Functional Analysis Of Wheat NTL5-7B Transcription Factor In Resistance To Stripe Rust And Leaf Spot

NTL(NAC WITH TRANSMEMBRANE MOTIF1-LIKE,NTM-LIKE)class of transcription factors(TFs)belong to the NAC transcription factor family.NTLs are characterized by the transmembrane domain at the C terminus in addition to the NAC domain,they are membrane-bound transcription factors.The number of NTLs is small compared to the huge members of plant specific NAC TFs.NTLs have been shown to play an important role in plant development response to biotic and abiotic stresses.Ta NTL5-7B(Traes CS7B02G196900.1)was a novel NAC TF isolated from a full-length c DNA library of near-isogenic line Taichung29*6/Yr10 infected by stripe rust race CY32,there are 5 exon and 4 introns in the sequence.Genome-wide of NTLs and their expression patterns responded to wheat stripe rust were analyzed in wheat.In order to characterized Ta NTL5-7B in wheat resistant to stripe rust different molecular methods were used,include q RT-PCR,Virus induced gene silence,gene overexpression,yeast one hybridize and protein subcellular location.The mainly results include:1.A total of 19 NTLs transcription factors were identified by bioinformatics analysis of the wheat reference genome,which belong to 7 homologous groups and located on 14 chromosomes.In addition,the expressions of some Ta NTLs transcription factors were induced by the infection of wheat stripe rust(Puccinia striiformis Westend f.sp.tritic,Pst).2.The expression level of Ta NTL5-7B was highest at 96 h post infection of Pst.Plants with knockdown of Ta NTL5-7B by BSMV-VIGS(Barley Stripe Mosaic Virus induced gene silencing)incubated compatible Pst showed with higher severity,more spore piles per unit area and higher level of fungi biomass.Overexpressed Ta NTL5-7B lead to lower severity,less spore piles per unit area and lower level of fungi biomass in T3 plants inoculated compatible Pst.While inoculated incompatible Pst lead to lower area of necrosis,higher level of hydrogen peroxide indicted by DAB stain.Overexpressed Ta NTL5-7B plants inoculated wheat spot blotch(Bipolaris sorokiniana)showed no significant chlorosis between infection area and health area.These findings demonstrated that Ta NTL5-7B acts as a critically positive regulator for wheat stripe rust and spot blotch resistance.3.Transactivity analysis of Ta NTL5-7B different length in yeast showed Ta NTL5-7B with transcription activation and the transcription activation motif located at 149-620 aa.e GFP fusion protein expressed in tobacco leaf epidermal cells showed Ta NTL5-7B and without trans membrane domain(Ta NTL5-?C)located at membrane and nucleus,but Ta NTL5-7B showed higher e GFP expression than Ta NTL5-?C at membrane.Further analysis showed the lipid modifications N-Myristoylation and S-Palmitoylation may lead the protein relocation of Ta NTL5-7B.