The Maize Transcription Factor ZmpPTF1Cloning And Genetic Specify Analysis Of Some Related Genes Of Preharvest Sprouting Expression

bHLH transcription factor family is a class of plant transcription factors, studies have shown that the bHLH transcription factor involved in several biological processes during their growth, such as light-responsive, plant hormone response, defense response, seed development and germination. ZmPTF1is a member of bHLH transcription factor family, the experiments confirmed that the bHLH transcription factor ZmPTFl through the regulation of fructose1,6-diphosphate enzymes, sucrose phosphate synthase (SPS1), the conversion enzyme (Ivrl, and Ivr2b) and expression of sucrose synthase (SUS1, SUS2, Sh1B) in low phosphate involved in the sugar allocation, which plays an important role in the tolerance of the plant phosphorus and regulats root hair development. Preharvest sprouting occurred with a variety of plant hormones such as abscisic acid, gibberellin and other related factors affecting plant hormone synthesis, such as sugar, NO, and enzyme proteins.The expression of related gene changed will caused preharvest sprouting. In this study both ZmPTF1and other related genes are down regulated in the embryo, suggesting that they have some relationship with this phenomenon. To further understand the role of ZmPTF1in preharvest sprouting, we focus on ZmPTF1and their associated genes, so we have done a series of studies, the main findings as follows:(1)The A318Inbred bHLH transcription factor family members ZmPTF1open reading frame of1446bp was cloned, which consists of481amino acids,and it is hydrophobic proteins.(2)Builded PET32a-ZmPTF1expression vector, and transferred to the BL21and Rosetta2expression strains, got about50.7KD protein.(3)Using recombinant DNA technology to construct a ZmPTF1coding reading frame (ORF) inserted into the corresponding sites of expression vector PR1101-AN, and build the plant binary expression vector PRI101-ZmPTF1. Further transformed into Agrobacterium transformation of tobacco, for identification ZmPTFl function(4)We analysis specific expression of ZmPTF1transcription factor and other related genes in the preharvest sprouting process by Real-Time Quantitative PCR, Which revealed transcription factor directly or indirectly related with these genes in the preharvest sprouting process. These gene contain the sleep/growth hormone-related protein, phosphate ethanolamine N-methyltransferase, class dehydrationprime, LEA late embryonic stage rich protein, nitrite reductase and WRKY transcription factor. These genes were specific expression after20days of pollination.The analysis shows that WRKY transcription factors and bHLH transcription factors are involved in carbohydrate metabolism and transporlion, which affect the metabolic pathways of ABA and GA, lead to the maize preharvest sprouting occurs. Sleep/growth hormone-related protein may effect hypocotyl development or have effect in the process of dormancy release and preharvest sprouting process. Dehydrin and LEA protein classes have role of regulation and control in the tolerance that proved impacted the exprssion of the bHLH transcription factor in the later period of preharvest sprouting. At the same time, Nitrite reductase expression in the endosperm and embryo is similar to bHLH transcription factor in expression later period, which may proved NO had effect on germination dormancy release.In summary, this study cloned ZmPTF1, got prokaryotic expression and constructed eukaryotic expression vector. In addition, we analysis ZmPTF1and related gene specific expression, which make a contribution for genetic transformation and gene functional verfication.