The 3'-untranslated region of apolipoprotein II mRNA contains two independent domains that bind distinct cytosolic factors.

摘要: The 3'-untranslated region of apolipoprotein II (apoII) mRNA contains target sites for breakdown (Binder, R., Hwang, S.-P. L., Ratnasabapathy, and Williams, D. L. (1989) J. Biol. Chem. 264, 16910-16918). Degradation occurs via endonucleolytic cleavage at 5'-AAU-3'/5'-UAA-3' elements in single-stranded loop domains the region. occur two clusters that are localized within larger secondary structure. In this study, gel shift label transfer assays were used to identify liver cytosolic factors recognize apoII mRNA. results show preferential binding as compared coding UV cross-linking experiments confirmed labeled by a subset proteins entire Two distinct identified upstream domain encompassing nucleotides 400-547 extends from translation stop codon through complex stem-loop D structure described previously. This primarily 34-kDa protein experiments. downstream 568-643 includes another terminates universal polyadenylation signal. 60-kDa did not compete with each other or These indicate can form independent messenger ribonucleoprotein complexes include degradation. We speculate these may play role degradation regulation process.