Project description:Through alternative processing of pre-mRNAs, individual mammalian genes often produce multiple mRNA and protein isoforms that may have related, distinct or even opposing functions. Here we report an in-depth analysis of 15 diverse human tissue and cell line transcriptomes based on deep sequencing of cDNA fragments, yielding a digital inventory of gene and mRNA isoform expression. Analysis of mappings of sequence reads to exon-exon junctions indicated that ~94% of human genes undergo alternative splicing (AS), ~86% with a minor isoform frequency of 15% or more. Differences in isoform-specific read densities indicated that a majority of AS and alternative cleavage and polyadenylation (APA) events exhibit variation between tissues. Variations in alternative mRNA isoform expression between 6 individuals were also detected in cerebellar cortex, with ~2- to 3-fold less isoform variation observed between individuals than between tissues. Extreme or 'switch-like' regulation of splicing between tissues was associated with increased sequence conservation and with generation of full-length open reading frames. Patterns of AS and APA were strongly correlated across tissues, suggesting coordinated regulation, and sequence conservation of known regulatory motifs in both regulated introns and 3' UTRs suggested common involvement of the same factors in regulation of tissue-specific splicing and polyadenylation. Exam mRNA expression in 15 human tissues and cell lines
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Through alternative processing of pre-mRNAs, individual mammalian genes often produce multiple mRNA and protein isoforms that may have related, distinct or even opposing functions. Here we report an in-depth analysis of 15 diverse human tissue and cell line transcriptomes based on deep sequencing of cDNA fragments, yielding a digital inventory of gene and mRNA isoform expression. Analysis of mappings of sequence reads to exon-exon junctions indicated that ~94% of human genes undergo alternative splicing (AS), ~86% with a minor isoform frequency of 15% or more. Differences in isoform-specific read densities indicated that a majority of AS and alternative cleavage and polyadenylation (APA) events exhibit variation between tissues. Variations in alternative mRNA isoform expression between 6 individuals were also detected in cerebellar cortex, with ~2- to 3-fold less isoform variation observed between individuals than between tissues. Extreme or 'switch-like' regulation of splicing between tissues was associated with increased sequence conservation and with generation of full-length open reading frames. Patterns of AS and APA were strongly correlated across tissues, suggesting coordinated regulation, and sequence conservation of known regulatory motifs in both regulated introns and 3' UTRs suggested common involvement of the same factors in regulation of tissue-specific splicing and polyadenylation.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:We have sequenced miRNA libraries from human embryonic, neural and foetal mesenchymal stem cells. We report that the majority of miRNA genes encode mature isomers that vary in size by one or more bases at the 3’ and/or 5’ end of the miRNA. Northern blotting for individual miRNAs showed that the proportions of isomiRs expressed by a single miRNA gene often differ between cell and tissue types. IsomiRs were readily co-immunoprecipitated with Argonaute proteins in vivo and were active in luciferase assays, indicating that they are functional. Bioinformatics analysis predicts substantial differences in targeting between miRNAs with minor 5’ differences and in support of this we report that a 5’ isomiR-9-1 gained the ability to inhibit the expression of DNMT3B and NCAM2 but lost the ability to inhibit CDH1 in vitro. This result was confirmed by the use of isomiR-specific sponges. Our analysis of the miRGator database indicates that a small percentage of human miRNA genes express isomiRs as the dominant transcript in certain cell types and analysis of miRBase shows that 5’ isomiRs have replaced canonical miRNAs many times during evolution. This strongly indicates that isomiRs are of functional importance and have contributed to the evolution of miRNA genes
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs. One-condition experment, gene expression of 3A6