Genome-wide Analysis Of AP2/ERF Super Family And Function Analysis Of MaERF25and MaERF27in Banana

Banana (Musaceae, Musa) is a perennial and evergreen large herbs monocotyledon plant and one of the most important food and commercial crops in tropical and subtropical developing countries. Banana is particularly sensitive to most of the abiotic stresses, such as freezing, drought and salt, which cause the yield and quality decreased heavily. Therefore, investigating the molecular mechanism of banana response to abiotic stresses is the basis of improving banana stress-resistant quality and has theoretical and practical significances. ERF family genes play an important role in regulating plant response to abiotic stresses, but the study on system analysis and tolerance to stresses in banana has not been reported. A genome-wide analysis and expression profiles analysis on AP2/ERF super gene family of banana were conducted based on banana A genome sequencing and relative transcriptome results. Moreover, MaERF25and MaERF27were isolated from banana and their basic biochemical characteristics and potential function have been identified by using biology, biochemistry and molecular biology methods. The main results are as follows:(1)119AP2/ERF genes from banana A genome were divided into three families of ERF (100), RAV (15) and soloist (4) according to the number of the AP2/ERF structure domain and whether any other DNA-domain. Based on AP2/ERF conserved domain structure of amino acid sequence homology results, ERF family were classified into ten subfamilies named from I to X. The phylogeny gene structure and putative conserved motifs AP2/ERF protein were analyzed by using MEME and GSDS2.0softwares and the results indicated that proteins in the same subfamily have similar intro-exon structure and conserved motif.(2)The result of heatmap analysis showed that AP2/ERF super family gets the higher gene expression (95.61%) in roots than that of in other issues. When deals with different aboitic stresses, AP2/ERF super family can response to freezing, drought and salinity in transcriptional level, and change the most in suboptimal temperatures (90.9%).(3)MaERF25(GSMUA_Achr2T20280) and MaERF27(GSMUA_Achr10T15510) were chosen as the research object according to genome-wide analysis of AP2/ERF super family, and their CDS sequence were cloned. Sequence analysis confirmed that their CDS sequences have higher consistence with Elaeis, Phoenix dactylifera, Nelumbo nucifera and Vitis vinifera, and MaERF25and MaERF27possessed the basic characteristics of AP2/ERF super family.(4)The Brazil banana seedlings were dealed with4?,300mmol/I mannitol,300mmol/1NaCl and100umol/1ABA, respectively. The physical signs of phenotype, leaf water potential, RWC, IL, MDA and expressions of MaERF25and MaERF27were analyzed. The result suggested that MaERF25and MaERF27were involved in the response to suboptimal temperatures, drought and salinity, and response most significantly to suboptimal temperatures.(5)The plant expression vectors of pCAMBIA1302-MaERF25-GFP and CAMBIA1302-MaERF27-GFP were constructed, respectively. Subcellular localization analysis revealed that MaERF25and MaERF27were located in the nucleus.(6)The yeast expression vectors of pGBKT7-MaERF25/27, pGBKT7-MaERF25/27-N and pGBKT7-MaERF25/27-C were constructed, respectively. The transcriptional activation experiment confirmed the presence of transcriptional activity in the full-length MaERF25and MaERF27protein and their C-terminal domain.All the above results showed that genes in AP2/ERF super family were divided into ERF (100), RAV (15), and soloist (4) families. ERF family contained ten subfamily. The same subfamily has same intro-exon structure and conserved motif domain. Most of genes were deferentially expressed in roots and freezing stress. MaERF25and MaERF27which belonged to Group ? and were responded significantly to cold stress were cloned, and contained AP2/ERF domain. MaERF25and MaERF27protein were located in the nucleus, and had transcriptional activity. MaERF25and MaERF27participated in the reaction responded to freezing, drought, salt and ABA signal response in banana.