Glucagon Synthesis with mRNA Preparation of a Glucagon-Producing Tumor (IT-1)

JUN'ICHI SATO
1989 Endocrinologia Japonica  
Nucleic acids were extracted from the tumor (1T-1) and punned to give poly (A)-containing RNA, which was subjected to protein synthesis in vitro with a wheat germ extract. Gel-filtration (Bio Gel P-30) profiles of the translated product showed the presence of glucagon-like substance, and the results of treatment of fractions with glucagon antibodies (30K or K4023) showed the possibility that translated products contained true-glucagon. This confirms glucagon synthesis in IT-1. The molecular
more » ... ht of the translated glucagon was estimated to be 3,000 from the K-value. The time courses of the glucagon synthesis were examined in cultured tumor cells (ITC-1) using 3H-leucine as a tracer . A large molecular weight protein was already detected after pulse labeling for 1 h. The amount of labeled glucagon in the cells was shown to be maximum at 1 h. True-glucagon was converted at 3 h to smaller molecular weight peptides which reacted with the C-terminal antibody of glucagon. In vitro protein synthesis, peptides with molecular weights of around 10,000 were major products in 15-30 min.
doi:10.1507/endocrj1954.36.755 pmid:2559841 fatcat:oo6pzpsrefdorijexgpmsjvn2i