Drought, high salinity and low temperature severely damage plant cells, inhibit plant growth, and significantly reduce crop yields. Ethylene-responsive factors (ERFs) in the AP2/ERF superfamily play a key role in plant growth and development, and in stress responses. To investigate the role of MeERF127 in the response of cassava to abiotic stress, this study cloned the MeERF127 gene from cassava and conducted sequence alignment, subcellular localization, transcriptional activity analysis, and expression pattern analysis. A gene-edited vector for MeERF127 was constructed to obtain transgenic cassava, and the phenotype and physiological indicators after drought, salt and cold stress treatments were analyzed, along with the expression of stress-responsive genes. The results showed that the full-length CDS region of the MeERF127 gene was 711 bp, and the amino acid sequence contained YRG and RAYD elements at the N- and C-termini, respectively, with alanine and aspartic acid at positions 14 and 19, indicating that MeERF127 belonging to the ERF subfamily. MeERF127 was localized in the nucleus and had transcription factor activity. MeERF127 was most highly expressed in stems, with the lowest expression in callus tissues, and its expression peaks during the tuber formation stage (80 days after planting). Its expression level increased after drought and salt stress and slightly decreased after cold stress. A gene-edited vector was constructed, and Agrobacterium-mediated transformation of cassava callus tissues resulted in MeERF127 gene-edited lines with 22 and 3 base pair deletions, as confirmed by Hi-TOM high-throughput sequencing. After drought and salt stress treatments, the gene-edited cassava did not wilt, while the wild-type cassava showed significant wilting. The gene-edited cassava had significantly higher SOD and POD enzyme activities and Pro content, and significantly lower MDA content compared to the wild-type cassava. The leaf color of the gene-edited cassava was lighter, and the expression levels of stress-responsive genes SOD and WRKY31 were significantly higher in the gene-edited cassava than those in the wild-type. After cold stress, both gene-edited and wild-type cassava wilted, with no significant differences in SOD and POD enzyme activities, MDA content, leaf color and stress-responsive gene expression between the gene-edited and wild-type cassava. These results suggest that the gene-edited MeERF127 enhances the drought and salt tolerance of cassava but does not respond to cold stress, indicating that MeERF127 may regulate the SOD and WRKY31 genes to respond to drought and salt stress. The findings of this study would provide insights into the role of the MeERF127 gene in cassava's response to drought and salt stress.
| 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 |