The rat enhancer of split- and hairy-related protein-2 gene: hepatic expression, genomic structure, and promoter analysis.
The rat enhancer of split- and hairy-related protein-2 (SHARP-2) is a basic helix-loop-helix transcription factor. The hepatic expression of SHARP-2 mRNA was investigated under various conditions. The level was decreased in the regenerating rat liver and malignant hepatoma cells. In contrast, the expression of SHARP-2 mRNA was induced in rat livers by feeding a high-carbohydrate diet. To analyze the molecular mechanism involved in the regulation of the rat SHARP-2 gene expression, the gene was cloned. It was approximately 6-kb in length and consists of five exons and four introns. To investigate the transcriptional regulatory region of this gene, SHARP-2/firefly luciferase reporter plasmids were transfected into hepatoma cells. A functional analysis of 5(')-deletion constructs revealed that two E box sequences between -160 and -144 are mainly responsible for promoter activity. Although upstream stimulatory factors (USFs) bound to the element in vitro, USF2 failed to stimulate promoter activity from the element using the co-transfection experiment. Therefore, other E box-binding transcription factors differing from USF proteins or USF-associated proteins are necessary for transcriptional stimulation of the rat SHARP-2 gene.
Hirano
Satoko
S
Department of Pediatrics, Fukui Medical University, 910-1193 Fukui, Japan.
Yamada
Kazuya
K
Kawata
Hiroko
H
Shou
Zhangfei
Z
Mizutani
Tetsuya
T
Shigematsu
Yousuke
Y
Mayumi
Mitsufumi
M
Miyamoto
Kaoru
K
D000818:Animals; D001483:Base Sequence; D051792:Basic Helix-Loop-Helix Proteins; D045744:Cell Line, Tumor; D004268:DNA-Binding Proteins; D040461:Gene Components / Q000235:genetics; D017353:Gene Deletion; D005786:Gene Expression Regulation; D005796:Genes / Q000235:genetics*; D022781:Hepatocytes / Q000378:metabolism; D018398:Homeodomain Proteins / Q000096:biosynthesis* / Q000235:genetics* / Q000378:metabolism; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D009841:Oligonucleotides / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic; D051720:Upstream Stimulatory Factors
D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D008156:Luciferases; D009841:Oligonucleotides; D012333:RNA, Messenger; D014157:Transcription Factors; D051720:Upstream Stimulatory Factors; C491538:Bhlhe40 protein, rat; C497182:Usf1 protein, rat; C497187:Usf2 protein, rat