NUCLEOTIDE-SEQUENCE OF GENE PBI ENCODING A PROTEIN HOMOLOGOUS TO SALIVARY PROLINE-RICH PROTEIN P-B

The nucleotide sequence of gene PBI, the putative translational produc t of which is homologous to salivary proline-rich protein P-B, has bee n determined. PBI is 6.4 kb long and contains 3 exons, PBI appears to code for the precursor of a proline-rich protein which we have designa ted P-B1. The P-B1 precursor is composed of 134 amino acid residues in cluding 22 residues of signal sequence, 23 residues of N-terminal sequ ence, five repeating units of 13 to 14 residues and 22 residues of C-t erminal sequence, The signal sequence of this precursor is identical w ith that of the P-B precursor, The N-terminal 61 residue sequence of P -B1 has homology of 75% with the whole sequence of P-B (57 residues), when deletion of 4 residues is taken into account, P-B1 is 55 residues longer than P-B, The nucleotide sequence data reported in this paper will appear in the DDBJ, EMBL, and GenBank nucleotide sequence databas es with the following accession number D89501.