Gain-of-function mutations: Key tools for modifying or designing novel proteins in plant molecular engineering

Abstract

Forward and reverse genetics approaches are useful for analyzing the function of target genes. However, most lossof- function mutants do not produce agriculturally useful phenotypes and are usually recessive, making hem difficult to use directly in crop improvement. Many gain-of-function mutations have been identified or developed; however, the gain-of-function alterations that change protein function in plants remain poorly understood. In this issue, Deng et al. (2020) observed that Photoperiod–thermo-sensitive dwarfism 1 (Ptd1) is a conditional gain-of-function mutation that results in a dominant dwarf phenotype and is caused by the deletion of two specific disulfide bonds in an eight-cysteine motif of a non-specific lipid transfer protein.