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Title: Characterization of proteins and RNAs present on polysomes from normal and heat shocked Drosophila cells

Conference · · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)
OSTI ID:6023367

Translational regulation in heat shocked Drosophila cells is characterized by a shutdown in translation of normal cell mRNA and selective translation of mRNAs coding for heat shock polypeptides. They have characterized the sedimentation profiles and macromolecular compositions of ribosomes and polysomes in normal and heat shocked cells in order to implicate factors responsible for the changes in regulation of translation in heat shocked cells. Sucrose gradient analysis of polysome sedimentation carried out under physiological salt conditions confirms the previously reported decrease in polysomes and increase in 80s monosomes in heat shock. The size of the 40s and 60s subunit peaks and the levels of /sup 35/S-methionyl-tRNA associated with the 43s preinitiation complex do not change significantly in heat shock. Titration of specific mRNA levels across the gradients shows that normal cell mRNAs accumulate in the 40 to 80s region of heat shock profiles while heat shock mRNAs are distributed on heat shock polysomes. Analysis of proteins present on the gradients shows a 46 kD protein is present on polysomes from normal cells and polymerized into the insoluble cytoskeleton in heat shocked cells. The rearrangement of the insoluble cytoskeleton follows the same time course as changes in translation regulation in induction and recovery from heat shock and is accompanied by phosphorylation of the 46 kD polypeptide.

Research Organization:
Robert Wood Johnson Medical School, Piscataway, NJ
OSTI ID:
6023367
Report Number(s):
CONF-870644-
Journal Information:
Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 46:6; Conference: 78. annual meeting of the American Society of Biological Chemists conference, Philadelphia, PA, USA, 7 Jun 1987
Country of Publication:
United States
Language:
English