A "20K" form of growth hormone in the murine pituitary gland.
Extracts of mouse and rat adenohypophyses have been analyzed for a low-molecular-weight variant of growth hormone (GH) known to occur in humans, the so-called "20K"-GH (mol wt = 20,000 vs 22,000 for traditional human GH). Pituitary proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunostained with an antiserum raised against murine GH. Reactive and unreactive bands in close vicinity of the major GH band were fingerprinted by a peptide-mapping technique that reveals only the tyrosine-containing peptides, but can be applied to fingerprint single protein bands within gels. We found a protein band 2000 mol wt smaller than the major murine GH in both mouse and rat pituitary glands whose fingerprint resembled that of major GH. The peptide-mapping results are consistent with the interpretation that the internal deletion of amino acid residues most likely is in the same region of the molecule as in the human 20K-GH. Unlike the human 20K-GH, however, the murine counterpart showed no cross-reactivity with an antiserum raised against 22K-GH in the test system used here.
D000595:Amino Acid Sequence; D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D013006:Growth Hormone / Q000032:analysis*; D006801:Humans; D007158:Immunologic Techniques; D008623:Mercaptoethanol / Q000494:pharmacology; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008970:Molecular Weight; D010903:Pituitary Gland, Anterior / Q000032:analysis*; D011388:Prolactin / Q000032:analysis; D051381:Rats; D013045:Species Specificity
D008623:Mercaptoethanol; D011388:Prolactin; D013006:Growth Hormone