Isolation and characterization of beta-endorphin-(1-9) from human and rat pituitaries.
Using a radioimmunoassay specific for the carboxyl terminus of beta-endorphin-(1-9) large amounts of beta-endorphin-(1-9)-immunoreactive material was detected in the human pituitary. The major peak of immunoreactivity was purified and characterized by fast atom bombardment-mass spectrometry and Edman degradation sequencing as authentic beta-endorphin-(1-9). In the rat pituitary the highest concentration of beta-endorphin-(1-9) immunoreactivity was in the posterior neurointermediate lobe. This material was identified as N-acetyl beta-endorphin-(1-9) by multiple radioimmunoassays, gel chromatography, and reversed-phase high-performance liquid chromatography. Control experiments determined that beta-endorphin-(1-9) was not formed postmortem or during the extraction procedure. These studies suggest that single lysine residues, similar to single arginine residues, are potential sites of posttranslational processing.
Roth
K A
KA
Department of Pathology, Washington University School of Medicine, St. Louis, MO 63110.
Unanue
R A
RA
Leykam
J
J
Tyler
A N
AN
D000328:Adult; D000818:Animals; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D013058:Mass Spectrometry; D010902:Pituitary Gland / Q000032:analysis*; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains