MdXTH30, an apple gene encoding endotransferase/hydrolase for xyloglucan, enhances plant resistance to drought, salt and pathogenic stresses

Xyloglucan is the main component of hemicellulose in the cell walls of higher plants, which provides mechanical support. The XTH gene family encodes xyloglucan endotransferase/hydrolase, which is a key enzyme in cell wall remodeling. However, studies on XTH family-related genes in apples are rare. In this study, the MdXTH30 gene, isolated from apple ( Malus × domestica ), was responsive to abscisic acid, NaCl, and PEG 6000, and was localized to the cytoplasm according to a subcellular mapping technique. To further investigate the role of MdXTH30 in the stress response, we generated transgenic MdXTH30 apple calli and heterologously expressed this gene in Arabidopsis by Agrobacterium -mediated transformation. The results demonstrated that MdXTH30 enhanced resistance to drought, salt stress, and pathogens by regulating the expression of relevant genes in apple calli and Arabidopsis . These findings provide valuable insight into potentially important candidate genes for improving biotic and abiotic stress resistance at the cell wall level.