Abstract
The acuminate (ac) mutant in the Japanese morning glory (Ipomoea nil) was isolated in the Edo period. It has compound leaves with deeply split lobes and corolla with pleated petals. From these phenotypes, responsible gene for ac mutation is thought to be HD-ZIPIII, ASYMMETRIC LEAVES 1 (AS1) or AS2. The linkage analysis between ac mutant phenotype and these orthologous genes showed that the ac mutant corresponds to the AS1 orthlog. The transcription level of AS1 ortholog was very low in ac background and there is a large 3 kb deletion at 1.9 kb upstream region of AS1 ortholog in all of 22 ac strains analyzed. Double mutants between ac and other morphological mutants were constructed. Combination with maple-willow (m-w) which is a mutant of a WOX1 ortholog or polymorphic (py) mutants showed extremely enhanced phenotypes, suggesting that AC controls MAPLE gene involoved in cell-proliferation along medial-lateral axis. Although the responsible gene of py has not been isolated, it may correspond to a gene controlling adaxial organ development such as HD-ZIPIII.
