The proximal GC-rich region of p16(INK4a) gene promoter plays a role in its transcriptional regulation.
p16(INK4a) plays a key role in control of cell cycle progression by negatively regulating the CDK4/6 activity. This study establishes that the p16(INK4a) minimal promoter region required for the transcription factor Sp1 function is mapped at 62 bp upstream of the translation initiation codon. This region is GC-rich and shown to interact specifically with Sp1. siRNA-induced Sp1 silencing resulted in the inhibition of the p16(INK4a) minimal promoter activity. Additionally, by using a promoter sequence-directed siRNA method, we demonstrate that the histone H3 at the GC-rich region in the minimal promoter of p16(INK4a) is hypermethylated, with a concurrent reduction of both the activity of p16(INK4a) promoter and the level of endogenous p16(INK4a) mRNA. Moreover, we show that the specific mutation of the GC-rich region of the minimal promoter resulted in the complete loss of its regulatory activities. We conclude that the region spanning -62 to +1 bp of p16(INK4a) promoter plays a role in p16(INK4a) transcription regulation.
Wang
Xiuli
X
Institute of Genetics and Cytology, Northeast Normal University, Changchun, PR China.
Feng
Yunpeng
Y
Pan
Lina
L
Wang
Yanle
Y
Xu
Xin
X
Lu
Jun
J
Huang
Baiqu
B
D000818:Animals; D002460:Cell Line; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics* / Q000378:metabolism; D020862:GC Rich Sequence; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D006657:Histones / Q000378:metabolism; D006801:Humans; D008745:Methylation; D011401:Promoter Regions, Genetic; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D016329:Sp1 Transcription Factor / Q000378:metabolism; D014158:Transcription, Genetic
D019941:Cyclin-Dependent Kinase Inhibitor p16; D006657:Histones; D034741:RNA, Small Interfering; D016329:Sp1 Transcription Factor