Functional Analysis Of Pinus Root-specific Promoters And The Regulation Of Na~+/H~+ Antiporter Expression In Rice

PR10 family consists of proteins with inducible expression pattern by different environmental factors, such as osmotic stress, freezing temperatures, wounding and pathogen infections, suggesting their important biological roles in plant defense response.This thesis studied the functions of the cloned PR10 promoters, PmPgPR10 and PmPsPR10,and selected the minimum sequence of the promoter with 5'-deletion. We also constructed the plant expression vectors with PmPgPR10 (PmPsPR10)::TaNHX2, and transformed them into rice, 47 transgenic rice plants were obtained in all and the transgenic plants were detected by PCR and Southern blotting.The major results are as follows:1. By means of 5'deletion, expression vectors carrying promoters with different regions and GUS gene were constructed and introduced into tobacco, obtaining lots of transgenic plants;2. In order to determine the shortest region necessary for efficient expression of promoter. PmPsPR10-800 (800bp region) was obtained from PR10 and found to have the characteristic of root-specific expression;3. PCR results showed that 62 percent of hygromycin-tolerant plants could amplify a 1.6kb fragment, while no signal was detected in wild type plants;4. Southern blotting analysis indicated that 17 transgenic plants had strong positive signals while wild type plants no signal. It is suggested that TaNHX2 has integraded into the genome of rice.