Rat inhibin: molecular cloning of alpha- and beta-subunit complementary deoxyribonucleic acids and expression in the ovary.
Inhibin is a gonadal protein hormone that suppresses the secretion of FSH from pituitary gonadotrophs. It has previously been characterized as a heterodimer of two dissimilar subunits (alpha, 18 kilodaltons and beta, 14 kilodaltons) the smaller of which exists in two forms (beta A and beta B) and can form dimers that stimulate the secretion of FSH. In the present work, cDNA clones encoding the inhibin alpha- and beta A-subunits have been isolated from rat ovary and characterized. The alpha-inhibin cDNA predicts a precursor protein of 366 amino acids containing the 133 amino acid mature alpha-subunit at its COOH-terminus. The beta A-inhibin cDNA predicts a precursor protein of 424 amino acids containing the 116 amino acid beta A-subunit at its COOH-terminus. Analysis of rat ovarian RNA indicates that alpha-inhibin mRNA levels are stimulated by PMSG treatment in vivo. In cultured granulosa cells, FSH also stimulates alpha-inhibin mRNA, and the FSH effect is suppressed by cotreatment with GnRH. Hybridization in situ to rat ovarian tissue demonstrates that both the alpha-inhibin and beta A-inhibin mRNAs are specifically expressed in granulosa cells of the developing follicles.
Woodruff
T K
TK
Department of Biochemistry, Molecular Biology and Cell Biology, Northwestern University, Evanston, Illinois 60201.
Meunier
H
H
Jones
P B
PB
Hsueh
A J
AJ
Mayo
K E
KE
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002478:Cells, Cultured; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D005260:Female; D006107:Granulosa Cells / Q000378:metabolism*; D007265:Inhibins / Q000235:genetics*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D011919:Rats, Inbred Strains
D010446:Peptide Fragments; D012333:RNA, Messenger; D007265:Inhibins; D004247:DNA