Linked Life Data

19343531

Source:http://linkedlifedata.com/resource/pubmed/id/19343531

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-4-28
pubmed:abstractText
Moderate heat stress has been reported to increase PSI cyclic electron flow (CEF). We subjected leaves of Arabidopsis (Arabidopsis thaliana) mutants disrupted in the regulation of one or the other pathway of CEF flow-crr2 (chlororespiratory reduction, deficient in regulation of chloroplast NAD(P)H dehydrogenase-dependent CEF) and pgr5 (proton gradient regulation, proposed to have reduced efficiency of antimycin-A-sensitive-CEF regulation) to moderate heat stress. Light-adapted leaves were switched from 23 to 40 degrees C in 2 min. Gas exchange, chlorophyll fluorescence, the electrochromic shift (ECS), and P700 were measured. Photosynthesis of crr2 and pgr5 was more sensitive to heat and had less ability to recover than the genetic background gl. The proton conductance in light was increased by heat and it was twice as much in pgr5, which had much smaller light-induced proton motive force. We confirmed that P700 becomes more reduced at high temperature and show that, in contrast, the proportion of PSII open centers (with Q (A) oxidized) increases. The two mutants had much slower P700(+) reduction rate during and after heat than gl. The proportion of light absorbed by PSI versus PSII was increased in gl and crr2 during and after heat treatment, but not in pgr5. We propose that heat alters the redox balance away from PSII and toward PSI and that the regulation of CEF helps photosynthesis tolerate heat stress.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
1573-5079
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
100
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
29-43
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Photosynthetic electron transport and proton flux under moderate heat stress.
pubmed:affiliation
Department of Botany, University of Wisconsin-Madison, 430 Lincoln Drive, Madison, WI 53706, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.