Isolation And Function Analysis Of TaSOC1-like Genes In Wheat

Wheat(Triticum aestivum L.)is one of the three major grain crops in the world.The heading time has significant influence on the wheat yield.In order to understand the molecular mechanism of the flowering regulation,a MADS-box gene was isolated from wheats and named SOC1-like.Its expression pattern and biological functions were analyzed in this study.The main results are as follows:TaSOC1-like genes has three alleles that are located on chromosome 6A,6B and 6D,respectively.The sequence homology among the nucleotides is as high as 97.08%.The total length of the genome DNA sequence is 6739 bp(TaSOC1-like-6A),7205 bp(TaSOC1-like-6B)and 7029 bp(TaSOC1-like-6D),respectively.Gene structure analysis showed that these three genes contained six exons and five introns.These genes belong to the MADS-box family.TaSOC1-like protein contains two conserved domains named MEF2-like domain and K-box domain,which are typical MIKC proteins.The phylogenetic tree analysis showed that TaSOC1-like protein had the highest homology with HORVU6Hr1G002330 protein.The result of subcellular localization showed that TaSOC1-like protein was localized in the nucleus.TaSOC1-like genes were widely expressed in various tissues in wheat.Among them,the expression levels in inflorescence at double ridges stage were highest.The results of in situ hybridization showed the similar expression pattern.In order to investigate the function of TaSOC1-like,we used RNA interference strategy to reduce the expression of TaSOC1-like gene in wheat.Nineteen TaSOC1-like-RNAi positive transgenic lines were obtained.The heading date of transgenic wheat was earlier for 6-7 days than control under the long-day conditions in the chamber.While,the heading date of transgenic wheat was earlier for 5-6 days under the nature condition in the field.These results suggest that TaSOC1-like gene may be involved in the regulation of wheat heading date.The phenotype observation showed that other agronomic traits of TaSOC1-like transgenic wheat also changed.For example,plant height of transgenic lines was higher than control and the tiller number of transgenic plants also significantly reduced.Taken together,TaSOC1-like plays an important role in the wheat heading date,which will be helpful to understand the molecular mechanism of wheat development.