水稻剑叶突变体的表型及T-DNA旁邻基因分析

从已构建的水稻（Oryza sativa L.）T-DNA插入突变体中鉴定获得一株穗部额外发育出叶片的突变体，并根据该叶片的形态学位置将其命名为剑叶突变体（J4）。研究表明这种额外发育的叶片呈现明显的缺陷，主要表现为叶片短小、表皮细胞变小、叶片中维管束数目减少等。进一步通过TAIL-PCR和inverse-PCR的方法克隆该突变体中T-DNA插入位置的旁邻序列，从而准确地将T-DNA定位到2号染色体上。基因表达分析显示，T-DNA插入位置附近的AK100376基因在J4突变体以及表型类似突变体neck leaf 1中的表达均被明显下调，可初步将其确定为与剑叶突变体表型相关的候选基因。

Phenotypic analysis of a rice flag leaf mutant and T-DNA flanking genes

We identified a mutant with extra leaves at the nodes of the panicle from a T-DNA insertion population constructed in our lab, and morphologically named it as a flag leaf mutant (J4 mutant). Analysis revealed that the extra leaves were abnormally developed, with short leaf blades, shortened epidemical cell lengths, and decreased numbers of vascular bundles in the leaf blade. Using TAIL-PCR and inverse-PCR analysis, we cloned the T-DNA flanking sequence in this mutant and accurately located the inserted T-DNA onto chromosome 2. Gene expression analysis revealed that AK100376, a T-DNA flanking gene, was obviously downregulated in both the J4 mutant and similar phenotype mutant neck leaf 1. Thus, AK100376 might be a candidate gene related to the phenotype in the J4 mutant. Here, we identified a flag leaf mutant and determined the phenotype-related candidate gene through expression analysis of the T-DNA flanking genes.