Amino acid substitutions in grapevine (Vitis vinifera) acetolactate synthase conferring herbicide resistance

Abstract Acetolactate synthase genes (ALS) have successfully been modified for providing resistance to ALS-inhibiting herbicides in many plant species. Based on sequence and expression analyses, we confirmed VvALS1 as the best functional ALS candidate grapevine. To develop an ALS-based herbicide selection system facilitating grape transformation, firstly evaluated responses of Vitis vinifera cv Chardonnay callus young vitro shoots Thompson Seedless several representative found a typical linear response curves some herbicides, including chlorsulfuron imazapyr belonging sulfonylurea or imidazolinone families, respectively. Secondly, created constructs containing amino acid substitutions domains which are known be critical generated transgenic plants 3 using Agrobacterium-mediated transformation meristematic bulk tissues Seedless. Finally, showed that ectopic two (P191S P191T) at N-terminal region another (W568L) C-terminal VvALS resulted high shoots. Our work highlighted potential use mutations imparting selectable marker grapevine research means fostering improvement via cisgenesis, paving way developing co-editing facilitate transgene-free gene-editing.