3' flanking region: A region of DNA which is not copied into the mature mRNA, but which is present adjacent to 3' end of the gene. It was originally thought that the 3' flanking DNA was not transcribed at all, but it was discovered to be transcribed into RNA, but quickly removed during processing of the primary transcript to form the mature mRNA. The 3' flanking region often contains sequences which affect the formation of the 3' end of the message. It may also contain enhancers or other sites to which proteins may bind.
谢谢版主解答。看了几篇文献,找了两个针对 “It may also contain enhancers or other sites to which proteins may bind.”的例子,增强与抑制各一例,供大家参考。
一个是EPO基因,在其polyA位点下游120bp处的一段150bp的片断具有增强子的作用,并且是位置和方向依赖性的,在缺氧的条件下,这一片段能够使EPO基因的表达升高15倍。( JBC, Volumn 266: 15563-15566)
一个是人生长激素基因,在其3‘侧翼区(polyA下游大约100多bp处)存在一段起沉默作用的Alu重复片段,可抑制hGH的表达。(Molecular Endocrinology 20: 2559-2575)