转基因水稻叶片外卷突变体的机理

Preliminary investigation on outward rolled leaf mutant of transgenic rice

以水稻品种明恢86和明恢86转基因水稻正常叶植株为对照组进行研究,对叶片横截面组织结构的观察发现,单位面积突变体外卷叶片的上表皮泡状细胞数量增加,推测外卷是由于泡状细胞数量增加引起的.遗传分析结果显示,该卷叶突变性状是由隐性单基因突变引起的.外源基因在卷叶突变体中为单拷贝,并且外源基因与卷叶性状共分离,说明卷叶性状是T-DNA插入引起的.T-DNA插入位点分析结果显示插入位点位于水稻第9号染色体长臂上的非基因区,是一个新的与水稻卷叶相关的突变位点.

Outward rolling leaf is likely to improve light interception rate of rice. To investigate cytology and molecular mechanism of this trait, mutant plants 3α-HSD with stable traits of outward rolling leaf were used as the experimental group, with cultivated variety MH 86 and transgenic plants with flat leaves used as the control. Microscopic observation on cross section of leaves indicated that rolled leaf of mutant plants was caused by an increased number of bulliform cells. Genetic analysis showed that outward rolling leaf was attributed to the mutation of single recessive genes. This exogenous gene was a single copy in rolled leaf mutant, and co-segrega-ted with rolled leaf trait, indicating that rolled leaf trait was likely caused by T-DNA insertion. Furthermore, analysis of T-DNA in-sertion site showed that this insertion located in the non-coding region in long arm of chromosome 9, which was a new mutation site related to the mechanism of this trait, related to rice leaf rolling.