SEQUENCE-ANALYSIS OF MOUSE CDNAS ENCODING RIBOSOMAL-PROTEINS L12 AND L18

Mouse cDNAs encoding ribosomal proteins (r-proteins), L12 and L18, wer e isolated and their sequences determined. The L12 cDNA was found to c ontain 639 bp, including a coding sequence of 498 nucleotides (nt), 5' (78 nt) and 3' (45 nt) untranslated regions (UTRs), and a poly(A) tai l of 18 nt. The L18 cDNA was shown to consist of 648 bp, including a c oding sequence of 567 nt, 5' (26 nt) and 3' (39 nt) UTRs, and a poly(A ) tail of 16 nt. The nt sequences of the protein-coding region from th e mouse L12 and L18 cDNAs were found to exhibit 96% and 92% identity, respectively, with those of the rat. With the use of mouse L12 and L18 cDNA probes, multiple (at least 10) copies of the L12 and L18 gene fa milies were shown to be present in the mouse and rat genomes. However, there was no sequence heterogeneity detected among seven L18 cDNA clo nes, indicating that only one copy of the L18 gene-related sequences i s functional, and the other copies are presumably nonfunctional pseudo genes. The complete amino acid (aa) sequences of the mouse r-proteins, L12 and L18, were deduced from the nt sequences of their cDNA clones. L12 has 165 aa and a M(r) of 17790, while L18 has 188 aa and a M(r) o f 21 570. The aa sequences of the mouse r-proteins, L12 and L18, exhib it 98% and 94% identity, respectively, to those of rat.