Search bioRxiv⌕ Search

Biology subjects

Cheng, Y.

Publications and source records attributed to Cheng, Y..

At least 127 records · Page 7Linked to original sources

FishCODE: a web-based information platform for comprehensive omics data exploration in fish research

In terms of the utilization of omics data, the current fish database analysis functions are primarily relatively simple tools at the transcriptional level, aimed at obtaining the co-expression levels of specified genes or the data visualization of multiple genes, and do not enable users to perform comprehensive omics data analysis. Furthermore, the gene-level information currently provided by these multispecies fish genomics databases is incomplete, and there is a lack of a comprehensive portal that can offer multidimensional genetic information. To address these challenges, we collected extensive multi-omics information on 35 fishes and established the primary comprehensive multi-omics data information platform for fish, FishCODE (http://bioinfo.ihb.ac.cn/fishcode). We have collected experimental background of dataset which pertaining to the target fishes, selected a range of datasets that encompass a broad spectrum of research areas, and downloaded the corresponding raw omics data from public repositories such as the Sequence Read Archive (SRA). Through a unified pipeline analysis, FishCODE contains 11,216 samples from 540 sets of genomic, transcriptomic, and methylomic datasets. These data encompass transcript structure and expression, gene methylation levels, protein domains, protein subcellular localization, protein interactions, best matched protein (Swiss-Prot), associated SNP site information (47,111,018), orthologous genes, phylogenetic tree and GO/KEGG annotations. To facilitate comparison, we annotated the experimental background data sets of the FishCODE, FishGET, PhyloFish, FishSED and FishSCT databases using the Fish Experimental Condition Ontology. Currently, the FishCODE database omics dataset includes 146 unique experimental condition words, 654 cumulative experimental condition words, and 13 species with rich experimental background (more than 20 unique FECO words). These data are 3.5 times (42), 8.3 times (74), and 6.5 times (2) those of the second-ranked databases respectively. We generated word cloud maps for the experimental condition vocabularies of FishCODE and FishGET, illustrating the superior richness of FishCODEs experimental background.

bioinformatics↗

The HIV-1 Nuclear Export Complex Reveals the Role of RNA in Crm1 Cargo Recognition

Crm1 is a highly conserved nuclear exportin that transports >1000 human proteins including ribonucleoprotein (RNP) complexes. The interface between Crm1 and RNP cargos is unknown. The HIV regulatory protein, Rev, was one of the first identified cargos for Crm1 and contains a prototypic nuclear export sequence (NES). We present the cryo-electron microscopy structure of the HIV-1 nuclear export complex (Crm1/Ran-GTP and the Rev/RRE RNP). Rev binds at a previously unseen protein-protein binding site that stabilizes a unique Crm1 dimer and positions two NESs within the Crm1 dimer. The orientation of Rev binding positions the RRE within a charged pocket on the inside of the Crm1 toroid, mediating direct RNA-Ran-GTP contacts, highlighting the significant role of the RRE in the interaction. Structure based mutations, combined with cell-based assays, show that Crm1 has multiple distinct cargo recognition sites and explains how Crm1 can recognize a diverse range of protein and RNP cargos.

biochemistry↗

Listening to music modulates visual perception of paintings during binocular rivalry

Music, as a hierarchically organized art form, profoundly influences perception and mood through its rich information and intense emotion. While previous research has demonstrated that music can shape visual perception, its influences on visual awareness in aesthetic scenes remain largely unclear. In a series of five experiments involving 138 participants, we used the binocular rivalry paradigm to investigate how sad or lively Chinese folk music influences the perception of traditional Chinese paintings with varying aesthetic emotion (bleak vs. vivid). Paintings were presented in upright or inverted orientations or replaced by patches. Results revealed that sad music significantly increased both the average dominance duration and the predominance score of bleak paintings. Conversely, lively music with a faster tempo accelerated the switch rate of both paintings and patches. These effects were interdependent, exclusively for meaningful (upright) paintings, and correlated with individual sensitivity to musical reward. Our findings support the hierarchical predictive coding model of binocular rivalry, demonstrating that musical aesthetic emotion exerts top-down modulation, while musical tempo provides bottom-up entrainment, jointly shaping visual awareness of paintings.

systems biology↗

How environment and genetic architecture of unreduced gametes shape the establishment of autopolyploids

It is broadly assumed that polyploidy success is due to an increase in fitness associated with whole genome duplication due to higher tolerance to stressful conditions. In agreement, several theoretical models found that, among other factors, a better tolerance to new environmental conditions can promote polyploidy establishment. These models, however, often made strong hypotheses, for example considering that diploids cannot adapt to new conditions, or that unreduced gametes production is not a limiting factor and that it is of a fixed quantity. In this paper, we challenged some of these hypotheses. We developed a theoretical model in which we modeled the joint evolution of a quantitative trait under selection and the production of unreduced gametes, this trait also being a quantitative trait; both traits were pleiotropically linked. We followed the adaptation of initially diploid populations to a new environment to which neo-tetraploid individuals were directly adapted. The generation of these autotetraploid individuals was enabled by the genetic production of unreduced gametes and by the environmental change modifying the average production of these gametes. We found that for realistic values of unreduced gametes production, adaptation to new environmental conditions was mainly achieved through adaptation of diploids to the new optimum rather than the fixation of newly adapted tetraploid individuals. In broader parameter sets, we found that the adaptation process led to mixed-ploidy populations, except when the populations were swamped with unreduced gametes, and that pleiotropy and environmental effects favored the co-existence of both cytotypes.

evolutionary biology↗

HMGB1 restores a dynamic chromatin environment in the presence of linker histone by deforming nucleosomal DNA

The essential architectural protein HMGB1 increases accessibility of nucleosomal DNA and counteracts the effects of linker histone H1. However, HMGB1 is less abundant than H1 and binds nucleosomes more weakly raising the question of how HMGB1 effectively competes with H1. Here, we show that HMGB1 rescues H1s inhibition of nucleosomal DNA accessibility without displacing H1. HMGB1 also increases the dynamics of condensed, H1-bound chromatin. Cryo-EM shows that HMGB1 binds at internal locations on a nucleosome and locally distorts the DNA. These sites, which are away from the binding site of H1, explain how HMGB1 and H1 co-occupy a nucleosome. Our findings lead to a model where HMGB1 counteracts the activity of H1 by distorting nucleosomal DNA and by contacting the H1 C-terminal tail. Compared to direct competition, nucleosome co-occupancy by HMGB1 and H1 allows a greater diversity of dynamic chromatin states and may be generalizable to other chromatin regulators.

biochemistry↗

Shared and Unique Neural Codes for Biological Motion Perception in Humans and Macaque Monkeys

Throughout evolution, living organisms have honed the ability to swiftly recognize biological motion (BM) across species. However, how the brain processes within- and cross-species BM, and the evolutionary progression of these processes, remain unclear. To investigate these questions, we examined brain activity in the lateral temporal areas of humans and monkeys as they passively observed upright and inverted human and macaque BM stimuli. In humans, the middle temporal area (hMT+) responded to both human and macaque BM stimuli, while the right posterior superior temporal sulcus (pSTS) exhibited selective responses to human BM stimuli. This selectivity was evidenced by an increased feedforward connection from hMT+ to pSTS during the processing of human BM stimuli. In monkeys, the MT region processed BM stimuli from both species, but no subregion in the STS anterior to MT was specific to conspecific BM stimuli. A comparison of these findings suggests that upstream brain regions (i.e., MT) may retain homologous functions across species, while downstream brain regions (i.e., STS) may have undergone differentiation and specialization throughout evolution. These results provide insights into the commonalities and differences in the specialized visual pathway engaged in processing within- and cross-species BMs, as well as their functional divergence during evolution.

neuroscience↗

Mixed outcomes in recombination rates after domestication: Revisiting theory and data

The process of domestication has altered many phenotypes. Selection on these phenotypes has long been hypothesized to indirectly select for increases in recombination rate. This hypothesis is consistent with theory on the evolution of recombination rate, but empirical support has been unclear. We review relevant theory, lab-based experiments, and data comparing recombination rates in wild progenitors and their domesticated counterparts. We utilize population sequencing data and a deep learning method to infer genome-wide recombination rates for new comparisons of chicken/red junglefowl, sheep/mouflon, and goat/bezoar. We find evidence of increased recombination in domestic goats compared to bezoars, but more mixed results in chicken, and generally decreased recombination in domesticated sheep compared to mouflon. Our results add to a growing body of literature in plants and animals that finds no consistent evidence of an increase in recombination with domestication.

evolutionary biology↗

Brain-Engrafted Monocyte-derived Macrophages from Blood and Skull-Bone Marrow Exhibit Distinct Identities from Microglia

Microglia are thought to originate exclusively from primitive macrophage progenitors in the yolk sac (YS) and to persist throughout life without much contribution from definitive hematopoiesis. Here, using lineage tracing, pharmacological manipulation, and RNA-sequencing, we elucidated the presence and characteristics of monocyte-derived macrophages (MDMs) in the brain parenchyma at baseline and during microglia repopulation, and defined the core transcriptional signatures of brain-engrafted MDMs. Lineage tracing mouse models revealed that MDMs transiently express CD206 during brain engraftment as CD206+ microglia precursors in the YS. We found that brain-engrafted MDMs exhibit transcriptional and epigenetic characteristics akin to meningeal macrophages, likely due to environmental imprinting within the meningeal space. Utilizing parabiosis and skull transplantation, we demonstrated that monocytes from both peripheral blood and skull bone marrow can repopulate microglia-depleted brains. Our results reveal the heterogeneous origins and cellular dynamics of brain parenchymal macrophages at baseline and in models of microglia depletion.

immunology↗

An updated and expanded characterization of the biological sciences academic job market

In the biological sciences, many areas of uncertainty exist regarding the factors that contribute to success within the faculty job market. Earlier work from our group reported that beyond certain thresholds, academic and career metrics like the number of publications, fellowships or career transition awards, and years of experience did not separate applicants who received job offers from those who did not. Questions still exist regarding how academic and professional achievements influence job offers and if candidate demographics differentially influence outcomes. To continue addressing these gaps, we initiated surveys collecting data from faculty applicants in the biological sciences field for three hiring cycles in North America (Fall 2019 to the end of May 2022), a total of 449 respondents were included in our analysis. These responses highlight the interplay between various scholarly metrics, extensive demographic information, and hiring outcomes, and for the first time, allowed us to look at persons historically excluded due to ethnicity or race (PEER) status in the context of the faculty job market. Between 2019 and 2022, we found that the number of applications submitted, position seniority, and identifying as a women or transgender were positively correlated with a faculty job offer. Applicant age, residence, first generation status, and number of postdocs, however, were negatively correlated with receiving a faculty job offer. Our data are consistent with other surveys that also highlight the influence of achievements and other factors in hiring processes. Providing baseline comparative data for job seekers can support their informed decision-making in the market and is a first step towards demystifying the faculty job market.

scientific communication and education↗

An ultraconserved snoRNA-like element in long noncoding RNA CRNDE promotes ribosome biogenesis and cell proliferation

Cancer cells frequently upregulate ribosome production to support tumorigenesis. While small nucleolar RNAs (snoRNAs) are critical for ribosome biogenesis, the roles of other classes of noncoding RNAs in this process remain largely unknown. Here we performed CRISPRi screens to identify essential long noncoding RNAs (lncRNAs) in renal cell carcinoma (RCC) cells. This revealed that an alternatively-spliced isoform of lncRNA Colorectal Neoplasia Differentially Expressed containing an ultraconserved element (UCE), referred to as CRNDEUCE, is required for RCC cell proliferation. CRNDEUCE localizes to the nucleolus and promotes 60S ribosomal subunit biogenesis. The UCE of CRNDE functions as an unprocessed C/D box snoRNA that directly interacts with ribosomal RNA precursors. This facilitates delivery of eIF6, a key 60S biogenesis factor, which binds to CRNDEUCE through a sequence element adjacent to the UCE. These findings highlight the functional versatility of snoRNA sequences and expand the known mechanisms through which noncoding RNAs orchestrate ribosome biogenesis.

molecular biology↗

Upregulation of a nonsense mediated decay (NMD) insensitive CFTR mRNA isoform has therapeutic potential for the treatment of 3 Prime CFTR PTC variants

BackgroundNonsense or Premature Termination Codon (PTC) mutations of the CFTR gene are pathogenic and found in [~]10% of North American people with cystic fibrosis. PTC mutations induce Nonsense-Mediated mRNA Decay (NMD), leading to a substantial ([~]80-90%) reduction in full-length mRNA. This reduction is a key contributor to PTC mutation-related pathology. Various approaches to evade NMD and preserve the impacted mRNA transcript have been explored but have not progressed to clinical development, leaving NMD a significant hurdle for PTC readthrough therapy. MethodsAntisense oligonucleotides (ASOs) were tiled across intron 22 splice donor (SD) and acceptor (SA) sites of the CFTR gene. Immortalized airway cells were treated with SD and SA ASOs, and those yielding the greatest increase in a CFTR NMD-insensitive mRNA isoform (e22 trunc mRNA) were tested in combinations. Top SD/SA ASO pairs were assessed for their impact on e22 trunc mRNA via ddPCR, e22 trunc protein via western blot, and CFTR-mediated chloride (Cl-) transport via transepithelial electrophysiological measurements in immortalized and primary human bronchial epithelial (hBE) cell cultures. ResultsWe demonstrate that e22 trunc mRNA generates a truncated CFTR protein whose Cl- transport function can be enhanced with elexacaftor/tezacaftor/ivacaftor (ETI) treatment. ASO and ETI treatment in combination restore [~]20% and 25% of wild-type CFTR Cl- transport function in immortalized epithelial and primary hBE cells homozygous for CFTR W1282X, respectively. ConclusionsThis study lays the groundwork for advancing ASO-mediated upregulation of e22 trunc mRNA and protein as a therapeutic approach for cystic fibrosis caused by 3-terminal CFTR PTC mutations.

genomics↗

Deficiency of m6A RNA methylation promotes ZBP1-mediated cell death

m6A RNA methylation suppresses the immunostimulatory potential of endogenous RNA. Deficiency of m6A provokes inflammatory responses and cell death, but the underlying mechanisms remain elusive. Here we showed that the noncoding RNA 7SK gains immunostimulatory potential upon m6A depletion and subsequently activates the RIG-I/MAVS axis to spark interferon (IFN) signaling cascades. Concomitant excess of IFN and m6A deficiency synergistically facilitate the formation of RNA G-quadruplexes (rG4) to promote ZBP1-mediated necroptotic cell death. Collectively, our findings delineate a hitherto uncharacterized mechanism that links m6A dysregulation with ZBP1 activity in triggering inflammatory cell death.

molecular biology↗

Neuropathologically-directed profiling of PRNP somatic and germline variants in sporadic human prion disease

Creutzfeldt-Jakob Disease (CJD), the most common human prion disease, is associated with pathologic misfolding of the prion protein (PrP), encoded by the PRNP gene. Of human prion disease cases, [~]1% were transmitted by misfolded PrP, [~]15% are inherited, and [~]85% are sporadic (sCJD). While familial cases are inherited through germline mutations in PRNP, the cause of sCJD is unknown. Somatic mutations have been hypothesized as a cause of sCJD, and recent studies have revealed that somatic mutations accumulate in neurons during aging. To investigate the hypothesis that somatic mutations in PRNP may underlie sCJD, we performed deep DNA sequencing of PRNP in 205 sCJD cases and 170 age-matched non-disease controls. We included 5 cases of Heidenhain variant sporadic CJD (H-sCJD), where visual symptomatology and neuropathology implicate focal initiation of prion formation, and examined multiple regions across the brain including in the affected occipital cortex. We employed Multiple Independent Primer PCR Sequencing (MIPP-Seq) with a median depth of >5,000X across the PRNP coding region and analyzed for variants using MosaicHunter. An allele mixing experiment showed positive detection of variants in bulk DNA at a variant allele fraction (VAF) as low as 0.2%. We observed multiple polymorphic germline variants among individuals in our cohort. However, we did not identify bona fide somatic variants in sCJD, including across multiple affected regions in H-sCJD, nor in control individuals. Beyond our stringent variant-identification pipeline, we also analyzed VAFs from raw sequencing data, and observed no evidence of prion disease enrichment for the known germline pathogenic variants P102L, D178N, and E200K. The lack of PRNP pathogenic somatic mutations in H-sCJD or the broader cohort of sCJD suggests that clonal somatic mutations may not play a major role in sporadic prion disease. With H-sCJD representing a focal presentation of neurodegeneration, this serves as a test of the potential role of clonal somatic mutations in genes known to cause familial neurodegeneration.

genetics↗

Human cancer genomes harbor the mutational signature of tobacco-specific nitrosamines NNN and NNK

Tobacco usage is linked to multiple cancer types and accounts for a quarter of all cancer-related deaths. Tobacco smoke contains various carcinogenic compounds, including polycyclic aromatic hydrocarbons (PAH), though the mutagenic potential of many tobacco-related chemicals remains largely unexplored. In particular, the highly carcinogenic tobacco-specific nitrosamines NNN and NNK form pre-mutagenic pyridyloxobutyl (POB) DNA adducts. In the study presented here, we identified genome-scale POB-induced mutational signatures in cell lines and rat tumors, while also investigating their role in human cancer. These signatures are characterized by T>N and C>T mutations forming from specific POB adducts damaging dT and dC residues. Analysis of 2,780 cancer genomes uncovered POB signatures in [~]180 tumors; from cancer types distinct from the ones linked to smoking-related signatures SBS4 and SBS92. This suggests that, unlike PAH compounds, the POB pathway may contribute uniquely to the mutational landscapes of certain hematological malignancies and cancers of the kidney, breast, prostate and pancreas.

genomics↗

Nonlinear compliance of NompC gating spring and its implication in mechanotransduction

Cytoskeleton-tethered mechanosensitive channels (MSCs) utilize compliant proteins or protein domains called gating springs to convert mechanical stimuli into electric signals, enabling sound and touch sensation and proprioception. The mechanical properties of these gating springs, however, remain elusive. Here, we explored the mechanical properties of the homotetrameric NompC complex containing long ankyrin-repeat domains (ARDs). We developed a toehold-mediated strand displacement approach to tether single membrane proteins, allowing us to exert force on them and precisely measure their absolute extension using optical tweezers. Our findings revealed that each ARD has a low stiffness of [~]0.7 pN/nm and begins to unfold stepwise at [~]7 pN, leading to nonlinear compliance. Our calculations indicate that this nonlinear compliance may help regulate NompCs sensitivity, dynamic range, and kinetics to detect mechanical stimuli. Overall, our research highlights the importance of a compliant and unfolding-refolding gating spring in facilitating a graded response of MSC ion transduction across a wide spectrum of mechanical stimuli.

biophysics↗

Structure of the E3 ligase CRL2-ZYG11B with substrates reveals the molecular basis for N-degron recognition and ubiquitination

ZYG11B is a substrate specificity factor for Cullin-RING ubiquitin ligase (CRL2) involved in many biological processes, including Gly/N-degron pathways. Yet how the binding of ZYG11B with CRL2 is coupled to substrate recognition and ubiquitination is unknown. We present the Cryo-EM structures of the CRL2-ZYG11B holoenzyme alone and in complex with a Gly/N-peptide from the inflammasome-forming pathogen sensor NLRP1. The structures indicate ZYG11B folds into a Leucine-Rich Repeat followed by two armadillo repeat domains that promote assembly with CRL2 and recognition of NLRP1 Gly/N-degron. ZYG11B promotes activation of the NLRP1 inflammasome through recognition and subsequent ubiquitination of the NLRP1 Gly/N-degron revealed by viral protease cleavage. Our structural and functional data indicate that blocking ZYG11B recognition of the NLRP1 Gly/N-degron inhibits NLRP1 inflammasome activation by a viral protease. Overall, we show how the CRL2-ZYG11B E3 ligase complex recognizes Gly/N-degron substrates, including those that are involved in viral protease-mediated activation of the NLRP1 inflammasome.

molecular biology↗

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

BackgroundInfertility 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 that serves as an endocrine signal between adiposity and fertility. However, the exact mechanisms underlying the effects of high leptin on female reproduction remain unclear. MethodsTransgenic pig overexpressing leptin (11) were produced by back cross and screened for leptin overexpression, and the growth curve, fat deposition, reproductive performance, apoptosis, serum hormones and cholesterol production, RNA sequencing, and single nucleus RNA sequencing of the leptin-overexpressed pigs and control group were evaluated. ResultsTransgenic pig overexpressing leptin (11) were obtained, which exhibited significantly reduced body weight, body size, and back fat thickness. These pigs manifested late onset of puberty (327{+/-}48.5 vs 150{+/-}6.5 days), irregular estrous behavior characterized by increased inter-estrous interval (28.1{+/-}4.2 vs 21.3 {+/-} 0.9 days), and more numbers of mating until pregnancy (at least 3 times). This reproductive impairment in leptin pigs was related to hormonal imbalances characterized by increased levels of FSH, LH, prolactin, E2, P4, and TSH, altered steroidogenesis such as increased levels of serum CE along with steroidogenic markers (STAR, CYP19A), and ovarian dysfunctions manifested by neutrophilic infiltration and low expression of caspase-3 positive cells on leptin pigs ovary. Meanwhile, bulk RNA sequencing of the ovaries also revealed neutrophilic infiltration followed by upregulation of inflammation-related genes. Further, leptin overexpression triggered immune response, suppressed follicle development and luteinization, imposing metabolism dysfunction and hormone imbalance in the ovary by single-nucleus RNA sequencing (snRNA-seq). ConclusionLow body weight in leptin overexpression pigs adversely affects reproductive performance, causing delayed puberty, irregular estrous cycles, and reduced breeding efficiency. This is linked to metabolic imbalances, increased immune response, and altered ovarian functions. This study provided a theoretical basis for the complex mechanisms underlying leptin, and infertility by employing leptin-overexpressed female pigs.

genetics↗

Clonal expansion dictates the efficacy of mitochondrial lineage tracing in single cells

Although mitochondrial DNA (mtDNA) variants hold promise as endogenous barcodes for tracking human cell lineages, their efficacy as reliable lineage markers is hindered by the complex dynamics of mtDNA in somatic tissues. Here, we utilized computational modeling and single-cell genomics to thoroughly interrogate the origin and clonal dynamics of mtDNA lineage markers across various biological settings. Our findings revealed the majority of purported "clone informative variants (CIVs)" were pre-existing heteroplamies in the first cell instead of de novo somatic mutations during divisions. Moreover, CIVs demonstrated limited discriminatory power among different lineages during normal development; however, certain CIVs with consistently high allele frequencies proved capable of faithfully labeling cell lineages in scenarios of stringent clonal expansion. Inspired by our simulations, we introduced a lineage informative (LI) score, facilitating the identification of reliable mitochondrial lineage markers across different modalities of single-cell genomic data.

bioinformatics↗