FZP, an ethylene-responsive transcription factor, regulates grain size by mediating cell proliferation and expansion. fzp-12 mutant (loss of function) produces smaller grains than the wild type. FZP affects grain length and width as well as grain yield via downregulation of GW7, SRS5, GS3, GS5, and GW8 genes in fzp-12 panicles as compared to wild type (Ren et al., 2018).