Control of the light harvesting function of chloroplast membranes: The LHCII-aggregation model for non-photochemical quenching

Edited by Peter Brzezinski

Received 28 June 2005; accepted 7 July 2005. published online 19 July 2005.

Abstract

Dissipation of excess excitation energy within the photosystem II light-harvesting antenna (LHCII) by non-photochemical quenching (NPQ) is an important photoprotective process in plants. An update to a hypothesis for the mechanism of NPQ [FEBS Letters 292, 1991] is presented. The impact of recent advances in understanding the structure, organisation and photophysics of LHCII is assessed. We show possible locations of the predicted regulatory and quenching pigment-binding sites in the structural model of the major LHCII. We suggest that NPQ is a highly regulated concerted response of the organised thylakoid macrostructure, which can include different mechanisms and sites at different times.

Keywords: Non-photochemical quenching, Light harvesting complex, Thylakoid membrane, Chlorophyll fluorescence, Xanthophyll cycle, Photoprotection

Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield S10 2TN, UK

Corresponding author. Fax: +44 114 222 2712.

PII: S0014-5793(05)00832-X

doi:10.1016/j.febslet.2005.07.003

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