this enabled us to identify where in the determined dna sequence the 21s ribosomal rna and the precursor for 15s ribosomal rna ( 15.5s rrna ) start , since both transcripts are initiated de novo ( levens et al . ( 1981 ) j.biol.chem. , 256 , 5226-5232 ) .
C0035701
ribosomal rna
C0035553
ribosomal