Intercellular sugar levels influence rDNA silencing
Following the promising advances in epigenetic, a study from German Cancer Research Center reveals an association between deacetylation and the starvation of cellular glucose which suggest an epigenetic effect on the regulation of ribosomal RNA genes (rDNA) expression. What makes this finding interesting is that such correlation is occurring in a crucial process of eukaryotic cell proliferation, which is ribosomal RNA production.
rDNA expression is supposed to be regulated by both the active and inactive state of SNF2h-containing nucleolar chromatin remodelling complex (NoRC). Shifting rRNA genes to the transcriptional mode occurs by acetylating lysine (K633) at TIP5, which is the major protein in NoRC, bordering to RNA binding sites. Accordingly, this action affects the highly condensed chromatic structure (heterochromatin), nucleosomes positioning and rDNA silencing.
As a reversible action, deacetylation enzyme removes the acetyl group from the lysine (K633). Epigenetically, deacetylase is highly released with glucose starvation to strengthen non-coding RNA (pRNA) binding to its complement sequence in the gene. As a result, rRNA gene becomes silent.
By Yazeed ALDUHAYAN
rDNA expression is supposed to be regulated by both the active and inactive state of SNF2h-containing nucleolar chromatin remodelling complex (NoRC). Shifting rRNA genes to the transcriptional mode occurs by acetylating lysine (K633) at TIP5, which is the major protein in NoRC, bordering to RNA binding sites. Accordingly, this action affects the highly condensed chromatic structure (heterochromatin), nucleosomes positioning and rDNA silencing.
As a reversible action, deacetylation enzyme removes the acetyl group from the lysine (K633). Epigenetically, deacetylase is highly released with glucose starvation to strengthen non-coding RNA (pRNA) binding to its complement sequence in the gene. As a result, rRNA gene becomes silent.
By Yazeed ALDUHAYAN
0 Comments:
Post a Comment
<< Home