Biology subjects

Chen, D.

Publications and source records attributed to Chen, D..

At least 343 records · Page 19Linked to original sources

bioRxiv2020

Single-cell regulatory landscape and disease vulnerability map of adult Macaque cortex

Single cell approaches have increased our knowledge about the cell type composition of the non-human primate (NHP), but a detailed characterization of area-specific regulatory features remains outstanding. We generated single-cell chromatin accessibility (single-cell ATAC) and transcriptomic data of 358,237 cells from prefrontal cortex (PFC), primary motor cortex (M1) and primary visual cortex (V1) of adult cynomolgus monkey brain, and integrated this dataset with Stereo-seq (Spatio-Temporal Enhanced REsolution Omics-sequencing) of the corresponding cortical areas to assign topographic information to molecular states. We identified area-specific chromatin accessible sites and their targeted genes, including the cell type-specific transcriptional regulatory network associated with excitatory neurons heterogeneity. We reveal calcium ion transport and axon guidance genes related to specialized functions of PFC and M1, identified the similarities and differences between adult macaque and human oligodendrocyte trajectories, and mapped the genetic variants and gene perturbations of human diseases to NHP cortical cells. This resource establishes a transcriptomic and chromatin accessibility combinatory regulatory landscape at a single-cell and spatially resolved resolution in NHP cortex.

neuroscience↗

bioRxiv2020

A Novel System for The Comprehensive Collection of Nonvolatile Molecules from Human Exhaled Breath

Characterization of nonvolatile molecules in exhaled breath particles can be used for respiratory disease monitoring and diagnosis. Conventional methods for the collection of nonvolatile molecules in breath heavily rely on the physical properties of exhaled breath particles. Strategies taking advantage of their chemical properties have not yet been explored. In the present study, we developed a column system in which the surface chemistry between organic nonvolatile molecules and octadecyl carbon chain was exploited for the comprehensive collection of metabolites, lipids, and proteins. We demonstrated that the collection system had the capture efficiency of 99% and the capacity to capture representative nonvolatile molecules. The collection system was further evaluated using human subjects and proteins collected from human exhaled breath were characterized and identified using gel electrophoresis and bottom-up proteomics. The identified 303proteins from mass spectrometry were further searched against reported bronchoalveolar lavage fluid proteomes and it was shown that 60 proteins have the tissue origin of lower respiratory airways. In summary, we demonstrate that our collection system can collect nonvolatile molecules from human exhaled breath in an efficient and comprehensive manner and has the potential to be used for the study of respiratory diseases.

biochemistry↗

bioRxiv2020

Broad-spectrum antivirals of protoporphyrins inhibit the entry of highly pathogenic emerging viruses

Severe emerging and re-emerging viral infections such as Lassa fever, Avian influenza (AI), and COVID-19 caused by SARS-CoV-2 urgently call for new strategies for the development of broad-spectrum antivirals targeting conserved components in the virus life cycle. Viral lipids are essential components, and viral-cell membrane fusion is the required entry step for most unrelated enveloped viruses. In this paper, we identified a porphyrin derivative of protoporphyrin IX (PPIX) that showed broad antiviral activities in vitro against a panel of enveloped pathogenic viruses including Lassa virus (LASV), Machupo virus (MACV), and SARS-CoV-2 as well as various subtypes of influenza A viral strains with IC50 values ranging from 0.91{+/-}0.25 M to 1.88{+/-}0.34 M. A mechanistic study using influenza A/Puerto Rico/8/34 (H1N1) as a testing strain showed that PPIX inhibits the infection in the early stage of virus entry through biophysically interacting with the hydrophobic lipids of enveloped virions, thereby inhibiting the formation of the negative curvature required for fusion and blocking the entry of enveloped viruses into host cells. In addition, the preliminary antiviral activities of PPIX were further assessed by testing mice infected with the influenza A/Puerto Rico/8/34 (H1N1) virus. The results showed that compared with the control group without drug treatment, the survival rate and mean survival time of the mice treated with PPIX were apparently prolonged. These data encourage us to conduct further investigations using PPIX as a lead compound for the rational design of lipid-targeting antivirals for the treatment of infection with enveloped viruses.

pharmacology and toxicology↗

bioRxiv2020

Comprehensive structure-function characterization of DNMT3B and DNMT3A reveals distinctive de novo DNA methylation mechanisms

Mammalian DNA methylation patterns are established by two de novo DNA methyltransferases DNMT3A and DNMT3B, which exhibit both redundant and distinctive methylation activities. However, the related molecular basis remains undetermined. Through comprehensive structural, enzymology and cellular characterization of DNMT3A and DNMT3B, we here report a multi-layered substrate-recognition mechanism underpinning their divergent genomic methylation activities. A hydrogen bond in the catalytic loop of DNMT3B causes a lower CpG specificity than DNMT3A, while the interplay of target recognition domain and homodimeric interface fine-tunes the distinct target selection between the two enzymes, with Lysine 777 of DNMT3B acting as a unique sensor of the +1 flanking base. The divergent substrate preference between DNMT3A and DNMT3B provides an explanation for site-specific epigenomic alterations seen in ICF syndrome with DNMT3B mutations. Together, this study reveals crucial and distinctive substrate-readout mechanisms of the two DNMT3 enzymes, implicative of their differential roles during development and pathogenesis.

genetics↗

bioRxiv2020

Identification of a novel efficient transcriptional activation domain from Chinese fir (Cunninghamia lanceolata)

Activation domains are used as critical components of artificial gene modification tools for genetic breeding. The high efficiency of the activation domain relies on the host plant. However, no activation domain has been identified that originates from Chinese fir (Cunninghamia lanceolate). In this study, a novel strong activator was identified from the whole Chinese fir cDNA library. This plant conserved activator was named TAC 3 (Transcriptional Activation domain from Chinese fir 3). C-terminal 70 amino acids of TAC (TAC3d) have a stronger ability than the commonly used strong activation domain of the virus protein VP16, or the strong plant activation domain, EDLL, in Chinese fir. Through Dual-luciferase assay, phenomic analysis and FT (Flowering Locus T [FT]) quantification, it was shown that, TAC3d can overcome the transcriptional repression of strong plant repressors (Flowering Locus C [FLC]) when fused to its C-terminal domain, thus inhibit the repression of FT expression. In conclusion, for the first time, an activation domain has been identified from Chinese fir. TAC3, which can be used for precise gene activation in Chinese fir in the future, and its function in the plant is more powerful than the commonly used strong activation domain (such as VP16 and EDLL). HighlightTAC3 is the first transcriptional activation domain identified from Chinese fir and its function is more powerful than some commonly used strong transcriptional activators (such as VP16 and EDLL)

genetics↗

bioRxiv2020

Broad and differential animal ACE2 receptor usage by SARS-CoV-2

The COVID-19 pandemic has caused an unprecedented global public health and economy crisis. The origin and emergence of its causal agent, SARS-CoV-2, in the human population remains mysterious, although bat and pangolin were proposed to be the natural reservoirs. Strikingly, comparing to the SARS-CoV-2-like CoVs identified in bats and pangolins, SARS-CoV-2 harbors a polybasic furin cleavage site in its spike (S) glycoprotein. SARS-CoV-2 uses human ACE2 as its receptor to infect cells. Receptor recognition by the S protein is the major determinant of host range, tissue tropism, and pathogenesis of coronaviruses. In an effort to search for the potential intermediate or amplifying animal hosts of SARS-CoV-2, we examined receptor activity of ACE2 from 14 mammal species and found that ACE2 from multiple species can support the infectious entry of lentiviral particles pseudotyped with the wild-type or furin cleavage site deficient S protein of SARS-CoV-2. ACE2 of human/rhesus monkey and rat/mouse exhibited the highest and lowest receptor activity, respectively. Among the remaining species, ACE2 from rabbit and pangolin strongly bound to the S1 subunit of SARS-CoV-2 S protein and efficiently supported the pseudotyped virus infection. These findings have important implications for understanding potential natural reservoirs, zoonotic transmission, human-to-animal transmission, and use of animal models. ImportanceSARS-CoV-2 uses human ACE2 as primary receptor for host cell entry. Viral entry mediated by the interaction of ACE2 with spike protein largely determines host range and is the major constraint to interspecies transmission. We examined the receptor activity of 14 ACE2 orthologues and found that wild type and mutant SARS-CoV-2 lacking the furin cleavage site in S protein could utilize ACE2 from a broad range of animal species to enter host cells. These results have important implications in the natural hosts, interspecies transmission, animal models and molecular basis of receptor binding for SARS-CoV-2.

microbiology↗

bioRxiv2020

Epigenetic regulator BMI1 promotes fusion-positive rhabdomyosarcoma proliferation and constitutes a novel therapeutic target

Rhabdomyosarcoma (RMS) is an aggressive pediatric soft tissue sarcoma that continues to present significant challenges to pediatric oncology. There are two major subtypes of pediatric rhabdomyosarcoma, alveolar and embryonal. Alveolar rhabdomyosarcomas are characterized by the presence of a PAX-FOXO1 fusion protein and termed fusion-positive (FP-RMS); embryonal rhabdomyosarcomas (ERMS) lack these fusions and are termed fusion-negative (FN-RMS). Fusion-positive rhabdomyosarcoma (FP-RMS) harbors PAX-FOXO1 fusion proteins and has a worse overall outcome compared to FN-RMS, underscoring the critical need to identify novel targets for this disease. While fusion proteins remain challenging therapeutic targets, recent studies have begun to reveal the key intersection of PAX-FOXO1 fusion proteins with the malignant epigenome, suggesting that epigenetic proteins may serve as novel targets in FP-RMS. Here, we investigate the contribution of the epigenetic regulator BMI1 to FP-RMS. We examined RNA-seq tumor datasets and determined that BMI1 is robustly expressed in FP-RMS tumors, patient derived xenografts (PDXs), and cell lines. We depleted BMI1 using RNA interference and find that this leads to a marked decrease in cell growth. Next, we used two BMI1 inhibitors, PTC-209 and PTC-028, and showed that BMI1 inhibition decreases cell cycle progression and increases apoptosis in FP-RMS cell lines. In the in vivo setting, targeting BMI1 leads to decreased tumor growth. Mechanistically, we observe that BMI1 inhibition activates the tumor suppressive Hippo pathway. Collectively, these results identify BMI1 as a novel therapeutic vulnerability in FP-RMS and provide a foundation for further investigation of BMI1 in both FP-RMS and additional sarcoma histotypes.

cancer biology↗

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

Probing the Plasticity in the Active Site of Protein N-terminal Methyltransferase 1 Using Bisubstrate Analogs

The interactions of a series of bisubstrate analogs with protein N-terminal methyltransferase 1 (NTMT1) were examined to probe the molecular properties of the NTMT1 active site through biochemical characterization and structural studies. Our results indicate that a 2-C to 4-C atom linker enables its respective bisubstrate analog to occupy both substrate and cofactor binding sites of NTMT1, but the bisubstrate analog with a 5-C atom linker only interacts with the substrate binding site and functions as a substrate. Furthermore, the 4-C atom linker is the optimal and produces the most potent inhibitor (Ki, app = 130 {+/-} 40 pM) for NTMT1 to date, displaying over 100,000-fold selectivity over other methyltransferases and 3,000-fold even to its homolog NTMT2. This study reveals the molecular basis for the plasticity of the NTMT1 active site. Additionally, our study outlines a general guidance on the development of bisubstrate inhibitors for any methyltransferases.

biochemistry↗

bioRxiv2020

Selective Peptidomimetic Inhibitors of NTMT1/2: Rational design, synthesis, characterization, and crystallographic studies

Protein N-terminal methyltransferases (NTMTs) methylate the -N-terminal amines of proteins starting with the canonical X-P-K/R motif. Genetic studies imply that NTMT1 regulates cell mitosis and DNA damage repair. Herein, we report the rational design and development of the first potent peptidomimetic inhibitors for NTMT1. Biochemical and co-crystallization studies manifest that BM30 (IC50 of 0.89 {+/-} 0.10 {micro}M) is a competitive inhibitor to the peptide substrate and noncompetitive to the cofactor S-adenosylmethionine. BM30 exhibits over 100-fold selectivity to NTMT1/2 among a panel of 41 methyltransferases, indicating the potential to achieve high selectivity when targeting the peptide substrate binding site of NTMT1/2. Its cell-permeable analog DC432 (IC50 of 54 {+/-} 4 nM) decreases the N-terminal methylation level of SET protein in HCT116 cells. This proof-of principle study provides valuable probes for NTMT1/2 and highlights the opportunity to develop more cell-potent inhibitors to elucidate the function of NTMTs in future.

biochemistry↗

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

Comparative secretome of Magnaporthe oryzae identified proteins involved in virulence and cell wall integrity

Plant fungal pathogens secrete numerous proteins into the apoplast at the plant-fungus contact sites to facilitate colonization. Only a few secreted proteins were functionally characterized in Magnaporthe oryzae, the fungal pathogen causing rice blast disease worldwide. ALG3 is an -1, 3-mannosyltransferase function in N-glycan synthesis for secreted N-glycosylated proteins, and the {Delta}alg3 mutants show strong defects in cell wall integrity and fungal virulence, indicating a potential effect on the secretion of multiple proteins. In this study, we compared the secretome of wild type and {Delta}alg3 mutants, and identified 51 proteins that require ALG3 for proper secretion. These are predicted to be involved in metabolic processes, interspecies interactions, cell wall organization, and response to chemicals. The tested secreted proteins localized at the apoplast region surrounding the fungal infection hyphae. Moreover, the N-glycosylation of candidate proteins was significantly changed in the {Delta}alg3 mutant, leading to the reduction of protein secretion and abnormal protein localization. Furthermore, we tested the function of two genes, one is a previously reported M. oryzae gene Invertase 1 (INV1) encoding a secreted invertase, and the other one is a gene encoding an Acid mammalian chinitase (AMCase). The fungal virulence was significantly reduced and the cell wall integrity was altered in the {Delta}inv1 and {Delta}amcase mutant strains. Elucidation of the comparative secretome of M. oryzae improves our understanding of the proteins that require ALG3 for secretion, and of their function in fungal virulence and cell wall integrity.

plant biology↗

bioRxiv2020

Cell-ECM interactions play distinct and essential roles at multiple stages during the development of the aortic arch arteries

RationaleDefects in the morphogenesis of the 4th pharyngeal arch arteries (PAAs) give rise to lethal birth defects. Understanding genes and mechanisms regulating PAA formation will provide important insights into the etiology and treatments for congenital heart disease. ObjectiveCell-ECM interactions play essential roles in the morphogenesis of PAAs and their derivatives, the aortic arch artery (AAA) and its major branches; however, their specific functions are not well-understood. Previously, we demonstrated that integrin 5{beta}1 and fibronectin (Fn1) expressed in the Isl1 lineages regulate PAA formation. The objective of these studies was to investigate cellular mechanisms by which integrin 5{beta}1 and Fn1 regulate AAA morphogenesis. Methods and ResultsUsing temporal lineage tracing, whole-mount confocal imaging, and quantitative analysis of the second heart field (SHF) and endothelial cell (EC) dynamics, we show that the majority of PAA EC progenitors arise by E7.5 in the SHF and populate pharyngeal arch mesenchyme between E7.5 and E9.5. Consequently, SHF-derived ECs in the pharyngeal arches become organized into a uniform plexus of small blood vessels, which becomes remodeled into the PAAs between 31 - 35 somites. The remodeling of the vascular plexus is orchestrated by signals dependent on pharyngeal ECM microenvironment extrinsic to the endothelium. Conditional ablation of integrin 5{beta}1 or Fn1 in the Isl1 lineages showed that signaling by the ECM regulates AAA morphogenesis at multiple steps: 1) the recruitment of the SHF-derived ECs into the pharyngeal arches, 2) the remodeling of the uniform EC plexus in the 4th arches into the PAAs; and 3) differentiation of neural crest-derived cells abutting the PAA endothelium into vascular smooth muscle cells. ConclusionsPAA formation is a multi-step process entailing dynamic contribution of SHF-derived ECs to pharyngeal arches, the remodeling of endothelial plexus into the PAAs, and the remodeling of the PAAs into the AAA and its major branches. Cell-ECM interactions regulated by integrin 5{beta}1 and Fn1 play essential roles at each of these developmental stages.

developmental 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

LY6E Restricts the Entry of Human Coronaviruses, including the currently pandemic SARS-CoV-2

C3A is a sub-clone of human hepatoblastoma HepG2 cell line with the strong contact inhibition of growth. We fortuitously found that C3A was more susceptible to human coronavirus HCoV-OC43 infection than HepG2, which was attributed to the increased efficiency of virus entry into C3A cells. In an effort to search for the host cellular protein(s) mediating the differential susceptibility of the two cell lines to HCoV-OC43 infection, we found that ADAP2, GILT and LY6E, three cellular proteins with known activity of interfering virus entry, expressed at significantly higher levels in HepG2 cells. Functional analyses revealed that ectopic expression of LY6E, but not GILT or ADAP2, in HEK 293 cells inhibited the entry of HCoV-OC43. While overexpression of LY6E in C3A and A549 cells efficiently inhibited the infection of HCoV-OC43, knockdown of LY6E expression in HepG2 significantly increased its susceptibility to HCoV-OC43 infection. Moreover, we found that LY6E also efficiently restricted the entry mediated by the envelope spike proteins of other human coronaviruses, including the currently pandemic SARS-CoV-2. Interestingly, overexpression of serine protease TMPRSS2 or amphotericin treatment significantly neutralized the IFITM3 restriction of human coronavirus entry, but did not compromise the effect of LY6E on the entry of human coronaviruses. The work reported herein thus demonstrates that LY6E is a critical antiviral immune effector that controls CoV infection and pathogenesis via a distinct mechanism. ImportanceVirus entry into host cells is one of the key determinants of host range and cell tropism and is subjected to the control by host innate and adaptive immune responses. In the last decade, several interferon inducible cellular proteins, including IFITMs, GILT, ADAP2, 25CH and LY6E, had been identified to modulate the infectious entry of a variety of viruses. Particularly, LY6E was recently identified as host factors to facilitate the entry of several human pathogenic viruses, including human immunodeficiency virus, influenza A virus and yellow fever virus. Identification of LY6E as a potent restriction factor of coronaviruses expands the biological function of LY6E and sheds new light on the immunopathogenesis of human coronavirus infection.

microbiology↗

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

HELLO: A hybrid variant calling approach

Next Generation Sequencing (NGS) technologies that cost-effectively characterize genomic regions and identify sequence variations using short reads are the current standard for genome sequencing. However, calling small indels in low-complexity regions of the genome using NGS is challenging. Recent advances in Third Generation Sequencing (TGS) provide long reads, which call large-structural variants accurately. However, these reads have context-dependent indel errors in low-complexity regions, resulting in lower accuracy of small indel calls compared to NGS reads. When both small and large-structural variants need to be called, both NGS and TGS reads may be available. Integration of the two data types with unique error profiles could improve robustness of small variant calling in challenging cases. However, there isnt currently such a method integrating both types of data. We present a novel method that integrates NGS and TGS reads to call small variants. We leverage the Mixture of Experts paradigm which uses an ensemble of Deep Neural Networks (DNN), each processing a different data type to make predictions. We present improvements in our DNN design compared to previous work such as sequence processing using one-dimensional convolutions instead of image processing using two-dimensional convolutions and an algorithm to efficiently process sites with many variant candidates, which help us reduce computations. Using our method to integrate Illumina and PacBio reads, we find a reduction in the number of erroneous small variant calls of up to ~30%, compared to the state-of-the-art using only Illumina data. We also find improvements in calling small indels in low-complexity regions.

bioinformatics↗