Function Analysis of Sugarcane A20/AN1 Zinc‐Finger Protein Gene <i>ShSAP1</i> in Transgenic Tobacco

ABSTRACT We tried to characterize the function of ShSAP1 , a member of the stress‐associated protein (SAP) gene from sugarcane ( Saccharum officinarum L.). The expression of ShSAP1 was much higher in mature part of vegetative organs, and significantly lower in young leaves and roots in mature sugarcane plants. ShSAP1 can be up‐regulated by salt and drought stress in 2‐mo‐old sugarcane seedlings. At the late seedling stage, transgenic tobacco with ShSAP1 exhibited an enhanced tolerance to salt and drought stress, and seven stress‐related genes showed higher expression level in transgenic lines than wild‐type (WT) plants under drought stress. Drought resistance was also presented during the vegetative stage in transgenic plants, as shown by the examination of drought physiological indexes. These results suggest that ShSAP1 plays a positive role in osmotic stress response.