The glyoxalase system, comprising glyoxalase I (GLYI) and glyoxalase II (GLYⅡ), serves as a key mechanism for detoxifying excess methylglyoxal (MG) in plants and plays an important role in responses to abiotic stress and pathogen infection. To date, genome-wide identification and expression analysis of GLY gene family have not been reported in sugarcane. In this study, we identified 50 SsGLYI genes and 52 SsGLYⅡ genes from the wild sugarcane Saccharum spontaneum, and systematically analyzed the physicochemical properties, gene structures, promoter cis-acting elements, and expression patterns. SsGLY genes were randomly distributed across 30 chromosomes. All 43 SsGLYI members contained a conserved Motif1 (PF00903), while all SsGLYII proteins possessed a conserved Motif1 (PF00753). A total of 39 SsGLYI proteins contained four metal-binding sites (H/Q, L, H, E), except SsGLYII8.1-8.4 from subfamily IV, which were Zn2+-dependent, the remaining SsGLYI proteins were Ni2+-dependent. Only 26 SsGLYI proteins contained both the THxHxDH metal-binding domain and the C/GHT active site. Collinearity analysis identified 41 pairs of collinear genes, among which 39 pairs had Ka/Ks values less than 1, indicating that the SsGLY gene family has undergone predominant purifying selection during evolution. The expression levels of SsGLYI subfamily V and SsGLYⅡ subfamily Ⅲ were higher than those of the other four subfamilies under infection by Sporisorium scitamineum. Notably, the expression of SsGLYI3.4 showed differences in its expression patterns between the resistant genotype YT93-159 and the susceptible genotype ROC22. Furthermore, we cloned the homologous gene ScGLYI-1 of SsGLYI3.4 from YT93-159, which was constitutively expressed and primarily localized to the chloroplast. Meanwhile, the expression of ScGLYI-1 could be up-regulated by exogenous salicylic acid (SA) and smut pathogen stress, indicating that this gene may play a crucial role in response to pathogen stress in sugarcane. This study would provide a theoretical foundation for further elucidating the function of glyoxalase genes in sugarcane.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |