Concomitant synthesis of beta-endorphin and alpha-melanotropin from two forms of pro-opiomelanocortin in the rat pars intermedia.
- 1 October 1979
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 76 (10) , 5085-5089
- https://doi.org/10.1073/pnas.76.10.5085
Abstract
In the pars intermedia of rat pituitary glands, 2 forms of a common precursor for corticotropin (ACTH) and .beta.-lipotropin with apparent MW of 34,000 and 36,000 were resolved by sodium dodecyl sulfate/acrylamide gradient slab gel electrophoresis. High-performance liquid chromatographic analysis of [35S]methionine-labeled tryptic fragments of the 2 forms of the precursor revealed that both contained copies of ACTH-(1-8) and .beta.-lipotropin-(61-69) sequences. When biosynthetic studies were performed in the presence of tunicamycin, the 34,000 and 36,000 dalton forms were replaced by a peptide with an apparent MW of 32,000. The 34,000 and 36,000 dalton forms of the precursor represent 2 glycoprotein variants of similar polypeptides, differing in the number of asparagine-linked carbohydrate moieties. During pulse-chase incubations with [35S]methionine, the precursor forms were cleaved into 2 major groups of labeled products: .beta.-endorphin and a mixture of ACTH fragments closely related to .alpha.-melanotropin. No ACTH-(1-39) was found at the end of a 2-h chase period, suggesting that ACTH is not a significant hormone product of the rat pars intermedia.This publication has 17 references indexed in Scilit:
- Nucleotide sequence of cloned cDNA for bovine corticotropin-β-lipotropin precursorNature, 1979
- The role of glycosylation on the biosynthesis, degradation, and secretion of the acth‐β‐lipotropin common precursor and its peptide productsFEBS Letters, 1978
- The ACTH ‘family tree’ of the rhesus monkey changes with developmentNature, 1978
- Biosynthesis of beta-endorphin from beta-lipotropin and a larger molecular weight precursor in rat pars intermedia.Proceedings of the National Academy of Sciences, 1978
- Steps involved in the processing of common precursor forms of adrenocorticotropin and endorphin in cultures of mouse pituitary cellsBiochemistry, 1978
- beta-Lipotropin is the major opioid-like peptide of human pituitary and rat pars distalis: lack of significant beta-endorphin.Proceedings of the National Academy of Sciences, 1978
- Existence of a common precursor to ACTH and endorphin in the anterior and intermediate lobes of the rat pituaitaryJournal of Supramolecular Structure, 1978
- Characterization of a common precursor to corticotropin and beta-lipotropin: identification of beta-lipotropin peptides and their arrangement relative to corticotropin in the precursor synthesized in a cell-free system.Proceedings of the National Academy of Sciences, 1977
- Characterization of a common precursor to corticotropin and beta-lipotropin: cell-free synthesis of the precursor and identification of corticotropin peptides in the molecule.Proceedings of the National Academy of Sciences, 1977
- STRUCTURE AND BIOSYNTHESIS OF PEPTIDES RELATED TO CORTICOTROPINS AND β‐MELANOTROPINSAnnals of the New York Academy of Sciences, 1977