Structural determination and characterization of a 40 kDa protein isolated from rat 40 S ribosomal subunit

• Published in: FEBS letters 1994-02, Vol.340 (1), p.133-138
• Main Authors: Tohgo, Akira, Takasawa, Shin, Munakata, Hiroshi, Yonekura, Hideto, Hayashi, Norio, Okamoto, Hiroshi
• Format: Article
• Language: English
• Subjects: 68 kDa laminin binding protein; Amino Acid Sequence; Animals; Base Sequence; cDNA cloning; DNA, Complementary; Humans; Molecular Sequence Data; Protein Conformation; Rat liver; Rats; Ribosomal protein S2; Ribosomal Proteins - chemistry; Ribosomal Proteins - genetics; Ribosomal Proteins - isolation & purification; Sequence Homology, Amino Acid
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(94)80188-6

We have purified a 40 kDa protein from the rat 40 S ribosomal subunit and determined its primary structure by amino acid and cDNA sequencing. The amino acid sequence of the 40 kDa protein shared 29–37% homology with prokaryotic ribosomal protein S2 of eubacteria and chloroplasts, indicating that the protein is a eukaryotic counterpart to prokaryotic S2. Moreover, the amino acid sequence shared 99% identity with those deduced from cDNAs for 68 kDa laminin binding proteins of human, murine and bovine origins. The cDNAs are capable of encoding polypeptides with predicted molecular mass of 33,000 which lacked typical signal sequences, N-linked glycosylation sites and putative transmembrane domains. These results indicate that the eDNAs for 68 kDa laminin binding proteins actually code for the 40 kDa ribosomal protein.