Genome-wide Identification And Analysis Of The MADS-box Gene Family In Bread Wheat(Triticum Aestivum L.)

The MADS-box genes encode transcription factors with key roles in plant growth and development.A comprehensive analysis of the MADS-box gene family in bread wheat(Triticum aestivum L.)has not yet been conducted,and our understanding of their roles in stress is rather limited.In order to further study the structure,function and expression of MADS gene family in cereal crops.Here,we report the identification and characterization of the MADS-box gene family in wheat.Collectively,the present study provides new insights into the possible roles of MADS-box genes in response to stresses and will be valuable for further functional studies of important candidate MADS-box genes.The results of this research include:1、32,5,5 and 138 wheat MADS-box genes were identified to be Mα-,Mγ-,Mδ-and MIKC-type,respectively.We further mapped these 180 wheat genes to the wheat chromosomes and analyzed their genetic structures and protein motifs.It was shown that,closely related genes generally have a more similar gene structure,and nearly all the wheat MADS proteins had either MADS or K-box domain motifs.2、Evolutionary analysis of the orthologs among T.urartu,Aegilops tauschii and wheat homeologous sequences analysis among the three subgenomes in wheat dentified 33 pairs of T.urartu-wheat A gnome orthologs and 32 pairs of A.tauschii-wheat D genome.This analysis as well as homeologous sequences analysis among the three subgenomes in wheat revealed that gene loss and chromosomal rearrangements occurred during and/or after the origin of bread wheat.3、Forty wheat MADS-box genes that were expressed throughout the investigated tissues and development stages were identified.The genes that were regulated in response to both abiotic stresses(i.e.,phosphorus deficiency,drought,heat,and combined drought and heat)and biotic stresses(i.e.,Fusarium graminearum,Septoria tritici,stripe rust and powdery mildew)were detected as well.A few notable MADS-box genes were specifically expressed in a single tissue and those showed relatively higher expression differences between the stress and control treatment.Meanwhile,the expression patterns of considerable MADS-box genes differed from those of their orthologs in Brachypodium,rice,and Arabidopsis.4、RT-qPCR for six randomly selected genes was carried out to successfully validate their expression pattern observed from the public database based analysis.