Abstract
Plant leaves have polarities such as axes along the leaf length and width directions, symmetry and dorsoventrality. However, the molecular mechanisms by which flat structure of leaves is developed are largely unknown. To understand such mechanisms, we isolated and characterized an Arabidopsis activation T-DNA tag line, K346, associated with unusual leaf morphogenesis. K346 showed the dwarfism, and its leaves were depressed and round-shaped. K346 showed semi-dominance, suggesting that the over-expression of a gene caused the phenotypes. The T-DNA insertion site in K346 was found between At2g36980 and At2g36990. But the expression levels of these genes were similar to those of wild type. By a fine analysis of the genomic sequence around the T-DNA insertion site, we discovered an ORF encoding 53 amino acid residues and named it At2g3698x. At2g3698x in K346 expressed at a higher level than in wild type, suggesting that over-expression of At2g3698x is responsible to K346 phenotype.
