The Library
Protein diffusion and macromolecular crowding in thylakoid membranes
Tools
Kirchhoff, Helmut, Haferkamp, Silvia, Allen, John F., Epstein, D. B. A. and Mullineaux, Conrad W. (2008) Protein diffusion and macromolecular crowding in thylakoid membranes. Plant Physiology, Volume 146 (Number 4). pp. 1571-1578. doi:10.1104/pp.107.115170 ISSN 0032-0889.
Research output not available from this repository.
Request-a-Copy directly from author or use local Library Get it For Me service.
Official URL: http://dx.doi.org/10.1104/pp.107.115170
Abstract
The photosynthetic light reactions of green plants are mediated by chlorophyll-binding protein complexes located in the thylakoid membranes within the chloroplasts. Thylakoid membranes have a complex structure, with lateral segregation of protein complexes into distinct membrane regions known as the grana and the stroma lamellae. It has long been clear that some protein complexes can diffuse between the grana and the stroma lamellae, and that this movement is important for processes including membrane biogenesis, regulation of light harvesting, and turnover and repair of the photosynthetic complexes. In the grana membranes, diffusion may be problematic because the protein complexes are very densely packed (approximately 75% area occupation) and semicrystalline protein arrays are often observed. To date, direct measurements of protein diffusion in green plant thylakoids have been lacking. We have developed a form of fluorescence recovery after photobleaching that allows direct measurement of the diffusion of chlorophyll-protein complexes in isolated grana membranes from Spinacia oleracea. We show that about 75% of fluorophores are immobile within our measuring period of a few minutes. We suggest that this immobility is due to a protein network covering a whole grana disc. However, the remaining fraction is surprisingly mobile (diffusion coefficient 4.6 +/- 0.4 x 10(-11) cm(2) s(-1)), which suggests that it is associated with mobile proteins that exchange between the grana and stroma lamellae within a few seconds. Manipulation of the protein-lipid ratio and the ionic strength of the buffer reveals the roles of macromolecular crowding and protein-protein interactions in restricting the mobility of grana proteins.
Item Type: | Journal Article | ||||
---|---|---|---|---|---|
Subjects: | Q Science > QK Botany Q Science > QP Physiology |
||||
Divisions: | Faculty of Science, Engineering and Medicine > Science > Mathematics | ||||
Library of Congress Subject Headings (LCSH): | Thylakoids, Proteins, Diffusion, Macromolecules | ||||
Journal or Publication Title: | Plant Physiology | ||||
Publisher: | American Society of Plant Biologists | ||||
ISSN: | 0032-0889 | ||||
Official Date: | April 2008 | ||||
Dates: |
|
||||
Volume: | Volume 146 | ||||
Number: | Number 4 | ||||
Number of Pages: | 8 | ||||
Page Range: | pp. 1571-1578 | ||||
DOI: | 10.1104/pp.107.115170 | ||||
Status: | Peer Reviewed | ||||
Publication Status: | Published | ||||
Access rights to Published version: | Restricted or Subscription Access | ||||
Funder: | Deutsche Forschungsgemeinschaft (DFG), Royal Society (Great Britain), Biotechnology and Biological Sciences Research Council (Great Britain), Wellcome Trust (London, England), Leverhulme Trust (LT) |
Data sourced from Thomson Reuters' Web of Knowledge
Request changes or add full text files to a record
Repository staff actions (login required)
View Item |