Increased Sensitivity of Photosynthesis to Antimycin A Induced by Inactivation of the Chloroplast ndhB Gene. Evidence for a Participation of the NADH-Dehydrogenase Complex to Cyclic Electron Flow around Photosystem I

AbstractIn plants, inactivation of either of the thylakoid proteins PGR5 and PGRL1 impairs cyclic electron flow (CEF) around photosystem I. Because PGR5 is unstable in the absence of the redox-active PGRL1, but not vice versa, PGRL1 is thought to be essential for CEF. However, we show here that inactivation of PGRL2, a distant homolog of PGRL1, relieves the need for PGRL1 itself. Conversely, high levels of PGRL2 destabilize PGR5 even when PGRL1 is present. In the absence of both PGRL1 and PGRL2, PGR5 alters thylakoid electron flow and impairs plant growth. Consequently, PGR5 can operate in CEF on its own, and is the target of the CEF inhibitor antimycin A, but its activity must be modulated by PGRL1. We conclude that PGRL1 channels PGR5 activity, and that PGRL2 triggers the degradation of PGR5 when the latter cannot productively interact with PGRL1.

Download Full-text

Redox regulation of the antimycin A sensitive pathway of cyclic electron flow around photosystem I in higher plant thylakoids

Biochimica et Biophysica Acta (BBA) - Bioenergetics ◽

10.1016/j.bbabio.2015.07.012 ◽

2016 ◽

Vol 1857 (1) ◽

pp. 1-6 ◽

Cited By ~ 32

Author(s):

Deserah D. Strand ◽

Nicholas Fisher ◽

Geoffry A. Davis ◽

David M. Kramer

Keyword(s):

Photosystem I ◽

Redox Regulation ◽

Electron Flow ◽

Cyclic Electron Flow ◽

Antimycin A ◽

Higher Plant

Download Full-text

Open Reading Frame ssr2016 is Required for Antimycin A-sensitive Photosystem I-driven Cyclic Electron Flow in the Cyanobacterium Synechocystis sp. PCC 6803

Plant and Cell Physiology ◽

10.1093/pcp/pci147 ◽

2005 ◽

Vol 46 (8) ◽

pp. 1433-1436 ◽

Cited By ~ 72

Author(s):

Nataliya Yeremenko ◽

Robert Jeanjean ◽

Peerada Prommeenate ◽

Vladimir Krasikov ◽

Peter J. Nixon ◽

...

Keyword(s):

Photosystem I ◽

Electron Flow ◽

Cyclic Electron Flow ◽

Open Reading Frame ◽

Antimycin A ◽

Reading Frame ◽

Synechocystis Sp ◽

Pcc 6803

Download Full-text

Photosystem I cyclic electron flow via chloroplast NADH dehydrogenase-like complex performs a physiological role for photosynthesis at low light

Scientific Reports ◽

10.1038/srep13908 ◽

2015 ◽

Vol 5 (1) ◽

Cited By ~ 53

Author(s):

Wataru Yamori ◽

Toshiharu Shikanai ◽

Amane Makino

Keyword(s):

Electron Transport ◽

Light Intensity ◽

Photosystem I ◽

Nadh Dehydrogenase ◽

Physiological Function ◽

Electron Flow ◽

Cyclic Electron Flow ◽

Cyclic Electron Transport ◽

Low Light ◽

Ps I

Abstract Cyclic electron transport around photosystem I (PS I) was discovered more than a half-century ago and two pathways have been identified in angiosperms. Although substantial progress has been made in understanding the structure of the chloroplast NADH dehydrogenase-like (NDH) complex, which mediates one route of the cyclic electron transport pathways, its physiological function is not well understood. Most studies focused on the role of the NDH-dependent PS I cyclic electron transport in alleviation of oxidative damage in strong light. In contrast, here it is shown that impairment of NDH-dependent cyclic electron flow in rice specifically causes a reduction in the electron transport rate through PS I (ETR I) at low light intensity with a concomitant reduction in CO2 assimilation rate, plant biomass and importantly, grain production. There was no effect on PS II function at low or high light intensity. We propose a significant physiological function for the chloroplast NDH at low light intensities commonly experienced during the reproductive and ripening stages of rice cultivation that have adverse effects crop yield.

Download Full-text