Search for the salivary proline-rich peptide P-B related genes

PBI基因是唾液富含脯氨酸蛋白P-B的一个推定翻译产物，其核苷酸序列已被确定。PBI全长6.4kb，包含3个外显子。目前的结果表明，PBI能够编码富含脯氨酸的蛋白前体，我们将其命名为P-B1。P-B1前体由134个氨基酸残基组成，包括信号序列22个残基、n端序列23个残基、13 ~ 14个残基的5个重复单元和c端序列22个残基。该前体的信号序列与P-b前体的信号序列相同。P-B1 n端61个残基序列与P-B全序列（57个残基）相比，考虑4个残基的缺失，同源性为75%。P-B1比b长55个残基。

The nucleotide sequence of gene PBI,a putativetranslational product of which is homologous to salivary prolin-rich protein P-B has been determined. PBI is 6.4kb long and contains 3 exons. The present result indicates that PBI is capable of coding for the precursor of proline-rich protein which we have designated P-B1. The P-B1 precursor is composed of 134 amino acid residues including 22 residues of signal sequence, 23 residues of N-terminal sequence, five repeating units of 13 to 14 residues and 22 residues of C-terminal sequence. The signal sequence of this precursor is identical with that of the P-b precursor. The N-terminal 61 residue sequence of P-B1 has homology of 75% as compared 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.