Resistance of rice to ultraviolet-B radiation based on UVB-induced DNA lesions and their photorepairs

基于 UVB 诱导的 DNA 损伤及其光修复的水稻对 UV-B 辐射的抵抗力

基本信息

批准号：
10044195
负责人：
KUMAGAI Tadashi
金额：
$ 6.27万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10044195/
关键词：
UVB radiation DNA lesion Cyclobutyl pyrimidine dimer photolyase Photorepair Rice Resistance to UVB Sensitivity to UVB ミクロブタン型ピリミジンダイアー光修復酵素

项目摘要

1 Changes in DNA lesions during growth in rice: (1) We found that rice could be more susceptible to CPD induction at the stage when the second, third or fourth leaves are developing, and UVB sensitivity correlates with low CPD photorepair. (2) Dark-grown etiolated rice does not have any CPD photorepair ability, and the induction of CPD photorepair was shown to be controlled by phytochrome/cryptochrome photosystems. (3) It was evident that 2-3 CPDs/Mb. DNA is always being kept in rice growing in solar radiation.2 Cultivar differences in CPD photorepair between UV-resistant and -sensitive rice : We previously suggested that two possibilities might account for CPD photorepair defiviency in UV-sensitive rice (Norin 1). One is due to a structural mutation, which could affect the formation of CPD-photolyase complex, or dissociation of the complex. The other is due to mutation of regulatory mechanisms for induction of photolyase, which could decrease the levels of photolyase. Based on the single light-pulse method and temperature dependence, we have proved that a structural mutation might be involved in high UV-sensitivity in Norin 1.3 Effect of UVB radiation on protein contents in leaves : We previously suggested that Rubisco rather than LHCII might be more influenced by supplemental UVB radiation during growth. Therefore, we studied the effects of UVB radiation (1) on the synthesis and degradation of Rubisco and LHCII using ィイD115ィエD1N as a tracer, and (2) on the mRNA transcript levels for Rubisco subunits (rbcS encoded in nuclear and rbcL encoded in chloroplast) and LHCII (cab encoded in nuclear, in leaves of UV-resistant and -sensitive rice. We found that the expression of nuclear encoded genes were more influenced than that of chloroplast by UVB, and that the expression of rbcL was more influenced than cab by UVB.

1 水稻生长过程中 DNA 损伤的变化：(1) 我们发现水稻在第二、第三或第四叶发育阶段更容易受到 CPD 诱导，并且 UVB 敏感性与低 CPD 光修复相关 (2)。深色生长的黄化水稻不具有任何 CPD 光修复能力，并且 CPD 光修复的诱导被证明是由光敏色素/隐花色素光系统控制的 (3) 很明显 2-3。 CPDs/Mb. DNA 始终保留在太阳辐射下生长的水稻中。2 抗紫外线和敏感水稻之间 CPD 光修复的品种差异：我们之前提出两种可能性可能解释紫外线敏感水稻的 CPD 光修复缺陷（Norin） 1). 一种是由于结构突变，可能影响 CPD-光裂合酶复合物的形成或复合物的解离，另一种是由于诱导光裂合酶的调节机制的突变。基于单光脉冲方法和温度依赖性，我们已经证明结构突变可能与 Norin 1.3 UVB 辐射对叶片蛋白质含量的影响有关。 Rubisco 而不是 LHCII 在生长过程中可能更容易受到补充 UVB 辐射的影响，因此，我们利用 UVB 辐射 (1) 研究了 UVB 辐射对 Rubisco 和 LHCII 合成和降解的影响。 D115D1N 作为示踪剂，以及 (2) 在抗紫外线和敏感水稻叶片中 Rubisco 亚基（核中编码的 rbcS 和叶绿体中编码的 rbcL）和 LHCII（核中编码的 cab）的 mRNA 转录水平。我们发现UVB对核编码基因表达的影响大于叶绿体表达，UVB对rbcL表达的影响大于cab的影响。