Gene expression responses of paper birch (Betula papyrifera) to elevated CO2 and O3 during leaf maturation and senescence.
Gene expression responses of paper birch (Betula papyrifera) leaves to elevated concentrations of CO(2) and O(3) were studied with microarray analyses from three time points during the summer of 2004 at Aspen FACE. Microarray data were analyzed with clustering techniques, self-organizing maps, K-means clustering and Sammon's mappings, to detect similar gene expression patterns within sampling times and treatments. Most of the alterations in gene expression were caused by O(3), alone or in combination with CO(2). O(3) induced defensive reactions to oxidative stress and earlier leaf senescence, seen as decreased expression of photosynthesis- and carbon fixation-related genes, and increased expression of senescence-associated genes. The effects of elevated CO(2) reflected surplus of carbon that was directed to synthesis of secondary compounds. The combined CO(2)+O(3) treatment resulted in differential gene expression than with individual gas treatments or in changes similar to O(3) treatment, indicating that CO(2) cannot totally alleviate the harmful effects of O(3).
Kontunen-Soppela
Sari
S
Finnish Forest Research Institute, Suonenjoki, Finland. sari.kontunen-soppela@joensuu.fi
Parviainen
Juha
J
Ruhanen
Hanna
H
Brosché
Mikael
M
Keinänen
Markku
M
Thakur
Ramesh C
RC
Kolehmainen
Mikko
M
Kangasjärvi
Jaakko
J
Oksanen
Elina
E
Karnosky
David F
DF
Vapaavuori
Elina
E
D000393:Air Pollutants / Q000633:toxicity*; D029662:Betula / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D002245:Carbon Dioxide / Q000378:metabolism*; D015870:Gene Expression / Q000187:drug effects*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D020411:Oligonucleotide Array Sequence Analysis; D010126:Ozone / Q000633:toxicity*; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development
D000393:Air Pollutants; D002245:Carbon Dioxide; D010126:Ozone