Genome-Wide Identification of Grapevine's C3H2C3 Type RING E3 Ubiquitin Ligases Family Reveals VyRCHC114, which Confers Tolerance to Drought Stresses

Abstract

RING is one of the largest E3 ubiquitin ligase families, playing an important role in plants' development and growth and their biotic and abiotic stress responses. The C3H2C3 type is the largest subfamily of RING. Here, 143 C3H2C3-type RING genes (RCHCs) were discovered from the grapevine genome and separated into groups (I˜XI) according to their phylogenetic analysis, with these genes named according to their positions on chromosomes. Gene replication analysis showed that 26 group segmental duplications and 14 tandem duplications of VyRCHCs were identified. All VyRCHCs have introns, VyRCHC29 has a maximum of 19 introns and 96 VyRCHCs have introns of 1 to 3. ARE, ABRE and O2 site Cis-acting elements very conservative in the promoter of VyRCHCs, with a large number. The expression profiles of eight DEGs in RNA-Seq after drought stress were similar to those in qRT-PCR analysis. The in vitro ubiquitin experiment showed that VyRCHC114 had E3 ubiquitin ligase activity, while Arabidopsis thaliana overexpressing VyRCHC114 had stronger tolerance of drought stress than the control. Valuable new information on the evolution of grapevine RCHC family genes and its relevance for studying the functional characteristics of grapevine VyRCHC114 genes under drought stress emerged from this research. Recent studies have shown that the RING E3 ubiquitin ligase plays a key role in biological stress responses of plants. For example, in tobacco,NtRFP1 encodes the C3-H-C4 type RING E3 ligase, which can diminish the