Fig. 4.

Cloning of ONI2. (A) The ONI2 locus on chromosome 10. Mapping with 233 F₂ plants narrowed down the ONI2 locus to within a 94 kb region between marker 1429.8 and marker1420.4 near the centromere. In this region, 15 genes were predicted, one of which, Os10g0416200 marked in red, encodes a protein similar to fatty acid elongase. Os10g0416200 had mutations in two oni2 mutant alleles examined. (B) Complementation of oni2 by the fatty acid elongase gene Os10g0416200. The oni2-1 mutant calli transformed with the wild-type genomic fragment (left) showed regeneration of wild-type shoots, whereas the mutant calli transformed with an empty vector showed regeneration of mutant shoots (right). Bars = 1 cm. (C) A phylogenetic tree of fatty acid elongases of rice and Arabidopsis drawn on the basis of the entire amino acid sequences. Rice and Arabidopsis proteins are underlined in red and blue, respectively. ONI2 is shaded in yellow. AT1G01120, KCS1; AT1G04220, KCS2; AT1G68530, CUT1; AT2G26250, FDH; AT4G34520, FAE1.