Biology subjects

Fan, Y.

Publications and source records attributed to Fan, Y..

At least 253 records · Page 14Linked to original sources

bioRxiv2020

Mesenchymal stem cells with overexpression of Angiotensin-converting enzyme-2 improved the microenvironment and cardiac function in a rat model of myocardial infarction

BackgroundAngiotensin-converting enzyme-2 (ACE2) overexpression improves left ventricular remodeling and function in diabetic cardiomyopathy; however, the effect of ACE2-overexpressed mesenchymal stem cells (MSCs) on myocardial infarction (MI) remains unexplored. This study aimed to investigate the effect of ACE2-overexpression on the function of MSCs and the therapeutic efficacy of MSCs for MI. MethodsMSCs were transfected with Ace2 gene using lentivirus, and then transplanted into the border zone of ischemic heart. The renin-angiotensin system (RAS) expression, nitric oxide synthase (NOS) expression, paracrine factors, anti-hypoxia ability, tube formation of MSCs, and heart function were determined. ResultsMSCs expressed little ACE2. ACE2-overexpression decreased the expression of AT1 and VEGF apparently, up-regulated the paracrine of HGF, and increased the synthesis of Angiotensin 1-7 in vitro. ACE2-overexpressed MSCs showed a cytoprotective effect on cardiomyocyte, and an interesting tube formation ability, decreased the heart fibrosis and infarct size, and improved the heart function. ConclusionTherapies employing MSCs with ACE2 overexpression may represent an effective treatment for improving the myocardium microenvironment and the cardiac function after MI.

pharmacology and toxicology↗

bioRxiv2020

YTHDF2 is essential for spermatogenesis and fertility through mediating a wave of transcript transition during spermatogonial differentiation

The dynamic and reversible regulation roles of m6A modification, and the characterization of m6A readers have provided new insights into spermatogenesis at post-transcriptional level. YTHDF2 has been reported to recognize and mediate the m6A-containing transcripts decay during the mouse oocyte mature, embryonic stem cell differentiation, neural development, and zebrafish maternal-to-zygotic transition. However, the roles of YTHDF2 in mammalian spermatogenesis are uncertain. Here, we generated germ cell-specific Ythdf2 mutants (Ythdf2-vKO) at a C57BL/6J background, and demonstrated that YTHDF2 was essential for mouse spermatogenesis and fertility. Ythdf2-vKO provided oligoasthenoteratozoospermia (OAT) phenotype with increased apoptosis in germ cells. High-throughput RNA-seq of the testis tissue showed the failure of the degradation of a wave of YTHDF2 target mRNA. Interestingly, RNA-seq analysis combined with our previous single-cell transcriptomics data of mouse spermatogenesis pointed out the failure of a wave of transcript transition during the spermatogenesis of Ythdf2-vKO, which was confirmed by gene expression analysis of diplotene spermatocytes and round spermatids obtained through fluorescence-activated cell sorting using qPCR. Our study demonstrates the fundamental role of YTHDF2 during mouse spermatogenesis and provides a potential candidate for the diagnosis of male infertility with OAT syndrome. Author summaryMale infertility is becoming a worldwide health problem. Male gamete is generated through spermatogenesis, which is a complicated developmental process with dynamic transcriptome changes. RNA m6A modification has been reported as the most prominently internal mRNA modification, which control the tune of gene expression through mRNA splicing, export, translation and decay. RNA m6A modification is catalyzed by "writers", and could be removed by "erasers". The m6A modification enzymes are reported to play important roles during spermatogenesis. Given that the biological function of m6A modification are mediated through its "readers", its readers might be proposed to be involved in the regulation of spermatogenesis. YTHDF2, as a reader of m6A modification, has been reported to mediate the m6A-containing transcripts decay. To explore the roles of YTHDF2 in spermatogenesis, we used germ cell-specific mutation strategy to knock out the mouse Ythdf2. The mutants provided oligoasthenoteratozoospermia phenotype. Our study demonstrate that YTHDF2 is essential for mouse spermatogenesis. YTHDF2 could be a potential candidate for the diagnosis of oligoasthenoteratozoospermia syndrome.

genetics↗

bioRxiv2020

In-field bioreactors demonstrate dynamic shifts in microbial communities in response to geochemical perturbations.

Subsurface microbial communities mediate the transformation and fate of redox sensitive materials including organic matter, metals and radionuclides. Few studies have explored how changing geochemical conditions influence the composition of groundwater microbial communities over time. We temporally monitored alterations in abiotic forces on microbial community structure using 1L in-field bioreactors receiving background and contaminated groundwater at the Oak Ridge Reservation, TN. Planktonic and biofilm microbial communities were initialized with background water for 4 days to establish communities in triplicate control reactors and triplicate test reactors and then fed filtered water for 14 days. On day 18, three reactors were switched to receive filtered groundwater from a contaminated well, enriched in total dissolved solids relative to the background site, particularly chloride, nitrate, uranium, and sulfate. Biological and geochemical data were collected throughout the experiment, including planktonic and biofilm DNA for 16S rRNA amplicon sequencing, cell counts, total protein, anions, cations, trace metals, organic acids, bicarbonate, pH, Eh, DO, and conductivity. We observed significant shifts in both planktonic and biofilm microbial communities receiving contaminated water. This included a loss of rare taxa, especially amongst members of the Bacteroidetes, Acidobacteria, Chloroflexi, and Betaproteobacteria, but enrichment in the Fe- and nitrate-reducing Ferribacterium and parasitic Bdellovibrio. These shifted communities were more similar to the contaminated well community, suggesting that geochemical forces substantially influence microbial community diversity and structure. These influences can only be captured through such comprehensive temporal studies, which also enable more robust and accurate predictive models to be developed.

microbiology↗

bioRxiv2020

Comprehensive transcriptome data of normal and Ascosphaera apis-infected western honeybee larval guts

ABSTRAmTApis mellifera ligustica is a well-known subspecies of western honeybee, Apis mellifera. Ascosphaera apis is a common fungal pathogen of honeybee larvae, resulting in Chalkbrood disease. In this article, deep sequencing of un-treated 4-, 5-, and 6-day-old larval guts (AmCK1, AmCK2, AmCK3) and A. apis-treated 4-, 5- and 6-day-old larval guts (AmT1, AmT2, AmT3) of Apis mellifera ligustica were conducted using Illumina HiSeq 4000 platform. In total, 85811046, 81962296, 85636572, 79267686, 82889882, and 100211796 raw reads were respectively yielded from above-mentioned six groups. The result of sequencing satuation analysis suggested that the sequencing depth in this work was enough to detect nearly all expressed genes. After quality control, 85739414, 81896402, 85573798, 79202304, 82828926, and 100128692 clean reads were obtained. Additionally, the GC content of each group was above 45.26%. Furthermore, 47035852, 65612676, 71803878, 62560904, 65018360, and 56278272 clean reads were mapped to the Apis mellifera genome, including 41221479, 61172916, 66724233, 57531335, 60245732, and 52638986 unique mapped clean reads, and 2078427, 986825, 915375, 1082925, 1097130, and 716436 multiple mapped clean reads. In addition, exons were the most abundant regions mapped by clean reads, follow by intergenic regions and introns. The strand-specific cDNA library-based RNA sequencing data documented here will faciliate study on molecualr mechanisms underlying host immune response and host-pathogen interaction during chalkbrood disease, and benefit understanding of non-coding RNA-mediated cross-kingdom regulation between A. m. ligustica larvae and A. apis. Value of the DataO_LIThis data reported here could be used to explore circRNAs, lncRNAs, mRNAs and their competing endogenous RNA networks involved in response of western honeybee larvae to Ascosphaera apis infection. C_LIO_LIThe current data contributes to better understanding mechanisms regulating host-pathogen interaction during chalkbrood disease. C_LIO_LIOur data can provide novel insights into understanding non-coding RNA-mediated cross-kingdom regulation between Apis mellifera ligustica and A. apis. C_LI

molecular biology↗

bioRxiv2020

Role of short-chain fatty acids in the gut-brain axis in schizophrenia: contribution to immune activation and pathophysiology in humans and mice

ObjectiveGut microbiota dysbiosis and aberrant gut-brain functional modules including short-chain fatty acid (SCFA) production and long-lasting immune activation (IA) are presented in schizophrenia. Given the key roles of gut microbiota and SCFA in shaping immunity, we propose that dysbiosis-induced SCFA upregulation could contribute to IA and behavioral symptoms in schizophrenia. DesignGut microbiota, SCFA, and IA biomarkers were compared between schizophrenic patients and healthy controls. The roles of SCFA in schizophrenia-related IA were analyzed in cultured peripheral blood mononuclear cells (PBMCs) and a mouse model of schizophrenia. The effects of SCFAs on schizophrenia-related phenotypes were analyzed in both human and mouse. ResultsBoth microbial-derived SCFA and SCFA-producing bacteria were elevated in the guts of schizophrenic patients, and this increased SCFA production in gut was associated with IA in schizophrenia. The microbiome signature underpinning schizophrenia-related IA includes increased diversity and increased SCFA-producing bacteria and inflammation-associated bacteria. The impact of SCFAs on immune responses of cultured PBMC depend on the diagnosis and IA status of donors. Small-molecule serum filtrates from immune-activated schizophrenic patients increased the inflammatory response of PBMCs from healthy volunteers, which can be enhanced and attenuated by SCFAs supplementation and inhibition of SCFA signaling, respectively. Chronically elevated SCFAs in adolescence induced neuroinflammation and schizophrenia-like behaviors in adult mice. Moreover, chronically elevated SCFAs in adult mice prenatally exposed to IA potentiated their expression of schizophrenia-like behaviors. Conclusionmicrobiota-derived SCFAs are important mediators of dysregulated gut-brain axis and participant in pathogenesis via enhance IA in schizophrenia. SummaryO_ST_ABSSignificance of this studyC_ST_ABSO_LIWhat is already known about this subject? [tpltrtarr]Schizophrenia pathogenesis goes beyond the brain since increasing peripheral abnormalities are revealed including gut microbiota dysbiosis, GI dysfunction, and systemic immune activation (IA). [tpltrtarr]Systemic IA/inflammation contributes to the neuroinflammation and brain impairment underlying schizophrenia, and adjunctive immunotherapy can improve psychotic symptoms. [tpltrtarr]Short-chain fatty acids (SCFA) mediate the microbiota-gut-brain communication and modulate several pathways involved in schizophrenia, including pathways of immunity and neurotransmitters. C_LIO_LIWhat are the new findings? [tpltrtarr]Patients with schizophrenia displayed increased rates of IA and increased SCFA production compared with healthy controls, and increased SCFA is associated with IA in patients. [tpltrtarr]A unique microbiota signature including enriched SCFA-producing bacterial species can distinguish patients with IA from other patients and controls. [tpltrtarr]Small molecules in the serum of immune-activated patients with schizophrenia enhance LPS-induced immune response of cultured peripheral blood mononuclear cell (PBMCs), which is partially mediated by SCFA signaling. [tpltrtarr]SCFA intake upregulates both peripheral and brain inflammation and potentiates the expression of schizophrenia-like behaviors in mice prenatally exposed to IA. C_LIO_LIHow might it impact on clinical practice in the foreseeable future? [tpltrtarr]Interference of SCFA signaling or targeted destruction of SCFA-producing bacteria may provide a new approach for the prevention and treatment of schizophrenia. [tpltrtarr]Immune activation status of patients should be an important condition considered when selecting immunotherapy for future precision psychiatric therapy. C_LI

neuroscience↗

bioRxiv2020

Strand-specific cDNA library-based RNA sequencing dataset of un-infected and Ascosphaera apis-infected larval guts of Apis cerana cerana

Apis cerana cerana is a subspecies of eastern honeybee, Apis cerana. Ascosphaera apis is a widespread fungal pathogen of honeybee, leading to chalkbrood, which results in heavy losses for beekeeping industry. In this article, 4-, 5-, and 6-day-old larval guts of un-infected (AcCK1, AcCK2, and AcCK3) and A. apis-infected A. c. cerana (AcT1, AcT2, and AcT3) were sequenced by next generation sequencing. Totally, 73830148, 96586212, 94552744, 76672564, 90954858, and 83418832 raw reads were respectively produced from AcCK1, AcCK2, AcCK3, AcT1, AcT2, and AcT3. The sequencing depth was enough to detect all expressed genes. After strict quality control, 73775592, 96513798, 94495000, 76593924, 90870608 and 83339288 clean reads were obtained, with a mean GC content of 48.54%. Additionally, average Q20 and Q30 for aforementioned six groups were 98.10% and 94.36%, respectively. Moreover, 45302685, 65872823, 52709987, 49947838, 56476339, and 42657156 clean reads from above-mentioned six groups were mapped to the reference genome of Apis cerana, respectively. In addition, exons were the most abundant regions in reference genome mapped by clean reads, followed by intergenic regions and introns. Our data presented here can be used to identify long non-coding RNAs (lncRNAs), circlular RNAs (circRNAs), mRNAs and their regulatory networks engaged in response of eastern honeybee larvae to A. apis infection, and decipher molecular mechanisms underlying host-pathogen interaction. Value of the DataO_LIThe current data can be used for exploration of mRNAs, lncRNAs, circRNAs and their competing endogenous RNA (ceRNA) networks engaged in response of A. c. cerana larvae to A. apis infection. C_LIO_LIThis data provides a valuable genetic resource for better understanding non-coding RNA-mediated cross-kingdom regulation of eastern honey larvae to A. apis. C_LIO_LIThe accessible data offers novel insights into understanding the molecular mechanism underlying interaction between eastern honeybee larvae and A. apis. C_LI

bioinformatics↗

bioRxiv2020

The histone deacetylase complex MiDAC regulates a neurodevelopmental gene expression program

MiDAC is a recently identified histone deacetylase (HDAC) complex. While other HDAC complexes have been implicated in neurogenesis, the physiological role of MiDAC remains unknown. Here, we show that MiDAC constitutes an important regulator of neural differentiation. We demonstrate that MiDAC functions as a modulator of a neurodevelopmental gene expression program and binds to important regulators of neurite outgrowth. On the one hand, MiDAC upregulates gene expression by mediating the removal of H4K20ac on the promoters and enhancers of pro-neural genes such as those encoding the secreted ligands SLIT3 and NETRIN1 (NTN1). Conversely, MiDAC inhibits gene expression by reducing H3K27ac on promoter-proximal and -distal elements of negative regulators of neurogenesis. Furthermore, loss of MiDAC results in neurite outgrowth defects that can be rescued by supplementation with SLIT3 and/or NTN1. These findings indicate a crucial role for MiDAC in regulating the ligands of the SLIT3 and NTN1 signaling axes to ensure the proper integrity of neurite development.

molecular biology↗

bioRxiv2020

Pacific Biosciences long reads-based genome sequencing data from a widespread bee fungal parasite, Nosema ceranae

Nosema ceranae is a widespread fungal parasite that infects both adult honeybee and honeybee larvae, leading to microsporidiosis, which seriously affects bee health and apicultural industry. In this article, genome sequencing of clean spores of N. ceranae was conducted using third-generation Pacific Biosciences (PacBio) single molecule real time (SMRT) sequencing technology. In total, 152671 subreads were obtained after quality control of raw reads from PacBio SMRT sequencing, with a N50 and average length of 14422 bp and 11310 bp, respectively. Additionally, the length distribution of subreads was from 10000 bp to more than 50000 bp. Nineteen scaffords with a total length of 7354221 bp were assembled, and the N50, N90 and maximum scafford length were 728543 bp, 198795 bp and 1917792 bp, respectively. The GC content was 25.97%. Furthermore, by integration of genes predicted from de novo and homology-based methods, 3112 N. ceranae genes were finally assembled, with a total length of 2730179 bp and mean length of 877.31 bp. In addition, the total length and mean length of exons were 2657637 bp and 854 bp, respectively; and the total length and mean length of introns were 72542 bp and 23.31 bp, respectively. The genome sequencing data documented here will give deep insights into the molecular biology of N. ceranae, facilitate exploration of genes and pathways associated with toxin factors and infection-related factors, and benefit research on comparative genomics and phylogenetic diversity of Nosema species.

bioinformatics↗

bioRxiv2020

Genome-wide bisulfite sequencing data of normal and Ascosphaera apis-infected larval guts of eastern honeybee

Apis cerana cerana, a subspecies of eastern honey, Apis cerana, plays a specific role in beekeeping industry and ecosystem in China and other Asian countries. Larvae of A. c. cerana can be infected by Ascosphaera apis, the fungal pathogen of chalkbrood. In this article, normal 4-, 5-, and 6-day-old larval guts (AcCK1, AcCK2, AcCK3) and A. apis-infected 4-, 5- and 6-day-old larval guts (AcT1, AcT2, AcT3) of A. c. cerana workers were respectively harvested followed by DNA isolation, bisulfite conversion, cDNA library construction and Illumina sequencing. Based on genome-wide bisulfite sequencing, 79167210, 82175052, 79331489, 81051009, 74742842 and 74849091 raw reads were generated from AcCK1, AcCK2, AcCK3, AcT1, AcT2 and AcT3, and after quality control, 73417030 (92.73%), 76660370 (93.27%), 71804727 (90.44%), 75046507 (92.82%), 67487782 (90.30%) and 67367023 (90.04%) clean reads were obtained, respectively. Additionally, 73333333, 76533333, 71466667, 75066667, 67590965 and 67200000 clean reads were mapped to the reference genome of A. cerana, including 54656767, 58583415, 54127407, 57943220, 52547867 and 51295824 unique mapped clean reads, and 8624392, 8789458, 7531333, 7747337, 6249679 and 5394174 multiple mapped clean reads. The genome-wide bisulfite sequencing data reported here can be used for genome-wide identification of 5mC methylation sites in eastern honeybee larval guts and systematic investigation of DNA methylation-mediated host response to A. apis infection. Value of the dataO_LIThe current dataset contributes to genome-wide identification of 5mC methylation sites in normal and A. apis-infected larval guts of eastern honeybee. C_LIO_LIThe reported data could be used for systematic investigation of DNA methylation-mediated response of eastern honeybee larvae to A. apis infection. C_LIO_LIOur data offers a valuable genetic resource for better understanding epigenetic regulation mechanism involved in eastern honeybee larvae-A. apis interaction. C_LI

molecular biology↗

bioRxiv2020

Whole genome bisulfite sequencing dataset of mycelium and spore of chalkbrood disease pathogen Ascosphaera apis

Chalkbrood, a widespread fungal disease of bee larvae, is caused by the fungus Ascosphaera apis. In this article, mecylia and spores of A. apis were respectively collected followed by DNA isolation, bisulfite conversion, cDNA library construction and next-generation sequencing. Using whole genome bisulfite sequencing (WGBS), 69,844,360 and 60,570,990 raw reads were yielded from Aam and Aas, and after quality control, 9,982,386,951 and 8,825,601,434 clean reads were obtained, respectively. In addition, 67,685,866 and 58,886,072 clean reads were mapped to the reference genome of A. apis, including 37,643,592 and 31,568,442 unique mapped clean reads, and 49,686 and 13,348 multiple mapped clean reads. Furthermore, after bisulfite treatment, the conversion ratio of clean reads from Aam and Aas were 99.38% and 99.51%, respectively. The WGBS data ducumented here contributes to genome-wide identification of 5mC methylation sites in A. apis and comparison of methylomes between mycelium and spore. Value of the dataO_LIThis dataset can be used for genome-wide identification of 5mC methylation sites in A. apis. C_LIO_LIThe accessible data could be used to systematically compare methylomes between mycelium and spore of A. apis. C_LIO_LICurrent data provides a useful resource for further study on DNA methylation-mediated mechanism underlying mycelium growth, spore germination and sexual reproduction of mycelium with the opposite sex. C_LI

molecular biology↗

bioRxiv2020

Nanopore-based long-read transcriptome data of Nosema ceranae-infected and un-infected western honeybee workers' midguts

Apis mellifera ligustica is a subspecies of western honeybee, Apis mellifera. Nosema ceranae is known to cause bee microspodiosis, which seriously affects bee survival and colony productivity. In this article, Nanopore long-read sequencing was used to sequence N. ceranae-infected and un-infected midguts of A. m. ligustica workers at 7 d and 10 d post inoculation (dpi). In total, 5942745, 6664923, 7100161 and 6506665 raw reads were respectively yielded from AmT1, AmT2, AmCK1 and AmCK2, with average lengths of 1148, 1196, 1178 and 1201 bp, and N50 of 1328, 1394, 1347 and 1388 bp. The length distribution of raw reads from AmT1, AmT2, AmCK1 and AmCK2 was ranged from 1 kb to more than 10 kb. Additionally, the distribution of quality score of raw reads from AmT1 and AmT2 was among Q6[~]Q12, while that from AmCK1 and AmCK2 was among Q6[~]Q16. Further, 5745048, 6416987, 6928170, 6353066 clean reads were respectively gained from AmT1, AmT2, AmCK1 and AmCK2, and among them 4172542, 4638289, 5068270 and 4857960 were identified as being full-length. After removing redundant reads, the length distribution of remaining full-length transcripts was among 1 kb[~]8 kb, with the most abundant length of 2 kb. The long-read transcriptome data reported here contributes to a deeper understanding of the molecular regulating N. ceranae-response of A. m. ligustica and host-fungal parasite interaction during microsporidiosis.

bioinformatics↗

bioRxiv2020

A full-length transcriptome dataset of normal and Nosema ceranae-challenged midgut tissues of eastern honeybee workers

Apis cerana cerana is a subspecies of eastern honeybee, Apis cerana, and it plays a vital role in ecological maintenance in China. However, A. c. cerana is threatened by many pathogenic microorganisms including Nosema ceranae, a widespread fungal parasite that infected worldwide colonies. In this article, un-challenged (AcCK1, AcCK2) and N. ceranae-challenged midguts of A. c. cerana workers (AcT1, AcT2) were sequenced utilizing Nanopore long-read sequencing technology. Totally, 11,727,628, 6,996,395, 14,383,735 and 11,580,154 raw reads were yielded from AcCK1, AcCK2, AcT1 and AcT2; the average lengths were 1147 bp, 908 bp, 992 bp and 1077 bp, and the average N50 were 1308 bp, 911 bp, 1079 bp and 1192 bp. The length distribution of was ranged 1 kb to more than 10 kb. Additionally, the quality (Q) score distribution of raw reads was among Q7~Q17. Further, 11,617,144, 6,940,895, 14,277,240 and 11,501,562 clean reads were respectively obtained from AcCK1, AcCK2, AcT1 and AcT2, and among them 78.40%, 82.50%, 79.05% and 80.20% were identified as full-length clean reads. In addition, full-length clean reads from AcCK1, AcT1, AcT2 and AcCK2 were ranged from 1 kb to more than 10 kb in length. Finally, the length distribution of redundant reads-removed full-length transcripts was among 1 kb~5 kb. Value of the data{diamondsuit} This dataset enables better understanding the complexity of A. c. cerana transcriptome. {diamondsuit}Current dataset contributes to identification of genes and transcripts engaged in response of eastern honeybee to N. ceranae stress. {diamondsuit}The data provides a valuable genetic resource for deciphering alternative splicing and polyadenylation of A. c. cerana mRNAs involved in host response to N. ceranae challenge. {diamondsuit}The reported data is beneficial for uncovering the molecular mechanism regulating interaction between eastern honeybee and microsporidian.

molecular biology↗

bioRxiv2020

PacBio SMRT-based full-length transcriptome data of Ascosphaera apis mycelium and spore

Ascosphaera apis is an entomopathogenic fungus that exclusively infects honeybee larvae, resulting in chalkbrood disease, a widespread fungal disease damaging the beekeeping industry all over the world. In this article, purified mycelia (Aam) and spores (Aas) of A. apis pure culture under lab condition were sequenced using PacBio Sequel platform. In total, 13,302,489 and 9,911,345 subreads were yielded from Aam and Aas, respectively; 394,142 and 274,928 circular consensus sequence (CCS) reads were identified as being full-length non-chimeric (FLNC) reads, with a mean length of 2820 bp and 2602 bp, respectively. Furthermore, 174,095 and 103,845 corrected isoforms were identified, with a N50 length of 3543 bp and 3262 bp, respectively. The reported full-length transcriptome data of A. apis mycelium and spore will provide a valuable resource for improvement of genome and transcriptome annotations as well as better understanding of transcript structure such as alternative splicing and polyadenylation. Value of the dataO_LICurrent dataset offers a set of high-quality full-length transcripts of A. apis. C_LIO_LIThe data can facilitate the improvement of A. apis genome and transcriptome annotations. C_LIO_LIThis dataset benefits further exploration of alternative splicing and polyadenylation of A. apis mRNAs. C_LI

evolutionary biology↗

bioRxiv2020

Long-read transcriptome data of bee fungal parasite, Nosema ceranae

Nosema ceranae, a widespread fungal parasite that infects honeybee and many other bee species, can seriously affect bee health and colony productivity. In this article, N. ceranae spores were purified followed by third-generation sequencing using Nanopore PromethION platform. Totally, 6988795 raw reads were yielded from purified spores, with a length distribution among 1 kb~10 kb and a quality (Q) score distribution among Q6~Q12. A total of 6953469 clean reads were obtained, and among them 73.98% were identified as being full-length. The length of redundant reads-removed full-length transcripts was ranged from 1 kb to 5 kb, with the most abundant length of 1 kb. These data will improve transcriptome quality of N. ceranae significantly.

bioinformatics↗

bioRxiv2020

DAZL mediates a broad translational program regulating expansion and differentiation of spermatogonial progenitors

Fertility across metazoa requires the germline-specific DAZ family of RNA-binding proteins. Here we examine whether DAZL directly regulates progenitor spermatogonia using a conditional genetic mouse model and in vivo biochemical approaches combined with chemical synchronization of spermatogenesis. We find that the absence of Dazl impairs both expansion and differentiation of the spermatogonial progenitor population. In undifferentiated spermatogonia, DAZL binds the 3 UTRs of [~]2,500 protein-coding genes. Some targets are known regulators of spermatogonial proliferation and differentiation while others are broadly expressed, dosage-sensitive factors that control transcription and RNA metabolism. DAZL binds 3 UTR sites conserved across vertebrates at a UGUU(U/A) motif. By assessing ribosome occupancy in undifferentiated spermatogonia, we find that DAZL increases translation of its targets. In total, DAZL orchestrates a broad translational program that amplifies protein levels of key spermatogonial and gene regulatory factors to promote the expansion and differentiation of progenitor spermatogonia.

developmental biology↗

bioRxiv2020

Epitope-based peptide vaccines predicted against novel coronavirus disease caused by SARS-CoV-2

The outbreak of the 2019 novel coronavirus (SARS-CoV-2) has infected thousands of people with a large number of deaths across 26 countries. The sudden appearance of the virus leads to the limited existing therapies for SARS-CoV-2. Therefore, vaccines and antiviral medicines are in desperate need. This study took immune-informatics approaches to identify B- and T-cell epitopes for surface glycoprotein (S) of SARS-CoV-2, followed by estimating their antigenicity and interactions with the human leukocyte antigen (HLA) alleles. We identified four B cell epitopes, two MHC class-I and nine MHC class-II binding T-cell epitopes, which showed highly antigenic features. Allergenicity, toxicity and physiochemical properties analysis confirmed the specificity and selectivity of epitopes. The stability and safety of epitopes were confirmed by digestion analysis. No mutations were observed in all the selected B- and T-cell epitopes across all isolates from different locations worldwide. Epitopes were thus identified and some of them can be potential candidates for vaccine development.

immunology↗

bioRxiv2020

A plasmid locus associated with Klebsiella clinical infections encodes a microbiome-dependent gut fitness factor

Introductory paragraphGut colonization by the pathogen Klebsiella pneumoniae (Kp) is consistently associated with subsequent Kp disease1-5, and patients are predominantly infected with their colonizing strain1,2. However, colonizing strains likely vary in their potential to cause infection. We previously identified the plasmid-encoded tellurium resistance (ter) operon as highly associated with infection when compared to asymptomatic colonization in hospitalized patients1. The ter operon bestows resistance to the toxic compound tellurite oxide (TeO3-2), but this is unlikely to be its physiological function, as tellurium and TeO3-2 are exceedingly rare. Here we show that terC is necessary and terZABCDEF is sufficient for phenotypic TeO3-2 resistance. Next, we demonstrate that ter is encoded on a diverse group of plasmids without known plasmid-encoded virulence genes, suggesting an independent role in infection. Finally, our studies indicate that ter is a gut fitness factor, and its fitness advantage is conferred only when specific gut microbiota constituents are present. Collectively, these data reveal the Kp ter operon that is highly associated with human infection likely acts early in pathogenesis as a horizontally-transferrable fitness factor promoting robust gut colonization in the presence of the indigenous microbiota.

microbiology↗

bioRxiv2020

Regulation of T cell receptor signaling by protein acyltransferase DHHC21

S-acylation - reversible post-translational lipidation of cysteine residues - is emerging as an important regulatory mechanism in T cell signaling. Dynamic S-acylation is critical for protein recruitment into the T cell receptor complex and initiation of the subsequent signaling cascade. However, the enzymatic control of protein S-acylation in T cells remains poorly understood. Here, we report a previously uncharacterized role of DHHC21, a member of the mammalian family of DHHC protein acyltransferases, in regulation of the T cell receptor pathway. We found that loss of DHHC21 prevented S-acylation of key T cell signaling proteins, resulting in disruption of the early signaling events and suppressed expression of T cell activation markers. Furthermore, downregulation of DHHC21 prevented activation and differentiation of naive T cells into effector subtypes. Together, our study provides the first direct evidence that DHHC protein acyltransferases can play an essential role in regulation of T cell-mediated immunity.

cell biology↗