Translational Activity of mRNA Coding for Cytoskeletal Brain Proteins in Newborn and Adult Mice: A Comparative Study

Abstract

Translational activity of mRNA coding for cytoskeletal brain proteins was used to determine the relative abundance of the mRNA in the brains of newborn and adult mice. mRNA was translated in a cell-free system containing rabbit reticulocyte factors. The products of translation were analyzed by 2-dimensional gel electrophoresis and characterized by peptide map analysis. Comparison of the products of translation from newborn and from adult brain mRNA shows a 50% decrease in actin and tubulin from newborn to the adult stage. The 70 kd [kilodalton] neurofilament protein and glial fibrillary acidic protein show a 2-fold increase in the adult stage. The heat-shock protein HSP70 increases slightly (30%) whereas the brain isozyme of creatine kinase and the heat-shock protein HSP90 are 3 times as high in adult subjects as in newborns.