Combination of rat lutropin subunits occurs early in the secretory pathway.
Open Access
- 1 December 1982
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 79 (24) , 7649-7653
- https://doi.org/10.1073/pnas.79.24.7649
Abstract
The combination of lutropin (LH; luteinizing hormone) .alpha. and .beta. subunits was examined in rat pituitaries incubated with [35S]methionine or [35S]sulfate. Combination was assessed by using antiserum directed against the .beta. subunit. Combination of most of the subunits proceeds rapidly, well before the addition of sulfate and prior to the processing of asparagine-linked oligosaccharides to the complex form. Combination appears to initiate in the endoplasmic reticulum and does not require those post-translational modifications. Two forms of the LH-.alpha. subunit were processed, one that is secreted into the medium not associated with the LH .beta. subunit and another secreted as part of the .alpha.-.beta. dimer. Both forms of the .alpha. subunit are sulfated, and subsequent to sulfate addition, secretion of free .alpha. subunit and the dimer apparently occurs independently by separate pathways.This publication has 20 references indexed in Scilit:
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