Genome-wide analysis of glyoxalase-like gene families in grape (Vitis vinifera L.) and their expression profiling in response to downy mildew infection

Abstract

Background: The glyoxalase system usually comprises two enzymes, glyoxalase I (GLYI) and glyoxalase II (GLYII). This system converts cytotoxic methylglyoxal (MG) into non-toxic D-lactate in the presence of reduced glutathione (GSH) in two enzymatic steps. Recently, a novel type of glyoxalase III (GLYIII) activity has observed in Escherichia coli that can detoxify MG into D-lactate directly, in one step, without a cofactor. Investigation of the glyoxalase enzymes of a number of plant species shows the importance of their roles in response both to abiotic and to biotic stresses. Until now, glyoxalase gene families have been identified in the genomes of four plants, Arabidopsis, Oryza sativa, Glycine max and Medicago truncatula but no similar study has been done with the grapevine Vitis vinifera L. Results: In this study, four GLYI-like, two GLYII-like and three GLYIII-like genes are identified from the genome database of grape. All these genes were analysed in detail, including their chromosomal locations, phylogenetic relationships, exon-intron distributions, protein domain organisations and the presence of conserved binding sites. Using quantitative real-time PCR analysis (qRT-PCR), the expression profiles of these genes were analysed in different tissues of grape, and also when under infection stress from downy mildew (Plasmopara viticola). The study reveals that most VvGLY-like genes had higher expressions in stem, leaf, tendril and ovule but lower expressions in the flower. In addition, most of the VvGLY-like gene members were P. viticola responsive with high expressions 6-12 h and 96-120 h after inoculation. However, VvGLYI-like1 was highly expressed 48 h after inoculation, similar to VvPR1 and VvNPR1 which are involved in the defence response. Conclusions: This study identified the GLYI-like, GLYII-like and GLYIII-like full gene families of the grapevine. Based on a phylogenetic analysis and the presence of conserved binding sites, we speculate that these glyoxalase-like genes in grape encode active glyoxalases. Moreover, our study provides a basis for discussing the roles of VvGLYIlike, VvGLYII-like and VvGLYIII-like genes in grape's response to downy mildew infection. Our results shed light on the selection of candidate genes for downy mildew tolerance in grape and lay the foundation for further functional investigations of these glyoxalase genes.

From methylglyoxal to pyruvate: a genome-wide study for the identification of glyoxalases and D-lactate dehydrogenases in Sorghum bicolor

“…Glutathione is used in the first reaction catalysed by GLYI but is recycled in the second reaction catalysed by GLYII. D-lactate is further metabolized to pyruvate through Dlactate dehydrogenase (D-LDH) enzyme which passes electrons to cytochrome C (CYTc) Very recently, 4 GLYI and 2 GLYII genes encoding putative functionally active glyoxalase isoforms have also been identified in grapes [22]. Similarly, a recent comparative analysis of glyoxalases genes in Erianthus arundinaceus and a commercial sugarcane hybrid has led to the identification of 9 GLYI and 7 GLYII genes in sugarcane, with the wild cultivar showing higher expression of glyoxalase genes under stress conditions than the commercial variety [23].…”

Glyoxalase I‐4 functions downstream of NAC72 to modulate downy mildew resistance in grapevine

“…As we have shown, VvGLYI‐4 plays important roles in P . capsici infection in tobacco and P. viticola resistance in grapevine (Li et al., 2019). We used its promoter to screen the potential targets by Y1H screening and found one transcription factor, VvNAC72 .…”

“…In a previous study we identified several GLYI genes in the transcriptome of grapevine and found that they potentially contribute to pathogen defense. In particular, the expression of VvGLYI‐4 was strongly increased after grapevine leaves were inoculated with P. viticola (Li et al., 2019). However, how the plant defense mechanism causes VvGLYI‐4 to be highly expressed in response to downy mildew infection remains unclear.…”

Genomic identification, Characterization and Expression Analysis of Glyoxalase Gene Family in Brassica Napus L.

“…In recent study, the glyoxalase enzyme of rice not only increased tolerance abiotic stresses (salinity, drought and extreme temperatures) but also reduced damage from biotic stresses (Rhizoctonia solani) [43]. Moreover, in grape, most glyoxalase genes had two periods of high expression after downy mildew inoculation [22]. In our study, the induced genes after infection may have response on the S. sclerotiorum pathogen, e.g., BnaGLYI07, BnaGLYI24, BnaGLYI25, BnaGLYII02, BnaGLYII03, BnaGLYII18 and BnaGLYII19 genes, whose expression were signi cantly up-regulated in both cultivars.…”

“…Moreover, GLYI and GLYII genes were present as multi-gene families. To date, genome-wide identi cation of glyoxalase family has been carried out in six plant genomes Arabidopsis thaliana, Oryza sativa, Glycine max, Medicago truncatula, Brassica rapa and Vitis vinifera L. [17,[22][23][24][25][26]. There are at least 11 GLYI homologous genes in A. thaliana and rice, twenty-four GLYI members in soybean genome, and 15 in B. rapa.…”