liu.seSök publikationer i DiVA
Ändra sökning
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
A Protein Phosphorylation Threshold for Functional Stacking of Plant Photosynthetic Membranes
Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet.
Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
2010 (Engelska)Ingår i: PLOS ONE, ISSN 1932-6203, Vol. 5, nr 6Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Phosphorylation of photosystem II (PSII) proteins affects macroscopic structure of thylakoid photosynthetic membranes in chloroplasts of the model plant Arabidopsis. In this study, light-scattering spectroscopy revealed that stacking of thylakoids isolated from wild type Arabidopsis and the mutant lacking STN7 protein kinase was highly influenced by cation (Mg++) concentrations. The stacking of thylakoids from the stn8 and stn7stn8 mutants, deficient in STN8 kinase and consequently in light-dependent phosphorylation of PSII, was increased even in the absence of Mg++. Additional PSII protein phosphorylation in wild type plants exposed to high light enhanced Mg++-dependence of thylakoid stacking. Protein phosphorylation in the plant leaves was analyzed during day, night and prolonged darkness using three independent techniques: immunoblotting with anti-phosphothreonine antibodies; Diamond ProQ phosphoprotein staining; and quantitative mass spectrometry of peptides released from the thylakoid membranes by trypsin. All assays revealed dark/night-induced increase in phosphorylation of the 43 kDa chlorophyll-binding protein CP43, which compensated for decrease in phosphorylation of the other PSII proteins in wild type and stn7, but not in the stn8 and stn7stn8 mutants. Quantitative mass spectrometry determined that every PSII in wild type and stn7 contained on average 2.5 +/- 0.1 or 1.4 +/- 0.1 phosphoryl groups during day or night, correspondingly, while less than every second PSII had a phosphoryl group in stn8 and stn7stn8. It is postulated that functional cation-dependent stacking of plant thylakoid membranes requires at least one phosphoryl group per PSII, and increased phosphorylation of PSII in plants exposed to high light enhances stacking dynamics of the photosynthetic membranes.

Ort, förlag, år, upplaga, sidor
Public Library of Science (PLoS) , 2010. Vol. 5, nr 6
Nationell ämneskategori
Medicin och hälsovetenskap
Identifikatorer
URN: urn:nbn:se:liu:diva-57385DOI: 10.1371/journal.pone.0010963ISI: 000278380500009OAI: oai:DiVA.org:liu-57385DiVA, id: diva2:325571
Anmärkning
Original Publication: Rikard Fristedt, Pontus Granath and Alexander Vener, A Protein Phosphorylation Threshold for Functional Stacking of Plant Photosynthetic Membranes, 2010, PLOS ONE, (5), 6. http://dx.doi.org/10.1371/journal.pone.0010963 Copyright: Public Library of Science (PLoS) http://www.plos.org/ Tillgänglig från: 2010-06-18 Skapad: 2010-06-18 Senast uppdaterad: 2010-11-26
Ingår i avhandling
1. Regulatory Functions of Protein Phosphorylation in Plant Photosynthetic Membranes
Öppna denna publikation i ny flik eller fönster >>Regulatory Functions of Protein Phosphorylation in Plant Photosynthetic Membranes
2010 (Engelska)Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
Abstract [en]

Oxygenic photosynthesis is the process in plants, algae and cyanobacteria which converts light energy from the sun into carbohydrates and at the same time produces oxygen from water. Both carbohydrates and oxygen are essential to sustain life on earth. Sunlight is thus a necessity for life, but it can also cause severe problems for photosynthetic organisms, which have evolved several remarkable acclimation systems to cope with light fluctuations in the environment. In higher plants the light driven reactions of photosynthesis proceed in the chloroplast thylakoid membranes highly organized into stacked regions of grana and interconnecting stroma  lamellae. The grana structure is thought to provide functional benefits in the processes of acclimation of the photosynthetic apparatus, particularly in the quality control of photosystem II (PSII) were photodamaged PSII is repaired in a stepwise manner. These processes in the thylakoid membranes were suggested to be regulated by reversible phosphorylation of several proteins in PSII and in its light harvesting antennae complexes (LHCII). Two thylakoid protein kinases, called STN8 and STN7, have been previously identified as responsible for the phosphorylation of PSII and LHCII, respectively. However, molecular mechanisms and the exact functions of these protein phosphorylation events remained largely unknown.

In this thesis research I have demonstrated that the PSII protein phosphorylation is needed for the maintenance of the thylakoid structure in Arabidopsis thaliana chloroplasts. A big part of the work on characterization of proteins and their phosphorylation has been done using novel mass spectrometry techniques, and we further developed a label-free method for quantitative studies of protein phosphorylation. The phosphorylation of PSII proteins was found to be diurnal regulated and required for maintenance of the cation-dependent functional stacking of the thylakoid membranes. This phosphorylation was further shown to be important for the regulated turnover of the D1 protein of PSII.

Phosphorylation of the plant specific TSP9 protein was found to be dependent on STN7 kinase, and plants deficient in TSP9 showed reduced ability to perform the photosynthetic state transitions and to execute thermal dissipation of excess light energy under high light conditions. I also accomplished characterization of the protein phosphorylation in thylakoids from Arabidopsis plants subjected to high light treatment and discovered STN7-dependent phosphorylation of the antenna protein CP29 required for the adaptive disassembly of PSII supercomplexes in conditions of high light stress.

Ort, förlag, år, upplaga, sidor
Linköping: Linköping University Electronic Press, 2010. s. 42
Serie
Linköping University Medical Dissertations, ISSN 0345-0082 ; 1212
Nationell ämneskategori
Medicin och hälsovetenskap
Identifikatorer
urn:nbn:se:liu:diva-62303 (URN)978-91-7393-301-8 (ISBN)
Disputation
2010-12-17, Linden, Hälsouniversitetet, Campus US, Linköpings universitet, Linköping, 13:00 (Engelska)
Opponent
Handledare
Tillgänglig från: 2010-11-26 Skapad: 2010-11-26 Senast uppdaterad: 2020-02-26Bibliografiskt granskad

Open Access i DiVA

fulltext(1747 kB)275 nedladdningar
Filinformation
Filnamn FULLTEXT01.pdfFilstorlek 1747 kBChecksumma SHA-512
f619e5fbfeabf1aeca52259f297802a95a2b75e504ff41cb8b87fb83538bac4a8108e07e99fc4add7c7517d7f8a7e291449b885000fa65a69d55cbab7e86b90e
Typ fulltextMimetyp application/pdf

Övriga länkar

Förlagets fulltext

Personposter BETA

Fristedt, RikardVener, Alexander

Sök vidare i DiVA

Av författaren/redaktören
Fristedt, RikardVener, Alexander
Av organisationen
CellbiologiHälsouniversitetetInstitutionen för klinisk och experimentell medicin
Medicin och hälsovetenskap

Sök vidare utanför DiVA

GoogleGoogle Scholar
Totalt: 275 nedladdningar
Antalet nedladdningar är summan av nedladdningar för alla fulltexter. Det kan inkludera t.ex tidigare versioner som nu inte längre är tillgängliga.

doi
urn-nbn

Altmetricpoäng

doi
urn-nbn
Totalt: 216 träffar
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf