RRC ID |
41934
|
Author |
Sugawara T, Shimizu H, Hoshi N, Nakajima A, Fujimoto S.
|
Title |
Steroidogenic acute regulatory protein-binding protein cloned by a yeast two-hybrid system.
|
Journal |
J Biol Chem
|
Abstract |
Steroidogenic acute regulatory (StAR) protein plays a key role in the transport of cholesterol from the outer mitochondrial membrane to the inner membrane. A StAR mutant protein lacking the first 62 amino acids (N-62 StAR protein) has been reported to be as effective as wild-type StAR protein. In the present study, we examined the mechanism by which StAR protein stimulates steroidogenesis. A Gal4-based yeast two-hybrid system was used to identify proteins interacting with N-62 StAR protein. Nine positive clones were obtained from screening 1 x 106 clones. The results of pull-down assays and mammalian two-hybrid assays confirmed interaction between N-62 StAR protein and the clone 4 translated product. The clone 4 translated product was named StAR-binding protein (SBP). We prepared an expression plasmid (pSBP) by inserting SBP cDNA into the pTarget vector. After cotransfection with the human cytochrome P450scc system, StAR expression vector, and pSBP, the amount of pregnenolone produced by COS-1 cells was increased. The amount of steroid hormones produced by steroidogenic cells subjected to small interfering RNA treatment was less than that produced by control cells. In conclusion, SBP binds StAR protein in cells and enhances the ability of StAR protein to promote syntheses of steroid hormones.
|
Volume |
278(43)
|
Pages |
42487-94
|
Published |
2003-10-24
|
DOI |
10.1074/jbc.M302291200
|
PII |
S0021-9258(20)82792-6
|
PMID |
12909641
|
MeSH |
Animals
COS Cells
Carrier Proteins / genetics
Carrier Proteins / isolation & purification*
Carrier Proteins / metabolism
Cholesterol Side-Chain Cleavage Enzyme / genetics
Cloning, Molecular*
Cricetinae
DNA, Complementary
Genetic Vectors
Humans
Male
Phosphoproteins / genetics
Phosphoproteins / isolation & purification
Phosphoproteins / metabolism*
Pregnenolone / analysis
Pregnenolone / biosynthesis*
Protein Binding
Steroids / analysis
Steroids / biosynthesis
Testis
Transfection
Two-Hybrid System Techniques
|
IF |
4.238
|
Times Cited |
19
|
WOS Category
|
BIOCHEMISTRY & MOLECULAR BIOLOGY
|
Resource |
Human and Animal Cells |
Y1(RCB0533)
COS-1(RCB0143)
Hep G2 |