Identification and characterization of the minimal promoter of Mipu1: the role of GC boxes in the regulation of basal transcription.
Mipu1, a novel gene encoding a KRAB/C2H2 zinc finger protein, was first reported to be up-regulated in myocardial ischemia-reperfusion injury, functioning to protect cells against oxidative stress. To map the promoter region of the gene and to understand its regulation, we identified the transcription start site and revealed that the 1366-bp fragment upstream of the transcription start site possesses promoter activity. Deletion constructs of the 5'-flanking region of Mipu1 lead to the identification of a minimal promoter, in which neither a TATA box nor a CAAT box was detected. Two GC boxes were found; however, they are the specific binding sites for Sp1-family transcription factors. Mutations in these GC boxes resulted in the total loss of Mipu1 minimal promoter activity. Finally, WP631, an Sp1-family-specific inhibitor, was found to decrease the promoter activity in a dose-dependent manner, indicating that the GC boxes are essential for the activity of the Mipu1 minimal promoter activity.
Lv
Ben
B
Department of Pathophysiology, Xiangya School of Medicine, Central South University, Changsha 410078, China.
Tang
Yiting
Y
Li
Xiayu
X
Wang
Guiliang
G
Yuan
Can
C
Liu
Ying
Y
Jiang
Lei
L
Xiao
Xianzhong
X
D024506:5' Flanking Region / Q000235:genetics; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics / Q000502:physiology; D002460:Cell Line; D003630:Daunorubicin / Q000031:analogs & derivatives / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation; D049410:Luciferases, Renilla / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics*; D016329:Sp1 Transcription Factor / Q000037:antagonists & inhibitors / Q000378:metabolism; D024363:Transcription Initiation Site; D014158:Transcription, Genetic / Q000187:drug effects; D014162:Transfection
C520710:Mipu1 protein, rat; D009687:Nuclear Proteins; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D016329:Sp1 Transcription Factor; C104426:WP 631; D049410:Luciferases, Renilla; D003630:Daunorubicin