Violaxanthin de-epoxidase (VDE) is the key enzyme in the xanthophyll cycle and protects plant photosynthetic apparatus from the damage of excessive light. A wheat (Triticum aestivum L cv. Xiaoyan 54) VDE cDNA was obta...Violaxanthin de-epoxidase (VDE) is the key enzyme in the xanthophyll cycle and protects plant photosynthetic apparatus from the damage of excessive light. A wheat (Triticum aestivum L cv. Xiaoyan 54) VDE cDNA was obtained using RT-PCR method. Its deduced protein sequence shares high identity with that of Arabidopsis and rice. Southern blot revealed that there are three copies of VDE gene per haploid genome of wheat. VDE transcript levels were higher in green leaf than in root, seed and etiolated leaf. Northern blotting analysis indicated that VDE mRNA level is induced during greening process of etiolated wheat seedling and increased by intense light illumination.展开更多
When plants absorb more light than that can be used for photosynthesis, the excessive energy can cause photoinhibition and even photooxidation of photosynthetic apparatus. Xanthophyll cycle-dependent photo-protection ...When plants absorb more light than that can be used for photosynthesis, the excessive energy can cause photoinhibition and even photooxidation of photosynthetic apparatus. Xanthophyll cycle-dependent photo-protection is believed to be the main mechanism for plants to deal with excessive light energy. This review focuses on molecular biological aspects and regulations of violaxanthin de-epoxidase and zeaxanthin epoxidase involved in xanthophyll cycle. We will summarize the functions of xanthophyll cycle, especially recent advances in its thermal dissipation mechanism of photoprotection. Some interesting issues deserving further study will be discussed.展开更多
Light is a fundamental source of energy but is also potentially harmful to organisms. Plants have evolved a variety of regulatory mechanisms to respond to the naturally varying light conditions. Xanthophyll cycle is n...Light is a fundamental source of energy but is also potentially harmful to organisms. Plants have evolved a variety of regulatory mechanisms to respond to the naturally varying light conditions. Xanthophyll cycle is now recognized as a key regulator and photoprotective mechanism found ubiquitously in plants. Xanthophyll cycle has multiple functions, such as thermal dissipation, protection against oxidative stress caused by light, modulation of the structure of thylakoid membrane, involving in blue light signal transduction and regulating the synthesis ofABA （Abscisic acid）. VDE （Violaxanth de-epoxidase） and ZE （zeaxanth epoxidase）, are involved in xanthophyll cycle. This paper outlined the functions of xanthophylls cycle and its relative enzymes.展开更多
文摘Violaxanthin de-epoxidase (VDE) is the key enzyme in the xanthophyll cycle and protects plant photosynthetic apparatus from the damage of excessive light. A wheat (Triticum aestivum L cv. Xiaoyan 54) VDE cDNA was obtained using RT-PCR method. Its deduced protein sequence shares high identity with that of Arabidopsis and rice. Southern blot revealed that there are three copies of VDE gene per haploid genome of wheat. VDE transcript levels were higher in green leaf than in root, seed and etiolated leaf. Northern blotting analysis indicated that VDE mRNA level is induced during greening process of etiolated wheat seedling and increased by intense light illumination.
文摘When plants absorb more light than that can be used for photosynthesis, the excessive energy can cause photoinhibition and even photooxidation of photosynthetic apparatus. Xanthophyll cycle-dependent photo-protection is believed to be the main mechanism for plants to deal with excessive light energy. This review focuses on molecular biological aspects and regulations of violaxanthin de-epoxidase and zeaxanthin epoxidase involved in xanthophyll cycle. We will summarize the functions of xanthophyll cycle, especially recent advances in its thermal dissipation mechanism of photoprotection. Some interesting issues deserving further study will be discussed.
文摘Light is a fundamental source of energy but is also potentially harmful to organisms. Plants have evolved a variety of regulatory mechanisms to respond to the naturally varying light conditions. Xanthophyll cycle is now recognized as a key regulator and photoprotective mechanism found ubiquitously in plants. Xanthophyll cycle has multiple functions, such as thermal dissipation, protection against oxidative stress caused by light, modulation of the structure of thylakoid membrane, involving in blue light signal transduction and regulating the synthesis ofABA （Abscisic acid）. VDE （Violaxanth de-epoxidase） and ZE （zeaxanth epoxidase）, are involved in xanthophyll cycle. This paper outlined the functions of xanthophylls cycle and its relative enzymes.
