Cloning and Sequence Analysis of Three Defensin Genes in Wheat (Triticum aestivum L.)
Shi Lingmin
Zhang Bin
Ding Hanfeng
Li Nana
Gao Wenwei
Peng Zhenying
Abstract：Three Triticum aestivum defensin (TaPDF)genes,TaPDF32,TaPDF33 and TaPDF34 (GenBank accession No.BT009185,BT009167 and BT009022),were cloned from the young leaves of Jimai 22 cultivar.Sequence analysis showed that each had an open reading frame of 243,249 bp and 225 bp, which encoded the proteins with 80,82 and 74 amino acids respectively.The mature proteins,with the esti-mated molecular masses of all about 5.5 kD and the isoelectric points all higher than 7,each contained eight conservative cysteine residues.Conserved domain analysis found that TaPDF32 contained a strictly conserved gamma -thionin domain,while TaPDF33 and TaPDF34 each had a Knot1 function domain.Both of the do-mains are the typical characteristics of plant defensin.Thus,the three TaPDFs all belong to typical plant de-fensin proteins.Study of the three dimensional structure using SWISS -MODEL showed that all of them con-tained a triple -stranded anti -parallel β-sheet and an α-helix stabilized by four disulfide bridges.Phyloge-netic analysis showed that TaPDF32 and TaPDF33 were close to defensins of Zea mays and Setaria italica,while TaPDF34 was close to Clycine max defensin.But they all owned low similarities with the other reported wheat defensins,which indicated that TaPDF32,TaPDF33 and TaPDF34 were three new wheat defensins.Real -time PCR analysis revealed that TaPDF32 and TaPDF33 genes had the highest expression level in leaves,followed by seeds,and the lowest level in roots.Whereas TaPDF34 expressed basically consistent in all tissues.
Keywords：Triticum aestivumPlant defensinGene cloningSequence analysisTissue -specific ex-pression
Publication Date：2016-10-31
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：8( 1-8 )