The role of ribosomal ribonucleic acid in the structure and function of mammalian brain ribosomes.

摘要: Abstract In order to resolve the functional role of intact rRNA in polypeptide chain elongation mouse brain ribosomes were treated with dilute pancreatic or T1 RNAase (ribonuclease). After treatment, several physical–chemical properties as well activity measured. treatment resulted extensive hydrolysis both 18S and 28S rRNA; however, sedimentation mono-ribosomes unaltered more than 90% relatively low-molecular-weight RNA fragments remained associated ribosome particles. Analysis ability RNAase-treated participate cell-free protein synthesis showed that less 2% retained 85% their polyphenylalanine incorporation. Proof incorporation phenylalanine by hydrolysed actually represented active translocation was obtained effective inhibition diphtheria toxin. In addition, oligopeptide products could be identified BD (benzoylated diethylaminoethyl)-cellulose column chromatography. size distribution oligopeptides synthesized normal no significant differences which indicated there change proportion engaged synthesis. Thus strong RNA–protein protein–protein interactions must serve maintain integrity even when is extensively degraded. The enzyme-treated efficiently incorporate amino acids clearly demonstrated `intact' not required for protein-synthetic activity.