Identification of C3H2C3-type RING E3 ubiquitin ligase in grapevine and characterization of drought resistance function of VyRCHC114.
BACKGROUND
RING is one of the largest E3 ubiquitin ligase families and C3H2C3 type is the largest subfamily of RING, which plays an important role in plant growth and development, and growth and responses to biotic and abiotic stresses.


RESULTS
A total of 143 RING C3H2C3-type genes (RCHCs) were discovered from the grapevine genome and separated into groups (I-XI) according to their phylogenetic analysis, and these genes named according to their positions on chromosomes. Gene replication analysis showed that tandem duplications play a predominant role in the expansion of VvRCHCs family together. Structural analysis showed that most VvRCHCs (67.13 %) had no more than 2 introns, while genes clustered together based on phylogenetic trees had similar motifs and evolutionarily conserved structures. Cis-acting element analysis showed the diversity of VvRCHCs regulation. The expression profiles of eight DEGs in RNA-Seq after drought stress were like the results of qRT-PCR analysis. In vitro ubiquitin experiment showed that VyRCHC114 had E3 ubiquitin ligase activity, overexpression of VyRCHC114 in Arabidopsis improved drought tolerance. Moreover, the transgenic plant survival rate increased by 30 %, accompanied by electrolyte leakage, chlorophyll content and the activities of SOD, POD, APX and CAT were changed. The quantitative expression of AtCOR15a, AtRD29A, AtERD15 and AtP5CS1 showed that they participated in the response to drought stress may be regulated by the expression of VyRCHC114.


CONCLUSIONS
This study provides valuable new information for the evolution of grapevine RCHCs and its relevance for studying the functional characteristics of grapevine VyRCHC114 genes under drought stress.
['Yu|Yihe|Y|', 'Yang|Shengdi|S|', 'Bian|Lu|L|', 'Yu|Keke|K|', 'Meng|Xiangxuan|X|', 'Zhang|Guohai|G|', 'Xu|Weirong|W|', 'Yao|Wenkong|W|', 'Guo|Dalong|D|']
D017360:Arabidopsis D029681:Arabidopsis Proteins D002874:Chromosome Mapping D003681:Dehydration D055864:Droughts D018506:Gene Expression Regulation, Plant D018745:Genome, Plant D050698:Glutamate-5-Semialdehyde Dehydrogenase D009097:Multienzyme Complexes D017853:Phosphotransferases (Alcohol Group Acceptor) D010802:Phylogeny D010940:Plant Proteins D030821:Plants, Genetically Modified D011401:Promoter Regions, Genetic D000072417:Protein Domains D044767:Ubiquitin-Protein Ligases D027843:Vitis
RING Ubiquitin Grapevine Drought stress Overexpression