Isolation and characterization of subunits from two distinct salmon gonadotropins.
Two distinct gonadotropins, GTH I and GTH II, isolated from female chum salmon pituitary glands, were separated into subunits by acid treatment and subsequent fractionation on reversed-phase high-performance liquid chromatography. GTH II was completely dissociated in 0.1% trifluoroacetic acid, while GTH I was partially dissociated. The acid-stable form of GTH I exhibited a potency identical to that of GTH I in stimulating estradiol-17 beta production in vitro. Both GTH I and GTH II consist of two dissimilar subunits. One subunit (alpha) is common to both GTHs, has Tyr as its N-terminal residue, and a molecular weight (Mr) of 22K by sodium dodecyl sulfate-polyacrylamide gel electrophoresis after reduction. The other subunit (beta) has a Mr of 17K and an N-terminal residue of Gly for GTH I, whereas GTH II beta is 18K and has an N-terminal residue of Ser, after reduction.
Suzuki
K
K
Laboratory of Molecular Endocrinology, School of Fisheries Sciences, Kitasato University, Iwate, Japan.
Kawauchi
H
H
Nagahama
Y
Y
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D004958:Estradiol / Q000378:metabolism; D005260:Female; D006023:Glycoproteins / Q000032:analysis; D006062:Gonadotropins / Q000032:analysis* / Q000502:physiology; D010902:Pituitary Gland / Q000032:analysis*; D012474:Salmon / Q000378:metabolism*
D000596:Amino Acids; D006023:Glycoproteins; D006062:Gonadotropins; D004958:Estradiol