Abstract
Dicotyledonous plants acquire the bilateral symmetry in addition to the previous radial symmetry at the transition stage as two cotyledon primordia are developing from the apical region of the embryo. Our previous studies show that PIN-FORMED1 (PIN1), which encodes a putative auxin efflux carrier, is essential for the establishment of the bilateral symmetry and that pinoid (pid) enhances the abnormality of pin1 mutation. To isolate new genes involved in the establishment of bilateral symmetry, we screened for mutant loci causing the defects of symmetrical cotyledon formation in the background of pid mutation. We identified three loci except for PIN1 gene and found a point mutation of gene involved in the energy metabolism in one of three mutants. We will present the molecular analyses on these mutants and discuss on the relationship among the loci, auxin, and bilateral symmetry.
