Abstract: | Myosin messenger ribonucleoprotein-translational control ribonucleic acid (mRNP-tcNA) from myosin mRNPs found in embryonic chick muscle has been further purified by Dowex chromatography and, from a number of controls, it is suggested that this small RNA is not an artifact produced through the degradation of RNA during its isolation. This highly purified myosin mRNP-tcRNA is shown to have a molecular weight of 10 000 on formamide-acrylamide gels, and reacts stoichometrically (on a 1:1 mole ratio) with myosin mRNA. The stoichiometric interaction between myosin mRNA and myosin mRNP-tcRNP is demonstrated by ists ability to increase the nuclease resistance of the messenger, as well as inhibit its translation in a cell-free amino acid incorporating system. |