Genomic Analysis of the Glutathione -Transferase Family in Pear () and Functional Identification of in Anthocyanin Accumulation.

Anthocyanin accumulation in vacuoles results in red coloration in pear peels. Glutathione -transferase (GST) proteins have emerged as important regulators of anthocyanin accumulation. Here, a total of 57 PcGST genes were identified in the European pear 'Bartlett' () through comprehensive genomic analysis. Phylogenetic analysis showed that PcGST genes were divided into 10 subfamilies. The gene structure, chromosomal localization, collinearity relationship, -elements in the promoter region, and conserved motifs of PcGST genes were analyzed. Further research indicated that glutamic acid (Glu) can significantly improve anthocyanin accumulation in pear peels. RNA sequencing (RNA-seq) analysis showed that Glu induced the expression of most PcGST genes, among which was most significantly induced. Further phylogenetic analysis indicated that was closely related to GST genes identified in other species, which were involved in anthocyanin accumulation. Transcript analysis indicated that was expressed in various tissues, other than flesh, and associated with peel coloration at different developmental stages. Silencing of by virus-induced gene silencing (VIGS) inhibited the expression of and reduced the anthocyanin content in pear fruit. In contrast, overexpression of improved anthocyanin accumulation. Collectively, our results demonstrated that was involved in anthocyanin accumulation in pear and provided candidate genes for red pear breeding.