The HELP3 Subunit Of The Elongator Complex Regulates The Transcription Of Hsp70-2 Gene In Human Cells

The antisense oligonucleotides (AODN)are synthesized DNAs that can specifically bind to the mRNA or the DNA to block the gene expression. The antisense oligonucleotides can target the specific sequences of DNA double helix on the basis of base complement to form triple helix DNA resulting in the inhibition of the specific gene expression both at the transcriptional initiation and transcriptional elongation levels. The antisense oligonucleotide has become a hot spot in the treatments of cancer in recent years.The human Elongator complex is remarkably similar to its yeast counterpart in several aspects. In a previous study, we analyzed the functions of the hELP3 subunit of the human Elongator by using an in vivo yeast complementation system. However, direct evidence for hELP3 functions in regulating gene expression in human cells had not been obtained. In this study, we used the hELP3 antisense oligonucleotide inhibitors to knock down the hELP3 gene expression to investigate its functions in human 293T cells. The results showed that reduction of hELP3 protein caused a significant suppression of hsp70-2 gene expression, and this was accompanied by histone H3 hypoacetylation and a decreased RNAPII density at hsp70-2 gene. Moreover, the data also demonstrated that hELP3 exerted the transcriptional regulatory function directly through its presence at the hsp70-2 gene. Data presented in this thesis provide further insight into and direct evidence of the functions of hELP3 in hsp70-2 gene transcriptional elongation in human cells.