Vaibhav D. Bhatt

Isolation and characterization of H9N2 influenza virus isolates from poultry respiratory disease outbreak

The present study reports isolation and characterization of H9N2 virus responsible for disease characterized by symptoms including difficulty in respiration, head swelling, nasal discharge, reduced feed intake, cyanotic comb, reduced egg production and mortality. Virus isolation from allantoic fluid inoculated with tracheal aspirates and whole genome sequencing of two isolates were performed on an Ion-Torrent sequencer. Phylogenetic analysis revealed that the two H9N2 isolates are reassortant viruses showing a G1-like lineage for HA, NA and NP, a Hok/49/98-like lineage for PB1 and PA, PK/UDL-01/05-like lineage for PB2, IL/90658/00-like lineage for NS and an unknown lineage for M gene. Analyses of the HA cleavage site showed a sequence of (333PARSSR↓GL340) indicating that these isolates are of low pathogenicity. Isolate 2 has leucine at amino acid position 226, a substitution which is associated with mammalian adaptation of avian influenza virus. Isolate 1 has the S31N substitution in the M2 gene that has been associated with drug resistance as well as R57Q and C241Y mutations in the NP gene which are associated with human adaptation. The result reported here gives deep insight in to H9N2 viruses circulating in domestic poultry of India and supports the policy of active efforts to control and manage H9N2 infections in Indian poultry.

Genome Sequence of Pasteurella multocida subsp. gallicida Anand1_poultry

We report the finished and annotated genome sequence of Pasteurella multocida gallicida strain Anand1_poultry, which was isolated from the liver of a diseased adult female chicken. The strain causes a disease called fowl cholera, which is a contagious disease in birds. We compared it with the published genome sequence of Pasteurella multocida Pm70.

Identification of novel transcripts deregulated in buccal cancer by RNA-seq

The differential transcriptome analysis provides better understanding of molecular pathways leading to cancer, which in turn allows designing the effective strategies for diagnosis, therapeutic intervention and prediction of therapeutic outcome. This study describes the transcriptome analysis of buccal cancer and normal tissue by CLC Genomics Workbench from the data generated by Roches 454 sequencing platform, which identified total of 1797 and 2655 genes uniquely expressed in normal and cancer tissues, respectively with 2466 genes expressed in both tissues. Among the genes expressed in both tissues, 1842 were up-regulated whereas 624 were down-regulated in cancer tissue. Besides transcripts known to be involved in cancer, this study led to the identification of novel transcripts, with significantly altered expression in buccal cancer tissue, providing potential targets for diagnosis and cancer therapeutics. The functional categorization by the KEGG pathway and gene ontology analysis revealed enrichment of differentially expressed transcripts to various pathways leading to cancer, including the p53 signaling pathway. Moreover, the gene ontology analysis unfolded suppression of transcripts involved in actin mediated cell contraction process. The down-regulation of four of these transcripts MYL1, ACTA1, TCAP and DESMIN in buccal cancer were further supported by quantitative PCR signifying its possible implication in the cancer progression.

Metagenomic analysis of buffalo rumen microbiome: Effect of roughage diet on Dormancy and Sporulation genes.

Buffalo rumen microbiome experiences a variety of diet stress and represents reservoir of Dormancy and Sporulation genes. However, the information on genomic responses to such conditions is very limited. The Ion Torrent PGM next generation sequencing technology was used to characterize general microbial diversity and the repertoire of microbial genes present, including genes associated with Dormancy and Sporulation in Mehsani buffalo rumen metagenome. The research findings revealed the abundance of bacteria at the domain level and presence of Dormancy and Sporulation genes which were predominantly associated with the Clostridia and Bacilli taxa belonging to the phyla Firmicutes. Genes associated with Sporulation cluster and Sporulation orphans were increased from 50% to 100% roughage treatment, thereby promoting sporulation all along the treatments. The spore germination is observed to be the highest in the 75% roughage treatment both in the liquid and solid rumen fraction samples with respect to the decrease in the values of the genes associated with spore core dehydration, thereby facilitating spore core hydration which is necessary for spore germination.

RNA-Seq reveals differentially expressed isoforms and novel splice variants in buccal mucosal cancer.

Buccal mucosal cancer (BMC) is a multifactorial disease with poorly defined genetic profile and prognosis due to late detection stage and unavailability of reliable prognostic markers. To identify aberrant transcriptional events, we employed high throughput RNA-Seq analysis of BMC and normal tissue. Comparative transcriptome analysis with Cufflinks revealed 260 up and 328 down regulated genes whereas, 350 up and 397 down regulated isoforms by at least two folds over buccal normal in BMC. Study revealed 46 splice variants in normal and 106 in cancer, out of which 10 variants were validated with end point RT-PCR. Expression of two isoforms of CD74 was validated using RT-qPCR and found in accordance with RNA-Seq. Further extensive follow up analysis of modulator genes, isoforms and splice variants found in this study, might be useful in deep understanding of pathological changes in BMC and development of prospective intervention strategies.

Transcriptomic dissection of myogenic differentiation signature in caprine by RNA-Seq.

Muscle growth and development from the embryonic to the adult stage of an organism consists of a series of exquisitely regulated and orchestrated changes in expression of genes leading to muscle maturation. In this study, we performed whole transcriptome profiling of adult caprine skeletal muscle derived myoblast and fused myotubes. Using Ion Torrent PGM sequencing platform, a total of 948,776 and 799,976 reads were generated in myoblasts and fused myotubes, respectively. The sequence reads were analyzed on CLC Genomics Workbench using Bos taurus RNA database to study the gene expression in both stages to study different genes responsible for muscle development and regeneration. The up and down-regulated genes were analyzed for gene ontology (GO) and KEGG pathways by Database for Annotation, Visualization and Integrated Discovery (DAVID) database. We found many genes exclusive to multinuclear fused myotubes and contractile nature of skeletal muscle, whereas up-regulated genes in myoblast stage were related to cell division and transcriptional regulation. Out of 27 genes selected for expression validation by RT-qPCR (reverse transcriptase-quantitative polymerase chain reaction), 19 genes showed the expression pattern comparable with CLC Genomics Workbench findings. Further, mRNA originated muscle specific microRNAs (miRNA-1 and miRNA-133b) were also observed in the fused myotubes along with other miRNAs with possible importance in muscle development. This study highlights important genes responsible for muscle development and differentiation in adult skeletal muscle system.

The landscape of alternative splicing in buccal mucosa squamous cell carcinoma.

OBJECTIVESnAlternative splicing (AS) is a key regulatory mechanism in the process of protein synthesis generating transcriptome and proteome diversity. In this study, we attempted to identify alternative splicing in a pair of BMSCC cancer and adjacent normal tissue using RNAseq datasets and also assessed the potential of these datasets to provide quantitative measurements for alternative splicing levels.nnnMATERIALS AND METHODSnWe performed high-throughput sequencing of buccal mucosal cancer and healthy tissue cDNA library which resulted in a transcriptome map of BMSCC cancer. RNAseq analysis was performed to assess alternative splicing complexity in cancer tissue and to search splice junction sequences that represent candidate new splicing events. The splice junctions were predicted by SpliceMap software and putative assembled transcripts validated using the RT-PCR. We also analyzed the coding potential of alternative spliced candidate by HMMER.nnnRESULTSnWe detected a total of 11 novel splice junctions derived mostly from alternate 5 splice site; including two of them which contained new translation initiation sites (TISs). We have identified novel IgG pseudogene and a fusion transcript of MEMO1 and RPS9, which were further confirmed by PCR from genomic DNA. We also found novel putative long non-coding RNA (lncRNA), which is antisense to SPINK5 gene. The coding potential of these AS variants revealed that alternative splicing caused premature termination, insertion/deletion of amino acid (s) or formation of novel N-terminus.nnnCONCLUSIONSnDifferential splicing of these novel AS variants between cancer and adjacent normal tissue suggests their involvement in BMSCC cancer development and progression.

Transcriptome analysis and SNP Identification in SCC of Horn in (Bos indicus) Indian cattle

Single Nucleotide Polymorphisms (SNPs) have become the marker of choice for genome wide association studies. In order to provide the best genome coverage for the analysis of disease, production and performance traits, a large number of relatively evenly distributed SNPs are needed. The main objective of present work was to identify large numbers of gene-associated SNPs using high-throughput sequencing in squamous cell carcinoma of horn. RNA-seq analysis was conducted on 2 tissues viz. Horn Cancer (HC) and Horn Normal (HN) in Kankrej breed of cattle. A total of 909,362 reads with average read length of 405 bp for HC and 583,491 reads with average read length of 411 bp for HN were obtained. We found 9532 and 7065 SNPs as well as 1771 and 1172 Indels in HC and HN, respectively, from which, 7889 SNPs and 1736 Indels were uniquely present in HC, 5886 SNPs and 1146 Indels were uniquely present in HN and reported first time in Bos indicus, whereas the rest are already reported in Bos taurus dbSNP database. The gene-associated SNPs and Indels were high in upregulated genes of HC as compared to HN. Analysis of differentially expressed genes was identified, these genes are involved in regulation of cell proliferation, apoptosis, gene transcription, cell survival and metabolism through various metabolic pathways. The result of transcriptome expression profiling was validated using Real Time quantitative PCR in nine randomly selected genes. We identified numbers aberrant signaling pathways responsible for carcinogenesis in HC which are also commonly altered in squamous cell carcinoma (SCC) of lung in human being. We conclude that a large number of altered genes and dysfunction of multiple pathways are involved in the development of Horn Cancer. The present findings contribute to theoretical information for further screening of genes and identification of markers for early diagnosis of HC as well as SNPs identified in this report provide a much needed resource for genetic studies in B. indicus and shall contribute to the development of a high density SNP array. Validation and testing of these SNPs using SNP arrays will form the material basis for gene associated SNPs in HC.

A preliminary sketch of horn cancer transcriptome in Indian zebu cattle

Horn cancer, a type of squamous cell carcinoma, in zebu cattle is an expensive affair in Indian agriculture sector, which accounts for 83.34% of total tumors found. In general, cancer tissue confirms considerably different expression patterns when compared to a normal stage. This includes not only up/down regulation, but also, the aberrant gene expression, the presence of different non-coding RNAs (ncRNAs), pseudogenes expression and genes involved in unusual pathways. We employed Roche 454 next generation sequencing platform to sequence Bos indicus cancerous and normal horn tissue transcripts. This resulted into a total of 909,345 high-confidence deep sequencing reads and detected a range of unusual transcriptional events including tumor associated genes. We also validated expression of two of the four tested genes in five other similar tissue samples by RT-qPCR. Further, seven cancer specific non-coding transcripts were accessed and a few of them have been suggested as cancer specific markers. This study for the first time provides primary transcriptome sketch of Bos indicus horn cancer tissue, and also demonstrates the suitability of the 454 sequencer for transcriptome analysis, which supports the concept of varied gene expression in cancerous condition.

Comprehensive transcriptome profiling of squamous cell carcinoma of horn in Bos indicus.

Squamous cell carcinoma (SCC) of horn is frequently observed in Bos indicus affecting 1% of cattle population and accounting 83.34% of total tumours found. The transcriptome profile of horn cancer (HC) tissue and the matched normal (HN) tissue were analysed by RNA-seq using Roche 454 sequencing. A total of 1u2009504u2009900 reads comprising of 612 MB data were used to identify differentially expressed genes using CLC Genomic Workbench. These include up-regulation of KRT6A, KRT6B, KRT6C, KRT14, SFN, KRT84, PI3, COL17A1, ANLN, SERPINB5 and down-regulation of BOLA, SCGB1A1, CXCL17, KRT19, BPIFB1, NR4A1 and TFF3 in HC, which are involved in regulation of gene transcription, cell proliferation, apoptosis, cell survival and metabolic pathways. The qPCR analysis of several targets suggested concordance of gene expression profile with RNA-seq analysis. The present findings would provide basis for further screening of genes and identification of markers for early diagnosis and therapeutic intervention of HC.