Role of salivary proline-rich protein P-B in cell differenciation.

用RT-PCR方法研究了富含脯氨酸蛋白P-B在牛不同组织中的分布。结果表明，心脏、颌下腺、牙胚和肾脏是P-B表达的主要部位。RT-PCR结果显示，从牙胚组织中获得的P-B mRNA克隆具有两部分嵌合结构，一部分为P-B mRNA，另一部分为大肠杆菌基因组DNA的部分序列。这种嵌合结构是否对P-B的功能或表达有影响尚不清楚。虽然检测到少量的P-B产物，但产量不足以用于功能分析。

Tissue distribution of proline-rich protein P-B was studied by RT-PCR using various bovine tissues. The results indicate that heart, submaxillary gland, tooth germ and kidney are the major sites of P-B expression. The presence of P-B mRNA in tissue other than salivary gland may suggest a fundamental physiological role of this protein.A clone obtained from tooth germ mRNA by RT-PCR had a chimeric structure composed of two parts, one corresponding to P-B mRNA and the other to the partial sequence of E.coli genomic DNA. Whether this chimeric structure has effects on the function or expression of P-B is not known.Production of P-B by E.coli using pCold shock vector I was tested. Although small amount of P-B production was detected, the yield is not enough for function analysis.