The in vitro synthesized and processed human insulin receptor precursor binds insulin.
The cell-free examination of the human insulin receptor during biogenesis may provide a greater understanding of the elements that contribute to the acquisition of receptor function. The insulin receptor precursor components were produced in a cell-free system and the insulin binding ability of the [35S]methionine-labeled translation products was determined. The processed proreceptor represented by a 190 kDa band was retained on insulin-linked biotin-streptavidin agarose or an insulin column. The insulin binding 190 kDa band migrated slower than the non-binding 190 kDa band on SDS-PAGE which suggests that covalent modifications account for these differences. The trypsin-digested product of the 190 kDa proreceptor was also retained on insulin-linked biotin-streptavidin agarose, however the alpha-subunit precursor was retained on insulin agarose to a much lesser degree. We conclude that a significant fraction of the processed, in vitro translated insulin proreceptor acquires insulin binding ability.
Tsuda
S
S
Department of Medicine, John A. Burns School of Medicine, University of Hawaii-Manoa, Honolulu 96813, USA.
Kaihara
M
M
Zhou
X
X
Britos
D
D
Arakaki
R
R
D000818:Animals; D002474:Cell-Free System; D002478:Cells, Cultured; D002846:Chromatography, Affinity; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D037102:Lectins / Q000378:metabolism; D008024:Ligands; D008565:Membrane Proteins / Q000378:metabolism; D010447:Peptide Hydrolases / Q000378:metabolism; D011485:Protein Binding; D014176:Protein Biosynthesis; D011498:Protein Precursors / Q000235:genetics / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D011972:Receptor, Insulin / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism*; D012156:Reticulocytes / Q000378:metabolism; D014158:Transcription, Genetic; D014357:Trypsin / Q000494:pharmacology; D014981:Xenopus / Q000196:embryology
D007328:Insulin; D037102:Lectins; D008024:Ligands; D008565:Membrane Proteins; D011498:Protein Precursors; D011994:Recombinant Proteins; C051512:insulin proreceptor; D011972:Receptor, Insulin; D010447:Peptide Hydrolases; D014357:Trypsin