The N-terminal peptide of the inhibin alpha subunit What are its endocrine and paracrine roles?
alphaN inhibin (molecular mass 23 24 kD) is present in the pro-alphaN-alphaC subunit of inhibin and can be released by cleavage at the flanking arginine residues during posttranslational processing. Although the alphaN protein isolated from bovine follicular fluid has no inhibinlike (FSH suppressing) activity, alphaN is present in high molecular weight forms of biologically active inhibin found in follicular fluid and plasma. alphaN may modify the biological activity of inhibin by influencing its half-life or access to its receptor. alphaN may also play a role in regulating fertility through a local action on ovulation by the ovary that is independent of the actions of inhibin. The evidence suggests a unique physiological significance for the precursor peptides of the inhibin-alpha subunit in both the endocrine and paracrine control of fertility.
Russell
D L
DL
Department of Cell Biology, Baylor College of Medicine, Houston, TX 77030, USA.
Findlay
J K
JK