Enhancer mutant of asymmetric leaves 2 mutant that is involved in the adaxial-abaxial polarity of leaves in Arabidopsis

Abstract

Loss-of-function mutations in the ASYMMETRIC LEAVES2 (AS2) gene in Arabidopsis result in various defects in leaf development, such as formation of asymmetrically lobed and downwardly curled leaves, formation of leaflet-like structures from petioles, generation of an abnormal venation system, shorter length of petioles and leaf laminas than WT, and ectopic expression of class 1 KNOX genes in the leaves. To uncover the function of AS2 in the leaf development, we screened enhancer and suppressor mutants of as2. We obtained several enhancer candidates. #16 mutant, one of enhancer candidates, showed filamentous leaves in as2 mutant background and pointed leaves in wild-type background. In high temperature condition, #16 mutant showed filamentous leaves in as2 mutant background and narrow leaves in wild-type background, suggesting sensitivity to high temperature. From map-based cloning, it was showed that #16 mutation mapped to the lower arm of chromosome 5.