— chemistry , medicine , and physics , for example—are integrated with those of biology in areas such as biochemistry , biomedicine, and biophysics .

Biology is subdivided into separate branches for convenience of study, though all the subdivisions are interrelated by basic principles. Thus, while it is custom to separate the study of plants ( botany ) from that of animals ( zoology ), and the study of the structure of organisms ( morphology ) from that of function ( physiology ), all living things share in common certain biological phenomena—for example, various means of reproduction , cell division , and the transmission of genetic material.

Biology is often approached on the basis of levels that deal with fundamental units of life. At the level of molecular biology , for example, life is regarded as a manifestation of chemical and energy transformations that occur among the many chemical constituents that compose an organism. As a result of the development of increasingly powerful and precise laboratory instruments and techniques, it is possible to understand and define with high precision and accuracy not only the ultimate physiochemical organization (ultrastructure) of the molecules in living matter but also the way living matter reproduces at the molecular level. Especially crucial to those advances was the rise of genomics in the late 20th and early 21st centuries.

Cell biology is the study of cells—the fundamental units of structure and function in living organisms. Cells were first observed in the 17th century, when the compound microscope was invented. Before that time, the individual organism was studied as a whole in a field known as organismic biology; that area of research remains an important component of the biological sciences. Population biology deals with groups or populations of organisms that inhabit a given area or region. Included at that level are studies of the roles that specific kinds of plants and animals play in the complex and self-perpetuating interrelationships that exist between the living and the nonliving world, as well as studies of the built-in controls that maintain those relationships naturally. Those broadly based levels— molecules , cells, whole organisms, and populations—may be further subdivided for study, giving rise to specializations such as morphology , taxonomy , biophysics, biochemistry, genetics , epigenetics , and ecology . A field of biology may be especially concerned with the investigation of one kind of living thing—for example, the study of birds in ornithology , the study of fishes in ichthyology , or the study of microorganisms in microbiology .

Basic concepts of biology

Biological principles.

The concept of homeostasis —that living things maintain a constant internal environment—was first suggested in the 19th century by French physiologist Claude Bernard , who stated that “all the vital mechanisms, varied as they are, have only one object: that of preserving constant the conditions of life.”

As originally conceived by Bernard, homeostasis applied to the struggle of a single organism to survive. The concept was later extended to include any biological system from the cell to the entire biosphere , all the areas of Earth inhabited by living things.

All living organisms, regardless of their uniqueness, have certain biological, chemical, and physical characteristics in common. All, for example, are composed of basic units known as cells and of the same chemical substances, which, when analyzed, exhibit noteworthy similarities, even in such disparate organisms as bacteria and humans . Furthermore, since the action of any organism is determined by the manner in which its cells interact and since all cells interact in much the same way, the basic functioning of all organisms is also similar.

There is not only unity of basic living substance and functioning but also unity of origin of all living things. According to a theory proposed in 1855 by German pathologist Rudolf Virchow , “all living cells arise from pre-existing living cells.” That theory appears to be true for all living things at the present time under existing environmental conditions. If, however, life originated on Earth more than once in the past, the fact that all organisms have a sameness of basic structure, composition , and function would seem to indicate that only one original type succeeded.

A common origin of life would explain why in humans or bacteria—and in all forms of life in between—the same chemical substance, deoxyribonucleic acid ( DNA ), in the form of genes accounts for the ability of all living matter to replicate itself exactly and to transmit genetic information from parent to offspring. Furthermore, the mechanisms for that transmittal follow a pattern that is the same in all organisms.

Whenever a change in a gene (a mutation ) occurs, there is a change of some kind in the organism that contains the gene. It is this universal phenomenon that gives rise to the differences ( variations ) in populations of organisms from which nature selects for survival those that are best able to cope with changing conditions in the environment .