Genome-wide identification of small heat shock protein (HSP20) gene family in grape and expression profile during berry development

Abstract

Background : Studies have shown that HSP20 (heat-shock protein 20) genes play important roles in regulating plant growth, development, and stress response. However, the grape HSP20 gene family has not been well studied. Results : A total of 48 VvHsp20 genes were identified from the grape genome, which were divided into 11 subfamilies (CI, CII, CIII, CV, CVI, CVII, MI, MII, ER, CP and PX/Po) based on a phylogenetic analysis and subcellular localization. Further structural analysis showed that most of the VvHsp20 genes (93.8%) had no intron or only one intron, while genes that clustered together based on a phylogenetic tree had similar motifs and evolutionarily conserved structures. The HSP20s share a conservedα-crystalline domain (ACD) and the different components of the ACD domain suggest the functional diversity of VvHSP20s. In addition, the 48 VvHSP20 genes were distributed on 12 grape chromosomes and the majority of VvHSP20 genes were located at the proximal or distal ends of chromosomes. Chromosome mapping indicated that four groups of VvHSP20 genes were identified as tandem duplication genes. Phytohormone responsive, abiotic and biotic stress-responsive, and plant development-related cis-elements were identified from the cis-regulatory elements analysis of VvHSP20s. The expression profiles of VvHSP20s genes (VvHsp20-1, 11, 14, 17, 18, 19, 20, 24, 25, 28, 31, 39, 42, and 43) were largely similar between RNA-Seq and qRT-PCR analysis after hydrogen peroxide (H 2 O 2 ) treatment. The results showed that most VvHSP20s were down-regulated by H 2 O 2 treatment during fruit development. VvHSP20s genes were indeed found to be involved in the grape berry development and differences in their transcriptional levels may be the result of functional differentiation during evolution. Conclusions : Our results provide valuable information on the evolutionary relationship of genes in the VvHSP20 family, which is useful for future studies on the functional characteristics of VvHSP20 genes in grape.

Genome-Wide Characterization of the HSP20 Gene Family Identifies Potential Members Involved in Temperature Stress Response in Apple

“…In the present study, we identified 41 HSP20 genes and investigated their characteristics from the apple genome database. The number of apple HSP20 genes was higher than that of Arabidopsis (19) ( Scharf et al, 2001 ), slightly higher than rice (39) ( Ouyang et al, 2009 ) but lower than that of watermelon (44) ( He et al, 2019 ), potato (48) ( Zhao et al, 2018 ), and grape (48) ( Ji et al, 2019 ). This difference is most likely due to the fact that apple had gene duplications during evolution ( Velasco et al, 2010 ; Ma et al, 2018 ).…”

“…In addition, most apple HSP20 genes were classified into CI-CVI, indicating that cytoplasm could be the primary functional area of the HSP20 family in apple. Gene structure has been documented to function directly in the evolution of multiple gene families ( Ji et al, 2019 ). Gene structure analysis indicated that most apple HSP20 genes have no introns (60.9%) or one intron (31.7%), suggesting relatively simple gene structures.…”

“…Gene structure analysis indicated that most apple HSP20 genes have no introns (60.9%) or one intron (31.7%), suggesting relatively simple gene structures. Similarly, most (93.8%) grape HSP20 genes have no introns or one short intron ( Ji et al, 2019 ).…”

“…Nineteen HSP20 genes have been identified in Arabidopsis ( Scharf et al, 2001 ), 39 in rice ( Ouyang et al, 2009 ), 42 in tomato ( Yu et al, 2016 ), 44 in watermelon ( He et al, 2019 ), and 48 in grape ( Ji et al, 2019 ). Previous studies have suggested that HSP20 genes are involved in regulating a diverse array of developmental processes and responses to abiotic stresses, especially in heat stress ( Guo et al, 2015 ; He et al, 2019 ; Ji et al, 2019 ). Yu et al (2016) identified tomato HSP20 family genes and analyzed their functions in abiotic-stress responses.…”

Identification of Ubiquitin Ligase From Grapevine Ring C3H2C3E3 and Characterization of Drought Resistance Function of VyRCHC114

“…Similarly GpDSR7 encodes an E3 ubiquitin ligase, which when overexpressed in Arabidopsis increased its tolerance to drought stress [43]. In our study, and according to previous screening methods [44], we focused on genes which were signi cantly up-regulated or down-regulated at four time periods during the drought treatment, as they more likely to play a key role in grapevine's drought stress response ( Fig. 5b and 5c).…”