Cloning And Functional Analysis Of PAB5Gene Promoter In Maize (Zea Mays.L)

Promoter is the most important element for controlling gene expression it could drive gene expression in special time, tissues and decide the level of expression. Tissue-specific promoter, a class of the most useful promoters, can drive gene expression in particular space and time. They can increase transgenic expression in specific organs or developmental stages, and avoid unnecessary energy waste. Therefore, the isolation, identification and application of specific promoters have become a key aspect in transgenic plant researches. Pollen-specific promoter can interfere with pollen production or viability of the gene and lead to infertility, or in the target gene specifically expressed in pollen, so these of maize pollen-specific promoter has certain significance.This study constructs ZMP5promoter of five promoter deletion of rice transformation vector, and then constructed by Agrobacterium transformation vector into the rice, and regenerated plants were obtained. Regeneration of plants were obtained to PCR and GUS staining. The main results were as follows:(l)According to publishing literature PAB5gene in Arabidopsis thaliana protein sequences, we obtained protein gene sequence of PAB5and DNA sequence of the gene.(2)Putative functional promoter elements were analyzed by the PLACE database. The sequences contained the basic elements, such as TATA-box and CAAT-box. Two motifs AGAAA and PolyA-S3were detected which are known to be involved in pollen-specific expression. There were three copies of AGAAA motifs and one PolyA-S3motifs. Many copies of AGAAA and PolyA-S3motifs suggested that this promoter may be a pollen-specific promoter.(3)In order to verify controlling the characteristics of the promoter ZMP5, we analyzed the ZMP55’ deletion promoter, and construct five5’ deletion vectors with the GUS gene fusion, we named them pCam-ZMP5p, p1706, p1198, p777and p365.(4)Transferring all plant expression vectors to rice by Agrobacterium-mediated transformation and several transgenic plants are obtained. By GUS staining, we proved that ZMP5promoter can drive GUS gene expression in rice pollen, but in other tissues were not drive GUS gene expression.PAB5promoters were pollen-specific promoter first isolated from maize. So far further detailed study of this promoter would shed light on understanding the function of PAB5gene and sexual reproduction in maize. PAB5promoter was drive the gene expression in pollen grains would be useful for producing male-sterile plants in which the pollen is normal during microspore development. These promoters could be utilized in plants molecular breeding. It could be help to resolve the problem of transgenic safety. Also it could be applied in transgenic breeding.