Publications

Authors:

Ballottari, Matteo; Truong, Thuy B; De Re, Eleonora; Erickson, Erika; Stella, Giulio Rocco; Fleming, Graham R; Bassi, Roberto; Niyogi, Krishna K.

Title:

Identification of pH-sensing Sites in the Light Harvesting Complex Stress-related 3 Protein Essential for Triggering Non-photochemical Quenching in Chlamydomonas reinhardtii

Year:

2016

Type of item:

Articolo in Rivista

Tipologia ANVUR:

Articolo su rivista

Language:

Inglese

Format:

A Stampa

Referee:

Sì

Name of journal:

JBC

ISSN of journal:

0021-9258

N° Volume:

291

Number or Folder:

14

Page numbers:

7334-7346

Keyword:

fluorescence; non-photochemical quenching; photoprotection; photosynthesis; photosynthetic pigment; photosystem II; plant biochemistry; Chlamydomonas reinhardtii; Hydrogen-Ion Concentration; Light-Harvesting Protein Complexes; Mutagenesis, Site-Directed; Mutation, Missense; Thylakoids

Short description of contents:

Light harvesting complex stress-related 3 (LHCSR3) is the protein essential for photoprotective excess energy dissipation (non-photochemical quenching, NPQ) in the model green algaChlamydomonas reinhardtii Activation of NPQ requires low pH in the thylakoid lumen, which is induced in excess light conditions and sensed by lumen-exposed acidic residues. In this work we have used site-specific mutagenesisin vivoandin vitrofor identification of the residues in LHCSR3 that are responsible for sensing lumen pH. Lumen-exposed protonatable residues, aspartate and glutamate, were mutated to asparagine and glutamine, respectively. By expression in a mutant lacking all LHCSR isoforms, residues Asp(117), Glu(221), and Glu(224)were shown to be essential for LHCSR3-dependent NPQ induction inC. reinhardtii Analysis of recombinant proteins carrying the same mutations refoldedin vitrowith pigments showed that the capacity of responding to low pH by decreasing the fluorescence lifetime, present in the wild-type protein, was lost. Consistent with a role in pH sensing, the mutations led to a substantial reduction in binding the NPQ inhibitor dicyclohexylcarbodiimide.

Product ID:

94852

Handle IRIS:

11562/954290

Last Modified:

November 12, 2022

Bibliographic citation:

Ballottari, Matteo; Truong, Thuy B; De Re, Eleonora; Erickson, Erika; Stella, Giulio Rocco; Fleming, Graham R; Bassi, Roberto; Niyogi, Krishna K., Identification of pH-sensing Sites in the Light Harvesting Complex Stress-related 3 Protein Essential for Triggering Non-photochemical Quenching in Chlamydomonas reinhardtii «JBC» , vol. 291 , n. 14 , 2016 , pp. 7334-7346

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