Journal of Integrative Agriculture ›› 2014, Vol. 13 ›› Issue (6): 1206-1215.DOI: 10.1016/S2095-3119(13)60604-8

• 论文 • 上一篇    下一篇

Wheat PROTON GRADIENT REGULATION 5 is Involved in Tolerance to Photoinhibition

 WANG Yuan-ge, HE Xue, MA Wen-ying, ZHAO Xue-qiang, LI Bin , TONG Yi-ping   

  1. The State Key Laboratory for Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, P.R.China
  • 收稿日期:2013-04-09 出版日期:2014-06-01 发布日期:2014-06-06
  • 通讯作者: TONG Yi-ping, Tel: +86-10-64806556, Fax: +86-10-64807609, E-mail: yptong@genetics.ac.cn
  • 基金资助:

    This research was supported by the National Basic Research Program of China (2009CB118302 and 2011CB100304).

Wheat PROTON GRADIENT REGULATION 5 is Involved in Tolerance to Photoinhibition

 WANG Yuan-ge, HE Xue, MA Wen-ying, ZHAO Xue-qiang, LI Bin , TONG Yi-ping   

  1. The State Key Laboratory for Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, P.R.China
  • Received:2013-04-09 Online:2014-06-01 Published:2014-06-06
  • Contact: TONG Yi-ping, Tel: +86-10-64806556, Fax: +86-10-64807609, E-mail: yptong@genetics.ac.cn
  • Supported by:

    This research was supported by the National Basic Research Program of China (2009CB118302 and 2011CB100304).

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摘要： Wheat (Triticum aestivum L.) often experiences photoinhibition due to strong light during the grain filling stage. As such, increasing the tolerance of wheat to photoinhibition is very desirable in breeding efforts focused on increasing grain yields. Previous reports have suggested that PROTON GRADIENT REGULATION 5 (PGR5) plays a central role in the generation of a proton gradient across the thylakoid membrane (DpH) and in acclimation to high light intensity conditions. Three PGR5 homoeologues were isolated from wheat, and mapped onto chromosomes 7A, 7B and 7D, respectively. The TaPGR5s shared highly similar genomic sequences and gene structures. The transcripts of TaPGR5s were found to be abundantly expressed in the flag leaves, and were transiently up-regulated by treatment with high light. High light treatment inhibited the net photosynthetic rate (Pn) and the maximal quantum yield of photosystem II (Fv/Fm). Further, these inhibitions were more evident in the leaves with reduced expression of TaPGR5s achieved using virus-induced gene silencing methods. Moreover, reducing TaPGR5 expression impaired the induction of non-photochemical quenching (NPQ), which caused more severe cell membrane damage and lipid peroxidation in high light. Additionally, we observed that TaPGR5s transcripts were more abundantly expressed in the wheat genotypes with higher ms-delayed light emission (ms-DLE), a value reflecting transthylakoid DpH. These results suggested that TaPGR5s play important roles in the tolerance of wheat to photoinhibition.

关键词: wheat , TaPGR5 , high light stress , photoinhibition , photosynthesis

Abstract: Wheat (Triticum aestivum L.) often experiences photoinhibition due to strong light during the grain filling stage. As such, increasing the tolerance of wheat to photoinhibition is very desirable in breeding efforts focused on increasing grain yields. Previous reports have suggested that PROTON GRADIENT REGULATION 5 (PGR5) plays a central role in the generation of a proton gradient across the thylakoid membrane (DpH) and in acclimation to high light intensity conditions. Three PGR5 homoeologues were isolated from wheat, and mapped onto chromosomes 7A, 7B and 7D, respectively. The TaPGR5s shared highly similar genomic sequences and gene structures. The transcripts of TaPGR5s were found to be abundantly expressed in the flag leaves, and were transiently up-regulated by treatment with high light. High light treatment inhibited the net photosynthetic rate (Pn) and the maximal quantum yield of photosystem II (Fv/Fm). Further, these inhibitions were more evident in the leaves with reduced expression of TaPGR5s achieved using virus-induced gene silencing methods. Moreover, reducing TaPGR5 expression impaired the induction of non-photochemical quenching (NPQ), which caused more severe cell membrane damage and lipid peroxidation in high light. Additionally, we observed that TaPGR5s transcripts were more abundantly expressed in the wheat genotypes with higher ms-delayed light emission (ms-DLE), a value reflecting transthylakoid DpH. These results suggested that TaPGR5s play important roles in the tolerance of wheat to photoinhibition.

Key words: wheat , TaPGR5 , high light stress , photoinhibition , photosynthesis