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Gene Review

NPQ4  -  photosystem II subunit S

Arabidopsis thaliana

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High impact information on NPQ4


Biological context of NPQ4


Anatomical context of NPQ4

  • We conclude that at least two major factors determine the quenching of chlorophyll fluorescence in Lhcb proteins, i.e., intrasubunit conformational change and intersubunit interactions within the lipid membranes, and that these processes are both important in the photoprotection mechanism of nonphotochemical quenching in vivo [8].
  • Nonphotochemical quenching (NPQ) of excitation energy, which protects higher plant photosynthetic machinery from photodamage, is triggered by acidification of the thylakoid lumen as a result of light-induced proton pumping, which also drives the synthesis of ATP [9].

Associations of NPQ4 with chemical compounds


Analytical, diagnostic and therapeutic context of NPQ4

  • Pulse-modulation fluorometry was employed to characterize one line (denoted Lsr1(-)) that exhibited an approximately 50% reduction in NPQ compared to the wild type (WT) [6].


  1. A pigment-binding protein essential for regulation of photosynthetic light harvesting. Li, X.P., Björkman, O., Shih, C., Grossman, A.R., Rosenquist, M., Jansson, S., Niyogi, K.K. Nature (2000) [Pubmed]
  2. Arabidopsis mutants define a central role for the xanthophyll cycle in the regulation of photosynthetic energy conversion. Niyogi, K.K., Grossman, A.R., Björkman, O. Plant Cell (1998) [Pubmed]
  3. A zeaxanthin-independent nonphotochemical quenching mechanism localized in the photosystem II core complex. Finazzi, G., Johnson, G.N., Dall'Osto, L., Dallosto, L., Joliot, P., Wollman, F.A., Bassi, R. Proc. Natl. Acad. Sci. U.S.A. (2004) [Pubmed]
  4. Molecular and global time-resolved analysis of a psbS gene dosage effect on pH- and xanthophyll cycle-dependent nonphotochemical quenching in photosystem II. Li, X.P., Gilmore, A.M., Niyogi, K.K. J. Biol. Chem. (2002) [Pubmed]
  5. The violaxanthin cycle protects plants from photooxidative damage by more than one mechanism. Havaux, M., Niyogi, K.K. Proc. Natl. Acad. Sci. U.S.A. (1999) [Pubmed]
  6. A nonphotochemical-quenching-deficient mutant of Arabidopsis thaliana possessing normal pigment composition and xanthophyll-cycle activity. Peterson, R.B., Havir, E.A. Planta (2000) [Pubmed]
  7. Photosynthetic properties of an Arabidopsis thaliana mutant possessing a defective PsbS gene. Peterson, R.B., Havir, E.A. Planta (2001) [Pubmed]
  8. Time-resolved fluorescence analysis of the photosystem II antenna proteins in detergent micelles and liposomes. Moya, I., Silvestri, M., Vallon, O., Cinque, G., Bassi, R. Biochemistry (2001) [Pubmed]
  9. In vivo modulation of nonphotochemical exciton quenching (NPQ) by regulation of the chloroplast ATP synthase. Kanazawa, A., Kramer, D.M. Proc. Natl. Acad. Sci. U.S.A. (2002) [Pubmed]
  10. Xanthophyll cycle-dependent nonphotochemical quenching in Photosystem II: Mechanistic insights gained from Arabidopsis thaliana L. mutants that lack violaxanthin deepoxidase activity and/or lutein. Gilmore, A.M. Photosyn. Res. (2001) [Pubmed]
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