Discrete poly(A)-RNA species from rat liver mitochondria are fragments of 16S mitochondrial rRNA carrying its 5′-termini

During electrophoresis in polyacrylamide gels containing 7M urea the major descrete components of preparations of rat liver mitochondrial poly(A) and poly(A) RNA species have similar mobilities. Poly(A) RNA components hybridize to the 16S rRNA gene of mtDNA. Analysis of 5′-terminal sequences of these components revealed their identity to the 5′-terminal sequence of 16S rRNA. These results show that poly(A) RNA components are fragmentation products of 16S rRNA. Fragmentation occurs nonrandomly from the 3′-end of the original rRNA molecules and lead to formation of products with electrophoretic mobilities similar to those of poly(A) RNA components. © 1983 Dr W. Junk Publishers.