How adjacent or remote CpG affects expression? - (Mar/25/2009 )
I got one conceptual question.
If the CpG island is not overlapping with Promoter region, But if it is adjacent to the promoter, then how does it affect gene expression? By binding to some proteins?
If CpG island is remote, then does it matter?
Reference to any paper will be appreciated. I am alos looking into.
If the CpG island is not overlapping with Promoter region, it is very likely the CpG region actually harbors the promoter sequence or alternative promoter. If you lax the criteria for the CpG island a bit, probably the island will extend into the known promoter. I would say CpG island is very indicative of promoter.
Methylated CpG islands can also recruit chromatin remodelling proteins. These islands probably do not have to be in the promoter region to have an effect.
ston on Apr 1 2009, 09:49 AM said:
thanks to all of you,
But i could not find out any paper where they mentioned explicitly how the CpG island which is remote from promoter is affecting.
Got one paper where they said short sequence of CG residues in promoter can act with remote CpG island. But how they did not mention.
H19/IGF are the prime examples of this and the binding of CTCF in a methylation dependent manner, this binding region is a CpG island and it can effect the expression of a gene remote from it.
methylnick on Apr 2 2009, 02:54 PM said:
thanks Nick, it was really helpful to find out the answer of my question.