Project description:To test the influence of IGF2BPs on the stability of their interacting mRNAs, as reported previously for some targets (Yisraeli, 2005), we simultaneously depleted all three IGF2BP family members using siRNAs and compared the cellular RNA from knockdown and mock-transfected cells on microarrays. The levels of transcripts identified by PAR-CLIP decreased in IGF2BP-depleted cells, indicating that IGF2BP proteins stabilize their target mRNAs. Moreover, transcripts that yielded clusters with the highest T to C mutation frequency were most destabilized (Figure 4G of PMID 20371350), indicating that the ranking criterion that we derived based on the analysis of PUM2 and QKI data generalizes to other RNA-binding proteins (RBPs). The RBPs IGF2BP1-3 were depleted by siRNAs and the expression level was compared to mock-transfected HEK 293 cells.
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:To test the influence of IGF2BPs on the stability of their interacting mRNAs, as reported previously for some targets (Yisraeli, 2005), we simultaneously depleted all three IGF2BP family members using siRNAs and compared the cellular RNA from knockdown and mock-transfected cells on microarrays. The levels of transcripts identified by PAR-CLIP decreased in IGF2BP-depleted cells, indicating that IGF2BP proteins stabilize their target mRNAs. Moreover, transcripts that yielded clusters with the highest T to C mutation frequency were most destabilized (Figure 4G of PMID 20371350), indicating that the ranking criterion that we derived based on the analysis of PUM2 and QKI data generalizes to other RNA-binding proteins (RBPs).
Project description:To evaluate the effect of IGF2BPs on mRNA stability and gene expression output, we conducted RNA-seq in individual IGF2BP knockdown and control HepG2 cells with or without actinomycin D treatment. Our RNA-seq and RNA stability profiling revealed that IGF2BPs were involved in RNA stability regulation and contributed to the stabilization of the transcriptome.
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.
