Genetic and biochemical analyzes of an accelerated internode overgrowth mutant in rice.

利用γ射线辐照水稻种子，从粳稻品种越光中诱导出一个水稻节间超生长突变体--阿波-大取（AO）。由一个隐性基因ao-1（accelerated internode overgrowth 1）表达的一对基因，在感染由赤霉菌引起的“恶苗病”的幼苗中表现出类似的细茎表型。本文报道了几种赤霉素及其阻滞剂配合施用对突变体幼苗的反应性试验结果，用AO（ao-1）× Kotake-tamanishiki（d-18）和AO（ao-1）× Tangin-bozu（d-35）两个杂交组合进行双突变体分析对突变体地上部糖组分的分析结果表明，突变体地上部半纤维素I和纤维素组分中的糖含量比Koshi-hikari显著增加，AO突变体和Koshi-hikari的地上部可溶性蛋白和细胞壁蛋白的二维分析结果表明，突变体地上部可溶性蛋白和细胞壁蛋白的含量比Koshi-hikari的高，而半纤维素I和纤维素组分中的糖含量比Koshi-hikari的高。hikari分析结果表明，突变体中的一些特异性蛋白质点在2D-PAGEs.205测序的克隆在从AO茎伸长节间提取的mRNA中分离的cDNA文库中进行了与其它核苷酸序列的同源性研究使用Blaissance电子邮件服务器（NCBI）的DNA数据库和DNASIS-MAC（日立软件工程公司，Ltd.）。结果表明，其中41个克隆的氨基酸序列与数据库中的DNA序列有部分同源性（>40%），ao-1基因的克隆实验正在进行中。

A rice internode overgrowth mutant, awa-odori (AO) was induced from a japonica cultivar, Koshi-hikari by gamma-ray seed irradiation. The slender shoot phenotype alike in seedlings infected by "bakanae" disease caused by Gibberella fujikuroi has been expressed by a recessive gene named ao-1(accelerated internode overgrowth 1). The results of examination on responsibility of mutant seedlings to some combined applications of GA_3 and its retardant, Uniconazole suggested that this characteristics of the mutant is not caused by an over product of endogenous gibberellins as shown in "bakanae" disease.Double mutant analysis with two cross combinations of AO (ao-1) x Kotake-tamanishiki (d-18) and AO (ao-1) x Tangin-bozu(d-35) also supported this suggestion.The result of analysis on sugar components of shoot showed that sugar contents of hemicellulose I and cellulose fractions increased significantly in the mutant compared with Koshi-hikari.Two-dimensional analysis of soluble and cell wall proteins extracted from the basal area of seedling shoot of AO mutant and Koshi-hikari was carried out and some specific protein spots in the mutant were detected from both 2D-PAGEs.205 sequenced clones in the cDNA library isolated from mRNAs extracted from elongating internodes of AO shoot were researched on the homology to the other nuclertide sequences using DNA-database of Blastn E-mail Server (NCBI) and DNASIS-MAC (Hitachi Software Engineering Co., Ltd.). The result showed that 41 clones among them encoded a partial homology (>40% in the amino acid sequence level) to DNA sequences recorded in the databases.Further experiment for cloning ao-1 gene is now being continued.