Higher amounts of anthocyanins and UV-absorbing compounds effectively lowered CPD photorepair in purple rice (Oryza sativa L.)
Higher amounts of anthocyanins and UV-absorbing compounds effectively lowered CPD photorepair in purple rice (Oryza sativa L.)
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DOI：
10.1046/j.1365-3040.2003.01087.x
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发表时间：
2003-10-01
影响因子：
7.3
通讯作者：
Kumagai, T
中科院分区：
文献类型：
--
作者：
Hada, H;Hidema, J;Kumagai, T
以台中65（T-65）为遗传背景的水稻紫叶基因P1近等基因系（NIL）的生长受到紫外线-B辐射（UV-B）的显著抑制，尽管NIL中的紫外线吸收化合物和花色素苷的量显著高于T-65。为了了解类黄酮在T-65和近等基因系中对UV-B辐射损伤的保护作用，研究了（1）叶片中环丁烷嘧啶二聚体（CPD）稳态水平的变化与花色素苷和紫外吸收物质积累变化之间的关系，（2）叶片对CPD的敏感性和光修复CPD的能力。虽然补充UV-B提高了两个品系叶片中CPD的稳态水平，但在任何时候，NIL叶片中的CPD水平都高于T-65。短期（挑战）UV-B暴露的CPD诱导的敏感性低于在T-65的NIL。另一方面，CPD光修复也低于在那些在T-65的NIL的叶片。CPD-光修复的减少是由于降低了叶片穿透蓝/UV-A辐射，这是有效的光复活酶，花青素。因此，花青素和紫外线吸收化合物的积累没有有效地发挥作用，筛选对紫外线-B辐射升高造成的损害，在近红外线，和生长的阻滞，导致其光修复CPD的能力较低，较高量的花青素。
Growth of a near-isogenic line (NIL) for the purple leaf gene Pl of rice with a genetic background of Taichung 65 (T-65) rice was significantly retarded by supplementary ultraviolet-B radiation (UV-B), despite the fact that the amounts of UV-absorbing compounds and anthocyanins in NIL were significantly higher than those in T-65. In order to understand the role of flavonoids in UV-B induced damage protection in T-65 and the NIL, both the (1) relationships between changes in the steady state of cyclobutane pyrimidine dimer (CPD) levels and changes in accumulation of anthocyanins and UV-absorbing compounds in leaves with leaf age, and (2) the susceptibility to CPD induction by UV-B radiation and the ability to photorepair CPD were examined. Although supplementary UV-B elevated the steady state of CPD levels in leaves in both strains, the level in the leaf of the NIL was higher than that in T-65 at any time. The susceptibility to CPD induction by short-term (challenge) UV-B exposure was lower in the NIL than in T-65. On the other hand, the CPD photorepair was also lower in the leaves of the NIL than in those of T-65. The decrease in CPD-photorepair in the NIL was due to a lowering of the leaf-penetrating blue/UV-A radiation, which is effective for photoreactivation by photolyase, by anthocyanins. Thus, accumulation of anthocyanins and UV-absorbing compounds did not effectively function as screening against damage caused by elevated UV-B radiation in the NIL, and the retardation of growth in the NIL resulted from its lower ability to photorepair CPD by higher amounts of anthocyanins.