The chloroplast-localized small heat shock protein Hsp21 associates with the thylakoid membranes in heat-stressed plants
Bernfur, Katja LU ; Rutsdottir, Gudrun LU and Emanuelsson, Cecilia LU
(2017)
In Protein Science
26(9).
p.1773-1784
- Abstract
The small heat shock protein (sHsp) chaperones are crucial for cell survival and can prevent aggregation of client proteins that partially unfold under destabilizing conditions. Most investigations on the chaperone activity of sHsps are based on a limited set of thermosensitive model substrate client proteins since the endogenous targets are often not known. There is a high diversity among sHsps with a single conserved β-sandwich fold domain defining the family, the α-crystallin domain, whereas the N-terminal and C-terminal regions are highly variable in length and sequence among various sHsps and conserved only within orthologues. The endogenous targets are probably also varying among various sHsps, cellular compartments, cell type and... (More)
The small heat shock protein (sHsp) chaperones are crucial for cell survival and can prevent aggregation of client proteins that partially unfold under destabilizing conditions. Most investigations on the chaperone activity of sHsps are based on a limited set of thermosensitive model substrate client proteins since the endogenous targets are often not known. There is a high diversity among sHsps with a single conserved β-sandwich fold domain defining the family, the α-crystallin domain, whereas the N-terminal and C-terminal regions are highly variable in length and sequence among various sHsps and conserved only within orthologues. The endogenous targets are probably also varying among various sHsps, cellular compartments, cell type and organism. Here we have investigated Hsp21, a non-metazoan sHsp expressed in the chloroplasts in green plants which experience huge environmental fluctuations not least in temperature. We describe how Hsp21 can also interact with the chloroplast thylakoid membranes, both when isolated thylakoid membranes are incubated with Hsp21 protein and when plants are heat-stressed. The amount of Hsp21 associated with the thylakoid membranes was precisely determined by quantitative mass spectrometry after metabolic 15N-isotope labeling of either recombinantly expressed and purified Hsp21 protein or intact Arabidopsis thaliana plants. We found that Hsp21 is among few proteins that become associated with the thylakoid membranes in heat-stressed plants, and that approximately two thirds of the pool of chloroplast Hsp21 is affected. We conclude that for a complete picture of the role of sHsps in plant stress resistance also their association with the membranes should be considered.
(Less)
- author
- Bernfur, Katja
LU
; Rutsdottir, Gudrun
LU
and Emanuelsson, Cecilia
LU
- organization
- publishing date
- 2017-09
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Chaperone, Heat shock protein, Membranes, Photosynthesis, Quantitative mass spectrometry, Stable isotope labeling, Stress response, Thermomemory
- in
- Protein Science
- volume
- 26
- issue
- 9
- pages
- 1773 - 1784
- publisher
- The Protein Society
- external identifiers
-
- scopus:85021371930
- pmid:28608391
- wos:000409861900009
- ISSN
- 0961-8368
- DOI
- 10.1002/pro.3213
- language
- English
- LU publication?
- yes
- id
- c39ed0c6-71b3-44bd-ae7d-1c63648fa85e
- date added to LUP
- 2017-07-12 14:41:50
- date last changed
- 2024-01-14 00:39:09
@article{c39ed0c6-71b3-44bd-ae7d-1c63648fa85e,
abstract = {{<p>The small heat shock protein (sHsp) chaperones are crucial for cell survival and can prevent aggregation of client proteins that partially unfold under destabilizing conditions. Most investigations on the chaperone activity of sHsps are based on a limited set of thermosensitive model substrate client proteins since the endogenous targets are often not known. There is a high diversity among sHsps with a single conserved β-sandwich fold domain defining the family, the α-crystallin domain, whereas the N-terminal and C-terminal regions are highly variable in length and sequence among various sHsps and conserved only within orthologues. The endogenous targets are probably also varying among various sHsps, cellular compartments, cell type and organism. Here we have investigated Hsp21, a non-metazoan sHsp expressed in the chloroplasts in green plants which experience huge environmental fluctuations not least in temperature. We describe how Hsp21 can also interact with the chloroplast thylakoid membranes, both when isolated thylakoid membranes are incubated with Hsp21 protein and when plants are heat-stressed. The amount of Hsp21 associated with the thylakoid membranes was precisely determined by quantitative mass spectrometry after metabolic <sup>15</sup>N-isotope labeling of either recombinantly expressed and purified Hsp21 protein or intact Arabidopsis thaliana plants. We found that Hsp21 is among few proteins that become associated with the thylakoid membranes in heat-stressed plants, and that approximately two thirds of the pool of chloroplast Hsp21 is affected. We conclude that for a complete picture of the role of sHsps in plant stress resistance also their association with the membranes should be considered.</p>}},
author = {{Bernfur, Katja and Rutsdottir, Gudrun and Emanuelsson, Cecilia}},
issn = {{0961-8368}},
keywords = {{Chaperone; Heat shock protein; Membranes; Photosynthesis; Quantitative mass spectrometry; Stable isotope labeling; Stress response; Thermomemory}},
language = {{eng}},
number = {{9}},
pages = {{1773--1784}},
publisher = {{The Protein Society}},
series = {{Protein Science}},
title = {{The chloroplast-localized small heat shock protein Hsp21 associates with the thylakoid membranes in heat-stressed plants}},
url = {{http://dx.doi.org/10.1002/pro.3213}},
doi = {{10.1002/pro.3213}},
volume = {{26}},
year = {{2017}},
}