Open AccessRegulation ofin vitrotranslation by double-stranded RNA in mammalian cell mRNA preparations
Author(s) -
Gerg Pratt,
Angela R. Galpine,
Nigel A. Sharp,
Susan Palmer,
Michael J. Clemens
Publication year - 1988
Publication title -
nucleic acids research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 9.008
H-Index - 537
eISSN - 1362-4954
pISSN - 0305-1048
DOI - 10.1093/nar/16.8.3497
Subject(s) - reticulocyte , biology , rna , messenger rna , lysis , protein biosynthesis , five prime cap , microbiology and biotechnology , nuclease , translation (biology) , biochemistry , polyadenylation , globin , non coding rna , dna , gene
Polyadenylated mRNA has been purified from a variety of human and mouse cell sources. These preparations are actively translated in the wheat germ cell-free system but have only poor ability to stimulate the nuclease-treated reticulocyte lysate. The translation of endogenous and exogenous globin mRNA is strongly inhibited by the poly(A)+ RNA preparations in reticulocyte lysates. Both polysomal and non-polysomal RNA have similar effects but poly(A)+ RNA is almost 2000-fold more inhibitory than poly(A)-RNA on a weight basis. The inhibition is abolished in the presence a high concentration of poly(I).poly(C). Analysis of endogenous eIF-2 in the lysate reveals that the subunit becomes extensively phosphorylated in the presence of the inhibitory poly(A)+ RNA. Prolonged incubation of lysate with poly(A)+ RNA also causes some nucleolytic degradation of polysomal globin mRNA. These characteristics suggest that some eukaryotic cell mRNAs contain regions of double-stranded structure which are sufficiently extensive to activate translational control mechanisms in the reticulocyte lysate.