巨峰葡萄半乳糖醛酸转移酶基因GAUT克隆及在摘心处理下的表达分析OA北大核心CSTPCD

Galacturonosyltransferase(GAUT)serves as a pivotal enzyme in the pectin biosynthesis and plays a crucial role in orchestrating the growth and development of plant tissues and organs such as cell walls within stems and leaves.To investigate the expression of GAUT in grape stems and leaves after shoot-pinching treatments,using Kyoho grapes(Vitis labruscaxVitis vinifera)as the material,the VvGAUTs genes were cloned,the gene structures and functions were predicted and analyzed by bioinformatics methods,and their expression patterns in Kyoho grapes after shooting-pinching treatments were analyzed with quantitative real-time PCR(qRT-PCR).The results indicated that four GAUTs genes were cloned from the Kyoho grapes,with open reading frame(ORF)sequence lengths of 1 056,1 167,1 038 and 1 071 bp,encoding 351,388,345 and 356 amino acids,respectively.The sequence homology with the corresponding genes in the grape genome database exceeded 98％,thus designated as VvGAUT1a,VvGAUT1b,VvGAUT3 and VvGAUT4a.The encoding protein of VvGAUT1a is stable,while other three proteins are unstable.The VvGAUTs exhibit close interactions with proteins associated with cellulose,lignin,and glucose metabolism.Significant differences were observed in the expression patterns of VvGAUTs in stems and leaves of Kyoho grapes subjected to different shoot-pinching treatments.In general,2-leaf pinching treatment suppressed the expression of VvGAUTs genes in Kyoho grapes stems,while their expressions in leaves exhibited an increasing trend during early growth and subsequent inhibition during late growth.Furthermore,the expression levels of VvGAUT1a,VvGAUT1b and VvGAUT3 genes in both stems and leaves of Kyoho grapes were significantly higher during the early stage of growth compared to the late stage.Conversely,VvGAUT4a was upregulated in the stems at late stage,while its expression levels remained relatively stable in the leaves.These findings in this study suggested that shoot-pinching treatments regulated the expression of VvGAUTs genes in Kyoho grapes,thereby potentially play a crucial role in modulating stem and leaf growth,as well as balancing vegetative and reproductive growth.It provides a theoretical foundation for underlying the molecular mechanisms in regulation of grapevine growth through shoot-pinching.