Drought Tolerance Allelic Variations And Molecular Character Analysis Of SNAC Transcription Factor In Maize

It's a new ideas for drought tolerance molecular breeding to find elite allelic variations of ZmNAC080308 and its promoter region to acquire drought tolerance functional haplotypes by association analyses based on SNP markers.And molecular characters from ZmNAC080308 transcription factor(TF)were also analyzed.It could provide important stress resistance gene resource.For one thing,The full long of ZmNAC080308 gene,including promoter,5'UTR,ATG-TGA and 3,UTR was producted by PCR in 199 inbred lines.Type of polymorphisms,nucleotide diversity,LD and association analyses of ZmNAC080308 full long sequences with seven drought tolerance phenotype traits in the inbred lines under the environment for WS and WW were analyzed by Tassel.Meanwhile,we should find advanced haplotype.For other thing,the coding region of ZmNAC080308 TF was isolated by PCR,and analyzing amino acid sequence by bioinformatics.We test expression of ZmNAC080308 under various stress treatments in roots,stems and leaves by qPCR.At the same time,the subcellular localization and transactivation analysis in yeast for ZmNAC080308 TF were verified.These are results1.SNP was mainly distributed in the promoter,5'UTR and exon?.The type of SNP were G/A and C/T mainly,and their mutation frequency was 29.07%respectively.The C/A mutation was the lowest(6.98%).In/Del was distributed in promoter,5,UTR region and non-coding region completely.The frequency of insertion and deletion mutation was 56%and 44%respectively.The trend of polymorphism(?,?)was consistent,with high nucleotide polymorphisms and diversity in promoter and exon?.The SNP in promoter,5'UTR,ATG-TGA region had complete or strong LD each other.Decay of LD in ZmNAC080303 gene and promoter sequences occurs at around 500bp2.Association analyses for genotype and phenotypic data showed:under drought conditions(WS),site 235 and ASI was associated;There are 37 sites associating with DTA significantly,which contains LD sites 1774,1880,1901,1902,1912,1971,1984,1989,1998,2013;2763,2787;2850,2880,2913,2917.In addition,LD sites 2763,2787;2850,2880,2913,2917 are also associated with DTS.And LD sites 2850,2880,2913,2917 is also associated with DTS under normal moisture conditions(WW).It is important for those sites to associated with maize flowering-related phenotypic traits.Under WS,genotype of ZmNAC080308 full long and Earn,GY and Kern were correlated significantly,and most of associated sites were located in promoter region.Under WW,only site 2731 was associated with Earn,and no site association with GY and Kern.It is suggested that ZmNAC080308 has the effect to regulated drought stress and maize yield traits.Under WS,sites 787,1060 were associated with plant height(PH);Under WW,detecting 23 sites were associated with PH,which contains 17 of complete LD sites:2441,2461,2505,2532,2548,2563,2565,2575,2595,2631,2646,2648,2673,2730,2739,2856,2919.The 199 of maize NL-inbred lines were divided into 11 haplotypes.Hap-9 contains favorable flower characteristics,and Hap-11 contains high yield characteristics3.The molecular characterization of ZmNAC080308 TF,which encodes 308 amino acids,containing five subdomains that were similar to other NAC TF.And it has high homology with stress responsive NAC TF.The expression analysis of ZmNAC080308 was a little affected by tissue specificity.But ZmNAC080308 expression can be induced by various abiotic stress and the difference is greater.Transient expression in maize protoplast and transactivation assay demonstrated that ZmNAC080308 was localized in the nucleus and had transactivation activity.