Functional Analysis Of Transcription Factor EREB58 Inresponse To Herbivore In Zea Mays

Maize is a very important staple crop and industrial raw material in our country and it plays an important role in promoting the development of national economy. But the serious herbivore damage is one of the key factors to maize yield loss. In the long process of evolution, maize had developed a set of precision indirect defense mechanism to defense against herbivores. The maize terpene synthetases(TPSs) were an important part of indirect defense mechanism. The results showed that the maize transcription factor EREB58 could regulate the maize terpene synthetases gene(TPS10) expression and could lead to strengthen the resistance to herbivore in maize. EREB58 belongs to ERF transcription factor family and there are a lot of literature about ERF transcription factors. However, ERF transcription factors involved in resisting herbivore stress literatures were rare.EREB58 was the main research object in this study, and the purpose was to elucidate the expression regulation mechanism of Zm EREB58 gene. The results of quantitative real-time PCR(qRT-PCR) showed that ZmEREB58 gene was inducible in maize leaf by herbivore, MeJA as well as ACC. The cis-elements in the 1193 bp ZmEREB58 promoter were predicted in the Plantcare database. There were a lot of cis-elements in the promoter which related to plant defense, such as ABRE, Box-W1,GARE motif and TCA elements. The results of GUS histochemical staining and GUS enzyme activity analysis in transgenic Arabidopsis harboring different truncated ZmEREB58 promoter-GUS indicated that the region from-323 to-270 and the region from-270 to-183 of the ZmEREB58 promoter were key the promoter function sequence. The region from-323 to-270 of the ZmEREB58 promoter contain cis-acting element inhibiting ZmEREB58 transcription; in the meantime the region from-270 to-183 of the ZmEREB58 promoter was required for transcription. To obtain the transcription factors that regulate ZmEREB58, yeast one hybrid will be used to screen transcription factor library.A high-throughput screening of an Arabidopsis transcription factors library using the N-terminal and C-terminal of the EREB58 protein as the bait identified a bZIP family transcription factors. The bZIP transcription factors could simultaneously interact with N-terminal and C-terminal of the EREB58. The phylogenetic tree and BLAST analysis showed that there were 8 close homolog bZIP transcription factors in maize. Among their 8 close homologs in maize, GRMZM2G131961 was the only suppressed expression by herbivory and MeJA. The primary result showed the antagonistic effect may exist between EREB58 and GRMZM2G131961 that GRMZM2G131961 could inhibit EREB58 function.Results in this study demonstrated the phytohormones could induce expression of ZmEREB58.Then the function sections of promoter and bZIP transcription factors which interact with EREB58 were identified by the study. It is of great significance to parse the regulation mechanism of ZmEREB58 expression and function analysis, and to lay the foundation for further analysis of maize indirect defense molecular regulation network.