Linked Life Data

17043890

Source:http://linkedlifedata.com/resource/pubmed/id/17043890

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2007-6-4
pubmed:abstractText
Compared with our knowledge of senescence in annuals and biennials, little is known about age-related changes in perennials. To get new insights into the mechanisms underlying aging in perennials, we measured oxidative stress markers in leaves and organelles, together with abscisic acid levels in leaves of 2- and 7-year-old Cistus clusii dunal plants grown under Mediterranean field conditions. Recently emerged leaves, which either appeared during autumn or spring, were compared to evaluate the effects of environmental constraints on oxidative stress and abscisic acid accumulation as plants aged. Plant aging led to an enhanced oxidation of ot-tocopherol and ascorbate, increased lipid peroxidation and reduced PSII efficiency in leaves during the more stressful conditions of spring and summer, but not during autumn. Analyses of lipid peroxidation in organelles isolated from the same leaves revealed that oxidative stress occurred both in chloroplasts and mitochondria. Although both plant groups showed similar leaf water and nitrogen contents throughout the study, abscisic acid levels were markedly higher (up to 75%) in 7-year-old plants compared to 2-year-old plants throughout the study. It is concluded that (a) meristematic tissues of C. clusii maintain the capacity to make new leaves with no symptoms of oxidative stress for several years, unless these leaves are exposed to environmental constraints, (b) leaves of oldest plants show higher oxidative stress than those of young plants when exposed to adverse climatic conditions, thus supporting the idea that the oxidative stress associated with aging is due at least partly to extrinsic factors, (c) at the subcellular level, age-induced oxidative stress occurs both in chloroplasts and mitochondria, and (d) even in the absence of environmental stress, newly emerged leaves accumulate higher amounts of ABA as plants age.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0032-0935
pubmed:author
pubmed:issnType
Print
pubmed:volume
225
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1039-49
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Age-related changes in oxidative stress markers and abscisic acid levels in a drought-tolerant shrub, Cistus clusii grown under Mediterranean field conditions.
pubmed:affiliation
Departament de Biologia Vegetal, Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 645, 08028 Barcelona, Spain. smunne@ub.edu
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't