Association of Ferredoxin:NADP+ oxidoreductase with the photosynthetic apparatus modulates electron transfer in Chlamydomonas reinhardtii

Safe and efficient conversion of solar energy to metabolic energy by plants is based on tightly inter-regulated transfer of excitation energy, electrons and protons in the photosynthetic machinery according to the availability of light energy, as well as the needs and restrictions of metabolism itself. Plants have mechanisms to enhance the capture of energy when light is limited for growth and development. Also, when energy is in excess, the photosynthetic machinery slows down the electron transfer reactions in order to prevent the production of reactive oxygen species and the consequent damage of the photosynthetic machinery. In this opinion paper, we present a partially hypothetical scheme describing how the photosynthetic machinery controls the flow of energy and electrons in order to enable the maintenance of photosynthetic activity in nature under continual fluctuations in white light intensity. We discuss the roles of light-harvesting II protein phosphorylation, thermal dissipation of excess energy and the control of electron transfer by cytochrome b 6 f , and the role of dynamically regulated turnover of photosystem II in the maintenance of the photosynthetic machinery. We present a new hypothesis suggesting that most of the regulation in the thylakoid membrane occurs in order to prevent oxidative damage of photosystem I.

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Photosynthetic apparatus organization and function in the wild type and a chlorophyll b -less mutant of Chlamydomonas reinhardtii . Dependence on carbon source

Planta ◽

10.1007/s004250000279 ◽

2000 ◽

Vol 211 (3) ◽

pp. 335-344 ◽

Cited By ~ 85

Author(s):

Juergen E. W. Polle ◽

John R. Benemann ◽

Ayumi Tanaka ◽

Anastasios Melis

Keyword(s):

Carbon Source ◽

Chlamydomonas Reinhardtii ◽

Photosynthetic Apparatus ◽

Chlorophyll B ◽

Wild Type ◽

In The Wild ◽

And Function

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RCD1 Coordinates Chloroplastic and Mitochondrial Electron Transfer through Interaction with ANAC Transcription Factors in Arabidopsis

10.1101/327411 ◽

2018 ◽

Cited By ~ 1

Author(s):

Alexey Shapiguzov ◽

Julia P. Vainonen ◽

Kerri Hunter ◽

Helena Tossavainen ◽

Arjun Tiwari ◽

...

Keyword(s):

Electron Transfer ◽

Transcription Factors ◽

Photosynthetic Apparatus ◽

Nuclear Gene ◽

Complex Iii ◽

Nuclear Gene Expression ◽

Mitochondrial Retrograde Signaling ◽

Thiol Redox State ◽

Thiol Redox

AbstractSignaling from chloroplasts and mitochondria, both dependent on reactive oxygen species (ROS), merge at the nuclear protein RADICAL-INDUCED CELL DEATH1 (RCD1). ROS produced in the chloroplasts affect the abundance, thiol redox state and oligomerization of RCD1. RCD1 directly interacts in vivo with ANAC013 and ANAC017 transcription factors, which are the mediators of the ROS-related mitochondrial complex III retrograde signa and suppresses activity of ANAC013 and ANAC017. Inactivation of RCD1 leads to increased expression of ANAC013 and ANAC017-regulated genes belonging to the mitochondrial dysfunction stimulon (MDS), including genes for mitochondrial alternative oxidases (AOXs). Accumulating AOXs and other MDS gene products alter electron transfer pathways in the chloroplasts, leading to diminished production of chloroplastic ROS and increased protection of photosynthetic apparatus from ROS damage. RCD1-dependent regulation affects chloroplastic and mitochondrial retrograde signaling including chloroplast signaling by 3’-phosphoadenosine 5’-phosphate (PAP). Sensitivity of RCD1 to organellar ROS provides feedback control of nuclear gene expression.

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