水稻转座子对低能离子束辐照反应研究

The Research of Transposable Element in Rice Reaction to Low-energy Ion Beam Bombardment

用不同注量的低能N+离子束辐照水稻种子并培养发芽,根据培养7 d时发芽率、苗高和根长的结果,将辐照后的材料分为非生长抑制组(NGI)和生长抑制组(GI).为探讨水稻应答N+离子束辐照过程中转座子的转录强度,用RNA-seq技术对对照组、NGI组和GI组培养3 d的水稻芽体总RNA进行高通量转录组测序,根据水稻基因组比对、表达量的分析及基因功能注释的结果显示:共检测到水稻转录本36 382种,其中3组样品中检测到1 655种TEs有表达,对照、NGI、GI组样品中表达的TEs种类分别为972,818,1 271.由此可知生长抑制的样品中表达的转座因子最多(比对照多299种),说明一定剂量的低能离子束辐照能够促进转座子的转录,增强转座潜能,增加染色体结构改变的可能性,这可能是低能离子束诱变植物的机制之一.

The rice seeds irradiated by low-energy N ＋ ion beam were cultured to germinate, then for sev- en days. They were divided into the non-inhibition growth group （NGI： 1,2 × 1017 N ＋/cm2） and inhibi- tion growth group （GI： 6,8 × 1017 N ＋/cm2） according to the germination percentage, height of seedling and root long determination. For the purpose of exploring the functional gene expression of transposable elements （TEs） in rice responding to N ~ beam implantation, RNA-seq was used to analyze the total RNA from 3-day rice seedlings in the control, GI and NGI group. The results showed that total 36 382 tran- scripticns were obtained in the sequencing data, which included 11 851 known rice transposon. It was 972, 818 and 1 271 genes of TEs expressed in control, NGI and GI group respectively as 1 655 types of TEs expression in total were detected in the samples. These findings indicated that a certain dose of low- energy ion beam irradiation could promote transcription of transposons, enhance transpositional potential and increase chromosomal structural changes. This may be one mechanism of plant mutants induced by low energy ion beam.