bioRxiv Science⌕ Search

Biology subjects

Lin, F.

Publications and source records attributed to Lin, F..

At least 55 records · Page 3Linked to original sources

Chromosome-level de novo genome unveils the evolution of Gleditsia sinensis and thorns development

Gleditsia Linn is widely distributed in the world and Gleditsia sinensis as an important Leguminosae specie, especially its thorns, has been used in the Chinese medicine as a chief ingredient for centuries. While the lack of genome database limits its in-depth research, especially genetic regulation and molecular developmental mechanism. In this investigation, a chromosome-level de novo genome of G. sinensis was assembled through PacBio HiFi, Illumina sequencing as well as those from Hi-C, genetic mapping and K-mer analysis. The G. sinensis harbors 786.13 Mb sized genome (contig N50=1.58 Mb, scaffold N50=51.53 Mb, 2n=28) with 36, 408 protein-coding genes. The full-length transcriptome sequencing of diverse tissues was performed to assist genome functional annotation. The comparative and evolutionary analysis unveiled that G. sinensis diverged from the Cretaceous period approximately 76.31 million years ago (Mya) and the close relationship between G. sinensis and other 8 Leguminosae species. The whole-genome duplication (WGD) analysis indicated G. sinensis underwent three WGD events and might go through another WGD event after differentiating from other Leguminosae plants. The Weighted Gene Coexpression Network Analysis based on phenotype and differentially expressed genes further demonstrated that GsinMYB should be involved in the development of thorns via regulating late thorn differentiation. This investigation provides a high level genome of Gleditsia for Leguminosae species evolution comparison and functional elucidation and also key insights for further study on the molecular regulation mechanisms of the thorns development as a special abnormal stem organ in plants and the molecular breeding of G. sinensis.

genomics↗

Castration Model Illuminates Sex Differences in Healthy Aging: Insights from Metabolome and Transcriptome Analyses

BackgroundSex, as a critical biological variable, has historically been underappreciated, despite the pervasive influence of sexual dimorphism across physiological and pathological processes. A significant obstacle to advancing sex-biased biological research is the absence of an effective animal model. In recent years, castration has emerged as a potential model for elucidating sex-based differences in the context of healthy aging, where it has been shown to equalize lifespan and growth trajectories in genetically diverse mice. However, the molecular shifts induced by castration in common laboratory models, such as C57BL/6 mice, and the broader applicability of this model to other sex-related biological contexts remain largely unexplored. MethodsWe employed multi-omics and observational analyses to investigate the molecular changes associated with sex and sex hormones following castration. We analyzed serum, kidney, and liver samples from 12-week-old and 18-month-old castrated male C57BL/6 mice, alongside intact male and female counterparts. The castration model was further applied to assess differences in cisplatin-induced toxicity and age-related cognitive decline in comparison to unaltered controls. ResultsLC-MS/MS metabolomics revealed that castrated males exhibited substantial alterations in steroid hormone levels and increased concentrations of antioxidant compounds, such as taurine, despite identical diets. Integrated metabolome-transcriptome analysis confirmed distinct patterns of lipid peroxidation and oxidative stress across sham-operated female, male, and castrated male mice. Histopathological evaluations following cisplatin treatment and aging-related behavioral tests demonstrated the models utility in investigating sex-dependent drug toxicity and cognitive decline. These findings underscored the critical role of sex hormones in modulating both toxicity defense mechanisms and cognitive performance. ConclusionThis study provides a systematic multi-omics spectrum on the castration model and demonstrates its capacity to feminize metabolic and transcriptomic profiles, establishing it as a valuable tool for exploring sex hormone-driven biological differences. Our findings lay the groundwork for further mechanistic studies and broaden the potential applications of the castration model in diverse biomedical research domains.

systems biology↗

Structural basis of nucleosomal H4K20 recognition and methylation by SUV420H1 methyltransferase

Histone lysine methyltransferase of SUV420H1, which is responsible for site-specific di-/tri-methylation of histone H4 lysine 20 (H4K20), has crucial roles in DNA-templated processes, including DNA replication, DNA damage repair and chromatin compaction. Its mutations frequently occur in human cancers. Nucleosomes containing the histone variant H2A.Z enhance the catalytic activities of SUV420H1 in H4K20 di-methylation deposition, regulating early replication origins. However, the molecular mechanism of how H4K20 methyl marks are deposited on nucleosomes by SUV420H1 remains poorly understood. Here we report the cryo-electron microscopy (cryo-EM) structures of SUV420H1 associated with canonical nucleosome core particles (NCPs) or H2AZ containing NCPs. We find that SUV420H1 make extensive site-specific contacts with histone and DNA regions. SUV420H1 C-terminal domain recognizes the H2A-H2B acidic pocket of NCPs through its two arginine anchors, thus enabling H4K20 insertion for catalysis specifically. We also identify important residues increasing the catalytic activities of SUV420H1 bound to H2A.Z NCPs. In vitro and in vivo functional analysis reveal that multiple disease associated mutations at the interfaces are essential for its catalytic activity and chromatin states regulation. Together, our study provides molecular insights into the nucleosome-based recognition and methylation mechanisms of SUV420H1, and a structural basis for understanding SUV420H1-related human disease.

molecular biology↗

Identification of B56alpha, B56gamma; and BAP1 as PRR14L binding partners

Truncating mutations have been previously described in PRR14L associated with acquired isodisomy of chromosome 22 in myeloid neoplasms. Very little is known about the function of PRR14L, but previous work showed localization to the midbody and binding to KIF4A. Here we confirm binding of PRR14L to PP2A components B56 and B56{gamma}. Similar to the related protein PRR14, PRR14L binds B56 via a conserved short linear motif within the C-terminal Tantalus domain. We also confirmed binding to BAP1, which forms the H2A deubiquinating complex PR-DUB with ASXL1, thereby linking PRR14L to a protein with established leukemogenic significance. AlphaFold data predicts PRR14L structure to be largely disordered, consistent with a possible role as a scaffold protein.

cancer biology↗

Lepidoptera proboscis pollens are mainly derived from nectar

The pollens which are rejected or ignored by the dry stigma cant germinate since they havent acquired sugar solution from dry stigmas. But almost all research has ignored the participation of insects which may transport pollens from the nectar to stigmas, and that pollens may germinate on the dry stigma since they have soaked in the nectar. So, the key question is that whether insects carry pollens from nectar to the stigma. Since the adult Lepidoptera are important to the plant pollination and there is a general consensus that pollens are mainly deposited on the proboscis of adult Lepidoptera, and pollens are ubiquitous in the nectar of field flowers, we simulated the flower environment to conduct several groups of behavioral experiments in the adult Mythimna separata by controlling the presence, absence or movement of pollens in nectar, then counted and compared the proboscis pollens. We found that the pollens on the proboscis were mainly derived from the nectar. Our conclusion may contributes to the research of pollen germination on stigmas, especially the dry stigma, and also shows the importance of adult Lepidoptera to pollination, even supports the coevolution of Lepidoptera and angiosperm.

zoology↗

Hepatic conversion of acetyl-CoA to acetate plays crucial roles in energy stresses

Accumulating evidences indicate that acetate is increased in energy stresses such as diabetes mellitus and prolonged starvation. However, it is largely unknown how and where acetate is produced and what is its biological significance. We observed overproduction of acetate in an amount comparable to ketone bodies in patients and mice with diabetes or starvation. Mechanistically, ACOT 12&8 are dramatically upregulated in liver to convert FFA-derived acetyl-CoA to acetate and CoA. This conversion not only provides large amount of acetate which fuels brain preferentially rather than muscle, but also recycles CoA which is required for sustained fatty acid oxidation and ketogenesis. Taken together, we suggest that acetate is an emerging novel "ketone body" and may be used as a parameter to evaluate the progression of energy stress in the future.

biochemistry↗

Pathogen and human NDPK-proteins promote AML cell survival via monocyte NLRP3-inflammasome activation.

A history of infection has been linked with increased risk of acute myeloid leukaemia (AML) and related myelodysplastic syndromes (MDS). Furthermore, AML and MDS patients suffer frequent infections because of disease-related impaired immunity. However, the role of infections in the development and progression of AML and MDS remains poorly understood. We and others previously demonstrated that the human nucleoside diphosphate kinase (NDPK) NM23-H1 protein promotes AML blast cell survival by inducing secretion of IL-1{beta} from accessory cells. NDPKs are an evolutionary highly conserved protein family and pathogenic bacteria secrete NDPKs that regulate virulence and host-pathogen interactions. Here, we demonstrate the presence of IgM antibodies against a broad range of pathogen NDPKs and more selective IgG antibody activity against pathogen NDPKs in the blood of AML patients and normal donors, demonstrating that in vivo exposure to NDPKs likely occurs. We also show that pathogen derived NDPK-proteins faithfully mimic the catalytically independent pro-survival activity of NM23-H1 against primary AML cells. Flow cytometry identified that pathogen and human NDPKs selectively bind to monocytes in peripheral blood. We therefore used vitamin D3 differentiated monocytes from wild type and genetically modified THP1 cells as a model to demonstrate that NDPK-mediated IL-1{beta} secretion by monocytes is NLRP3-inflammasome and caspase 1 dependent, but independent of TLR4 signaling. Monocyte stimulation by NDPKs also resulted in activation of NF-{kappa}B and IRF pathways but did not include the formation of pyroptosomes or result in pyroptotic cell death which are pivotal features of canonical NLRP3 inflammasome activation. In the context of the growing importance of the NLRP3 inflammasome and IL-1{beta} in AML and MDS, our findings now implicate pathogen NDPKs in the pathogenesis of these diseases. Author SummaryAcute myeloid leukaemia (AML) and myelodysplastic syndromes MDS) are related blood cancers that are associated with frequent infections because the cancers suppress normal immunity. These infections are therefore generally considered as medical complications arising as a result of but separate to the cancer. However, we provide evidence here that infections may promote or drive cancer progression. We and others previously demonstrated that a human protein called NM23-H1 promotes the survival of AML cells by eliciting survival signals from other cells. NM23-H1 belongs to a highly conserved family of proteins that also occur in bacteria and fungi that cause infections in AML and MDS patients. Here we demonstrate that these bacterial and fungal proteins recapitulate the pro-survival effect of NM23-H1 on AML cells. We also determine that these effects are mediated via mechanisms already known to be important in the development and progression of AML and MDS. This study is the first to identify NM23-H1 like proteins from pathogenic microorganisms as novel activators of these pathways. These findings have important implications for how we understand infections in AML and MDS patients and suggest that in addition to being the consequence of these diseases, infections may also drive the cancer process.

microbiology↗

An international scholastic network to generate LexA enhancer-trap lines for Drosophila

Conditional gene regulation in Drosophila through binary expression systems like the LexA-LexAop system provides a superb tool for investigating gene and tissue function. To increase the availability of defined LexA enhancer trap insertions, we present molecular, genetic and tissue expression studies of 301 novel Stan-X LexA enhancer traps derived from mobilization of the index SX4 line. This includes insertions into distinct loci on the X, II and III chromosomes that were not previously associated with enhancer traps or targeted LexA constructs, an insertion into ptc, and eleven insertions into natural transposons. A subset of enhancer traps was expressed in CNS neurons known to produce and secrete insulin, an essential regulator of growth, development and metabolism. Fly lines described here were generated and characterized through studies by students and teachers in an international network of genetics classes at public, independent high schools, and universities serving a diversity of students, including those underrepresented in science. Thus, a unique partnership between secondary schools and university-based programs has produced and characterized novel resources in Drosophila, establishing instructional paradigms devoted to unscripted experimental science.

genetics↗

Robust identification of extrachromosomal DNA and genetic variants using multiple genetic abnormality sequencing (MGA-Seq)

Genomic abnormalities, including structural variation (SV), copy number variation (CNV), single-nucleotide polymorphism (SNP), homogenously staining regions (HSR) and extrachromosomal DNA (ecDNA), are strongly associated with cancer, rare diseases and infertility. A robust technology to simultaneously detect these genomic abnormalities is highly desired for clinical diagnosis and basic research. In this study, we developed a simple and cost-effective method - multiple genetic abnormality sequencing (MGA-Seq) - to simultaneously detect SNPs, CNVs, SVs, ecDNA and HSRs in a single tube. This method has been successfully applied in both cancer cell lines and clinical tumour samples and revealed that focal amplification in tumour tissue is substantially heterogeneous. Notably, we delineated the architecture of focal amplification and the ecDNA network by MGA-Seq, which facilitated the exploration of the regulation of gene expression in ecDNA. This method could be extensively applied for diagnosis and may greatly facilitate the investigation of the genomic mechanism for genetic diseases.

genomics↗

A new LD protein, ApoL6 disrupts the Perilipin 1-HSL interaction to inhibit lipolysis

ApoL6 is a new LD-associated protein containing an apoprotein-like domain, expressed mainly in adipose tissue, specifically in adipocytes. ApoL6 expression is low in fasting but induced upon feeding. ApoL6 knockdown results in smaller LD with lower triglyceride (TAG) content in adipocytes, while ApoL6 overexpression causes larger LD with higher TAG content. We show that ApoL6 effect in adipocytes is by inhibition of lipolysis. While ApoL6, Perilipin 1 (Plin1) and HSL can form a complex on LD, C-terminal domain of ApoL6 directly interacts with Plin1, to compete with Plin1 binding to HSL through Plin1 N-terminal domain, thereby keeping HSL in a "stand by" status. Thus, ApoL6 ablation decreases WAT mass, protecting mice from diet-induced obesity, while adipose overexpression increases WAT mass to bring obesity and insulin resistance with hepatosteatosis, making ApoL6 a potential future target against obesity and diabetes.

molecular biology↗

Disruption of OsLAT5 is sufficient to endow rice tolerance to dihydropyridine herbicides at commercial application concentrations

Breeding non-selective herbicide-resistant crops is important constituent of weed management system in modern rice production. Non-selective dihydropyridine herbicide shares transporters with polyamine (PA), making construction of a dihydropyridine herbicide-resistant rice line possible by inactivating the PA transporter function via gene editing. Success depends on understanding substrate selection for homologues in the PA transporter family and amino acid sites that play critical roles. Here, OsLAT1 was mainly responsible for root uptake and root-to-shoot transport; whereas, OsLAT5 was more responsible for intracellular transport to chloroplasts. The oslat5 disruption line tolerated relevant concentrations, while oslat1 did not. Compared to GY11 wild type, plant height, 1000-grain weight, and spermidine, spermine, and putrescine content changes occurred in GY11-oslat5 lines, implying involvement of OsLAT5 in yield and quality regulation. OsLAT5P44F, P44Y and P44R showed declined dihydropyridine herbicide uptake but no spermidine and putrescine transport competence disruption in yeast, providing a candidate site for precisely editing in breeding a dihydropyridine herbicide-resistant rice cultivar without impairing rice yield and grain quality.

plant biology↗

Oral Feeding of Nanoplastics reduces Brain function of Mice by Inducing Intestinal IL-1β-producing Macrophages

Background and AimsNanoplastics (NPs) as contaminants in food and water have drawn an increasing public attention. However, little is known about how NPs shape the gut immune landscape after entering the body. The objective of the study was to explore indirect effects caused by the interaction of NPs with the mammalian gut and whole immune system after entering the body. MethodsIn this study, we fabricated NPs ([~]500 nm) and microplastics (MPs) ([~]2 m) and aimed to evaluate their in vivo effects by feeding them in mice. The mechanism was then investigated by various technology including single-cell RNA sequencing of gut and brain tissue. ResultsThe results suggested that NPs showed a better ability to induce gut macrophage activation than did MPs. In addition, NPs triggered gut interleukin 1 beta (IL-1{beta})-producing macrophage reprogramming via inducing lysosomal damage after phagocytosis. More importantly, IL-1{beta} released from the intestine could affect brain immunity, leading to microglial activation and Th17 differentiation, all of which correlated with a decline in cognitive and short-term memory in NPs-fed mice ConclusionsThus, this study provides new insight into the mechanism of action of the gut-brain axis and delineates the way NPs reduce brain function, highlights the importance to fix the plastic pollution problem worldwide.

immunology↗

RBP45d is required for 5' splice site selection via binding to intronic U-rich elements and interaction with PRP39a in Arabidopsis thaliana

A large number of cryptic splice sites in eukaryotic genome are generally dormant unless activated by mutations of authentic splice sites or splicing factors. How cryptic splice sites are used remains unknown in plants. Here, we identified two cryptic splicing regulators, RBP45d and PRP39a that are homologs of yeast U1 auxiliary protein Nam8 and Prp39, respectively, via genetic screening for suppressors of the virescent sot5 mutant, which results from a point mutation at the 5 splice site (5 ss) of intron 7. PCR and DNA sequencing data showed that loss-of-function mutations in RBP45d and PRP39a significantly increase the level of a cryptically spliced mRNA that encodes a mutated but partially functional sot5 protein, rescuing sot5 to the WT phenotype. Yeast two hybrid and bimolecular fluorescence complementation assays demonstrated that RBP45d and PRP39a interact each other and also with the U1C, a core subunit of U1 small nuclear ribonucleoprotein (U1 snRNP). RNA electronic mobility shift assay showed that RBP45d directly binds to the uridine (U)-rich RNA sequence downstream of the cryptic 5 ss. Consistently, our transcriptomic analysis revealed that a set of introns with U-rich sequences are retained in rbp45d. However, we found that other RBP45/47 members do not function redundantly with RBP45d, at least in regulation of cryptic splicing. Collectively, our data suggest that RBP45d is required for 5 ss selection via binding to intronic U-rich elements and PRP39a in plants. One sentence summaryThe Arabidopsis RBP45d interacting with U1C and PRP39a is required for 5 ss selection via binding to intronic U-rich elements.

plant biology↗

Propagation dynamics of electrotactic motility in large epithelial cell sheets

Directional migration initiated at the wound edge leads epithelial sheets to migrate in wound healing. How such coherent migration is achieved is not well understood. Here we used electric fields to induce robust migration of sheets of human keratinocytes and developed an in silico model to characterize initiation and propagation of epithelial collective migration. Electric fields initiate increase in migrations directionality and speed at the leading edge. The increases propagate across the epithelial sheets, resulting in directional migration of cell sheets as coherent units. Both the experimental and in silico models demonstrated vector-like integration of the electric and default directional cues at the free edge in space and time. The resultant collective migration is remarkably consistent in experiments and modeling, both qualitatively and quantitatively. The keratinocyte model thus faithfully reflects key features of epithelial migration as a coherent tissue in vivo, e.g. that leading cells lead, and that epithelium maintains cell- cell junction.

cell biology↗

Intestinal Epithelial Heat Shock Protein 25/27 integrates host and microbial drivers of mucosal restitution following inflammatory injury

Mucosal healing following inflammatory injury is poorly understood and often neglected, despite being the best indicator of long-term outcomes in inflammatory bowel diseases. We report here that the enigmatic small molecular weight heat shock protein, Hsp25 (the human form is Hsp27), plays a vital role in converging microbial and host factors to promote pSTAT3-mediated mucosal healing. In wild type mice, the proximal-to-distal gradient of intestinal epithelial cell (IEC) Hsp25 expression is dependent on microbial cues. Patients with left-sided ulcerative colitis, however, show reduced levels of Hsp27 expression in both uninvolved and involved areas compared to normal colons of non-IBD patients. In mice with global or IEC-specific Hsp25 gene-targeted deletion, impaired mucosal healing with development of hallmarks of chronic disease are observed following DSS-induced or TNBS-induced colitis, whereas mucosal restitution is accelerated in IEC-specific overexpressing Hsp25 transgenic mice. In colonic IECs derived from these murine lines, Hsp25 binds and stabilizes a phospho-STAT3/YAP nuclear complex stimulated by IL-22 to sustain its wound healing gene programming. Thus, our findings provide insight into the mechanism of action of IEC Hsp25/27 in integrating host and microbial drivers of mucosal restitution, which can be leveraged to develop novel approaches for achieving and maintaining remission in complex immune disorders like IBD.

pathology↗

Relation is an option for processing context information

Attention mechanisms are one of the most frequently used architectures in the development of artificial intelligence because they can process contextual information efficiently. Various artificial intelligence mechanisms such as transformer for processing natural language, image data, etc. include the attention mechanism. Since attention is a powerful component to realize artificial intelligence, various improvements have been made to enhance its performance. The time complexity of attention depends on the square of input sequence length. Methods to improve time complexity of attention are one of the hottest topics in various studies. In this study, we have devised a mechanism called relation that can understand the context information of sequential data without using attention. Relation is very simple to implement and its time complexity depends only on the length of the sequences; a comparison of the performance of neural networks with relation and attention mechanisms on several benchmark datasets shows that relation achieved the same context processing capability as attention with less computation time. Hence, relation is an ideal option for processing context information.

neuroscience↗

High Quality Phasing Using Linked-Read Whole Genome Sequencing of Patient Cohorts Informs Genetic Understanding of Complex Traits

Phasing of heterozygous alleles is critical for interpretation of cis-effects of disease-relevant variation. For population studies, phase is often inferred from external data but read-based phasing approaches that span long genomic distances would be more accurate because they enable both genotype and phase to be obtained from a single dataset. To demonstrate how read-based phasing can provide functional insights, we sequenced 477 individuals with Cystic Fibrosis (CF) using linked-read sequencing. We benchmark read-based phasing with different short- and long-read sequencing technologies, prioritize linked-read technology as the most informative and produce a benchmark phase call set from reference sample HG002 for the community. The 477 samples display an average phase block N50 of 4.39 Mb. We use these samples to construct a graph representation of CFTR haplotypes, which facilitates understanding of complex CF alleles. Fine-mapping and phasing of the chr7q35 trypsinogen locus associated with CF meconium ileus demonstrates a 20 kb deletion and a PRSS2 missense variant p.Thr8Ile (rs62473563) independently contribute to meconium ileus risk (p=0.0028, p=0.011, respectively) and are PRSS2 pancreas eQTLs (p=9.5e-7 and p=1.4e-4, respectively), explaining the mechanism by which these polymorphisms contribute to CF. Phase enables access to haplotypes that can be used for genome graph or reference panel construction, identification of cis-effects, and for understanding disease associated loci. The phase information from linked-reads provides a causal explanation for variation at a CF-relevant locus which also has implications for the genetic basis of non-CF pancreatitis to which this locus has been reported to contribute.

genetics↗

Global Spatial Transcriptome of Macaque Brain at Single-Cell Resolution

Global profile of gene expression at single-cell resolution remains to be determined for primates. Using a recently developed technology ("Stereo-seq"), we have obtained a comprehensive single-cell spatial transcriptome map at the whole-brain level for cynomolgus monkeys, with [~]600 genes per cell for 10 m-thick coronal sections (up to 15 cm2 in size). Large-scale single-nucleus RNA-seq analysis for [~]1 million cells helped to identify cell types corresponding to Stereo-seq gene expression profiles, providing a 3-D cell type atlas of the monkey brain. Quantitative analysis of Stereo-seq data revealed molecular fingerprints that mark distinct neocortical layers and subregions, as well as domains within subcortical structures including hippocampus, thalamus, striatum, cerebellum, hypothalamus and claustrum. Striking whole-brain topography and coordinated patterns were found in the expression of genes encoding receptors and transporters for neurotransmitters and neuromodulators. These results pave the way for cellular and molecular understanding of organizing principles of the primate brain.

cell biology↗