Changes of main amino acid contents in citrulline biosynthesis pathway and expression analysis of related genes during fruit development of watermelon with different ploidy
The content of four amino acids,glutamic acid,omithine,citrulline and arginine,as well as the expression dif-ferences of key enzyme genes in the citrulline synthesis pathway of citrulline,were studied in the diploid,triploid and tet-raploid Yixuan watermelon.The results showed that the content of citrulline and ornithine in polyploid watermelon fruits were significantly higher than those in diploid,while the content of arginine in polyploid was lower than that in diploid.At 32 days of fruit development,the content of citrulline and ornithine were triploid＞tetraploid＞diploid,while the con-tent of glutamic acid and arginine were diploid＞tetraploid＞triploid.Correspondingly,there were significant differences in the expression of NAGS,NAGK,GAT,OTC genes between polyploid and diploid in the late stage of fruit development,and the expression ofASS1,ASS3 and ARG genes in diploid was always higher than that of polyploid throughout the devel-opmental period.These results indicated that the differences in citrulline content in different ploidy watermelon fruits were caused by the stable differential expression of upstream and downstream genes of citrulline synthesis pathway.This study is of great significance to reveal the mechanism of citrulline content difference in different ploidy watermelon.
万方数据
维普
