Arabidopsis CPR5 is a senescence-regulatory gene with pleiotropic functions as predicted by the evolutionary theory of senescence
Arabidopsis CPR5 is a senescence-regulatory gene with pleiotropic functions as predicted by the evolutionary theory of senescence
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DOI：
10.1093/jxb/erm237
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发表时间：
2007-11-01
影响因子：
6.9
通讯作者：
Dijkwel, Paul P.
中科院分区：
文献类型：
--
作者：
Jing, Hai-Chun;Anderson, Lisa;Dijkwel, Paul P.
衰老的进化理论预测具有多效性功能的基因对于衰老调控非常重要。在植物中，没有直接的分子遗传学测试来证明这种衰老调节基因的存在。拟南芥cpr5突变体表现出多种表型，包括对各种信号分子过敏、病原体相关基因的组成型表达、异常毛状体发育、自发病变形成和加速叶片衰老。这些表明CPR5是控制拟南芥生命周期多个方面的有益基因。 CPR5 的异位表达恢复了所有突变表型。然而，在CPR5转录本增加的转基因植物中，在分离的叶子和发芽后约50天的后期发育中观察到叶子加速衰老，如衰老相关的生理和分子标记的较早出现所说明的。因此，CPR5通过抑制细胞死亡和确保正常植物发育对生命早期产生有益影响，但通过促进发育衰老对晚年产生有害影响。因此，正如衰老进化理论所预测的那样，CPR5 似乎具有典型的衰老调节基因的功能。
Evolutionary theories of senescence predict that genes with pleiotropic functions are important for senescence regulation. In plants there is no direct molecular genetic test for the existence of such senescence-regulatory genes. Arabidopsis cpr5 mutants exhibit multiple phenotypes including hypersensitivity to various signalling molecules, constitutive expression of pathogen-related genes, abnormal trichome development, spontaneous lesion formation, and accelerated leaf senescence. These indicate that CPR5 is a beneficial gene which controls multiple facets of the Arabidopsis life cycle. Ectopic expression of CPR5 restored all the mutant phenotypes. However, in transgenic plants with increased CPR5 transcripts, accelerated leaf senescence was observed in detached leaves and at late development around 50 d after germination, as illustrated by the earlier onset of senescence-associated physiological and molecular markers. Thus, CPR5 has early-life beneficial effects by repressing cell death and insuring normal plant development, but late-life deleterious effects by promoting developmental senescence. As such, CPR5 appears to function as a typical senescence-regulatory gene as predicted by the evolutionary theories of senescence.