umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Light induced changes in protein expression and uniform regulation of transcription in the thylakoid lumen of Arabidopsis thaliana
Umeå University, Faculty of Science and Technology, Department of Chemistry.
Umeå University, Faculty of Science and Technology, Department of Chemistry.
Umeå University, Faculty of Science and Technology, Department of Chemistry.
Umeå University, Faculty of Science and Technology, Department of Chemistry. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
2009 (English)In: PLoS ONE, ISSN 1932-6203, Vol. 4, no 5, e5649- p.Article in journal (Refereed) Published
Abstract [en]

In plants oxygenic photosynthesis is performed by large protein complexes found in the thylakoid membranes of chloroplasts. The soluble thylakoid lumen space is a narrow and compressed region within the thylakoid membrane which contains 80-200 proteins. Because the thylakoid lumen proteins are in close proximity to the protein complexes of photosynthesis, it is reasonable to assume that the lumen proteins are highly influenced by the presence of light. To identify light regulated proteins in the thylakoid lumen of Arabidopsis thaliana we developed a faster thylakoid preparation and combined this with difference gel electrophoresis (DIGE) of dark-adapted and light-adapted lumen proteomes. The DIGE experiments revealed that 19 lumen proteins exhibit increased relative protein levels after eight hour light exposure. Among the proteins showing increased abundance were the PsbP and PsbQ subunits of Photosystem II, major plastocyanin and several other proteins of known or unknown function. In addition, co-expression analysis of publicly available transcriptomic data showed that the co-regulation of lumen protein expression is not limited to light but rather that lumen protein genes exhibit a high uniformity of expression. The large proportion of thylakoid lumen proteins displaying increased abundance in light-adapted plants, taken together with the observed uniform regulation of transcription, implies that the majority of thylakoid lumen proteins have functions that are related to photosynthetic activity. This is the first time that an analysis of the differences in protein level during a normal day/night cycle has been performed and it shows that even a normal cycle of light significantly influences the thylakoid lumen proteome. In this study we also show for the first time, using co-expression analysis, that the prevalent lumenal chloroplast proteins are very similarly regulated at the level of transcription.

Place, publisher, year, edition, pages
2009. Vol. 4, no 5, e5649- p.
National Category
Biological Sciences
Identifiers
URN: urn:nbn:se:umu:diva-23163DOI: 10.1371/journal.pone.0005649PubMedID: 19461964OAI: oai:DiVA.org:umu-23163DiVA: diva2:220737
Available from: 2009-06-02 Created: 2009-06-02 Last updated: 2012-08-30Bibliographically approved
In thesis
1. The chloroplast lumen: New insights into thiol redox regulation and functions of lumenal proteins
Open this publication in new window or tab >>The chloroplast lumen: New insights into thiol redox regulation and functions of lumenal proteins
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

In higher plants oxygenic photosynthesis primarily takes place in the chloroplasts of leaves. Within the chloroplasts is an intricate membrane system, the thylakoid membrane, which is the site of light harvesting and photosynthetic electron transport. Enclosed by this membrane is the lumen space, which initially was believed to only contain a few proteins, but now is known to house a distinct set of >50 proteins, many for which there is still no proposed function. The work presented in this thesis is focused on understanding the functions of the proteins in the lumen space. Using proteomic methods, we investigated first the regulation of lumenal proteins by light and secondly by dithiol-disulphide exchange, mediated by the disulphide reductase protein thioredoxin. We furthermore performed structural and functional studies of the lumenal pentapeptide repeat proteins and of the PsbP-domain protein PPD6. When studying the diurnal expression pattern of the lumen proteins, using difference gel electrophoresis, we observed an increased abundance of fifteen lumen protein in light-adapted Arabidopsis thaliana plants. Among these proteins were subunits of the oxygen evolving complex, plastocyanin and proteins of unknown function. In our analysis of putative lumenal targets of thioredoxin, we identified nineteen proteins, constituting more than 40 % of the lumen proteins observable by our methods. A subset of these putative target proteins were selected for further studies, including structure determination by x-ray crystallography. The crystal structure of the pentapeptide repeat protein TL15 was solved to 1.3 Å resolution and further biochemical characterization suggested that it may function as a novel type of redox regulated molecular chaperone in the lumen. PPD6, a member of the PsbP-family of proteins, which is unique in that it possesses a conserved disulphide bond not found in any other PsbP-family protein, was also expressed, purified and crystallized. A preliminary x-ray analysis suggests that PPD6 exists as a dimer in the crystalline state and binds zinc ions. The high representation of targets of thioredoxin among the lumen proteins, along with the characterization of the pentapeptide repeat protein family, implies that dithiol-disulphide exchange reactions play an important role in the thylakoid lumen of higher plants, regulating processes such as photoprotection, protein turnover and protein folding.

Place, publisher, year, edition, pages
Umeå: Umeå universitet, 2012. 65 p.
Keyword
Photosynthesis, thylakoid lumen, thioredoxin, pentapeptide repeat, proteomics
National Category
Biochemistry and Molecular Biology
Research subject
Biochemistry
Identifiers
urn:nbn:se:umu:diva-58423 (URN)978-91-7459-467-6 (ISBN)
Public defence
2012-09-21, KBC huset, KB3B1, Umeå Universitet, Umeå, 09:00 (English)
Opponent
Supervisors
Available from: 2012-08-31 Created: 2012-08-29 Last updated: 2012-08-30Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed

Authority records BETA

Granlund, IreneHall, MichaelKieselbach, ThomasSchröder, Wolfgang P

Search in DiVA

By author/editor
Granlund, IreneHall, MichaelKieselbach, ThomasSchröder, Wolfgang P
By organisation
Department of ChemistryUmeå Plant Science Centre (UPSC)
In the same journal
PLoS ONE
Biological Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 136 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf