Thus, hyperacetylated histones are generally associated with transcriptional permissiveness whereas hypoacetylated histones mediate gene repression.
Indirectly, it can facilitate the binding to methylated DNA of methyl-CpG-binding domain proteins, which can mediate gene repression through interaction with histone-modifying enzymes [ 28].
While FoxO could mediate gene repression through direct binding to gene promoters, as has been documented previously [ 54– 56], FoxO may also regulate gene repression through indirect mechanisms.
Indeed, it has recently been reported that short RNAs (50 200 nt), transcribed from repressed loci by stalled RNA polymerase II, interact with the PRC2 complex through their stem loop secondary structure and mediate gene repression through epigenetic modification [ 41].
MicroRNAs (miRNAs), the 20 22 nt long posttranscriptional regulators, mediate gene repression primarily by inducing translational repression or degradation of target mRNAs to affect almost all physiological processes including metabolic processes in higher eukaryotes (Filipowicz et al., 2008; Krützfeldt and Stoffel, 2006).
DNA methylation promotes gene silencing either by directly blocking the binding of transcription factors to DNA or by the binding of MBPs (methyl-binding proteins, e.g., MBD1, MBD2, MBD3, and MBD4), which can mediate gene repression through interaction with a co-repressor complex [ 18, 28].
The SMRT (Silencing Mediator of Retinoid and Thyroid hormone receptors) corepressor mediates gene repression by nuclear receptors and other transcriptional factors.
Together these observations suggest that some polycomb repressed sites rely more specifically on KDM2B mediated RING1B occupancy for normal H2AK119ub1 and polycomb mediated gene repression (Endoh et al., 2012).
Casciello, F. et al. G9a drives hypoxia-mediated gene repression for breast cancer cell survival and tumorigenesis.
Mechanisms by which interferon (IFN -γ actIFN -γ genes to promote mactivates activation are well studied, but little is known about mechanisms and functions of IFN-γ-mediated genesrepression.
This strongly suggests that HDAC-mediated gene repression is involved in the transcriptional function of NKX2.2 in Ewing's sarcoma.
