Abstract
Poly(A)-containing mRNA has been prepared from the polyribosomes and post-polyribosomal mRNP fraction of duck reticulocytes. The coding capacity of the respective mRNA populations has been examined by translation in vitro followed by two-dimensional electrophoresis of the 35S-labeled polypeptides. A detailed analysis of these results is given elsewhere (Imaizumi-Scherrer, M.-T., Maundrell, K., Civelli, O., and Scherrer, K. (1982) Dev. Biol. 93, 126-138). Here, we focus on one of these translation products which migrates as a slightly basic protein of 73,000 molecular weight. By two-dimensional electrophoretic analysis and partial peptide mapping, we show that this protein is indistinguishable from the poly(A)-binding protein. We conclude that the majority of the coding sequences for this protein are translationally repressed in the reticulocyte cytoplasm.
Highlights
Poly(A)-containing mRNA has been prepared from the polyribosomes and post-polyribosommaRl NP fraction of duck reticulocytes
By 32,000 rpm for 2 h and the gradient was pooled into polyribosomes two-dimensionalelectrophoretic analysis andpartial and postpolyribosomal mRNP particleson the basis of AZwprofies peptide mapping, we show thatthis protein is indistin- andproteincomposition of selectedfractions.Poly(A)-containing guishable from the poly(A)-binding protein
Preparations of deproteinized mRNA isolated fromthe polyribosomal and postpolyribosomal subfractions of duck reticulocytecytoplasm showcomparabletemplateactivity when translated in vitro in a nuclease-treated rabbit reticulocyte lysate.The ”S-labeled translationproducts of the respective mRNA populations separated by two-dimensional electrophoresis areshownin Fig. 1
Summary
Poly(A)-containing mRNA has been prepared from the polyribosomes and post-polyribosommaRl NP fraction of duck reticulocytes. Preparations of deproteinized mRNA isolated fromthe polyribosomal and postpolyribosomal subfractions of duck reticulocytecytoplasm showcomparabletemplateactivity when translated in vitro in a nuclease-treated rabbit reticulocyte lysate.The ”S-labeled translationproducts of the respective mRNA populations separated by two-dimensional electrophoresis areshownin Fig. 1.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.