Polysomal and cytoplasmic mRNP particles containing 7S (L) RNA.

Nuclear RNP complexes, cytoplasmic mRNP particles and free and membrane-bound polysomes were prepared from rat liver and their tow-molecular-muss RNA components were analyzed on polyacrylamide/formamide gels. The separated small RNAs transferred to diazophenylthioether paper were hybridized to the nick-translated recombinant plasmid pA6 containing cDNA sequences for the low-M_r RNA called 7S(L) RNA. Nuclear RNP particles and free and membrane-bound polysomes were found to contain 7S(L) RNA. In the cytoplasm 7S(L) RNA could be identified as the major small RNA in 20-S cmRNP particles. [ABSTRACT FROM AUTHOR]