Arabidopsis transcript and metabolite profiles: ecotype-specific responses to open-air elevated [CO2].
A Free-Air CO(2) Enrichment (FACE) experiment compared the physiological parameters, transcript and metabolite profiles of Arabidopsis thaliana Columbia-0 (Col-0) and Cape Verde Island (Cvi-0) at ambient (approximately 0.375 mg g(-1)) and elevated (approximately 0.550 mg g(-1)) CO(2) ([CO(2)]). Photoassimilate pool sizes were enhanced in high [CO(2)] in an ecotype-specific manner. Short-term growth at elevated [CO(2)] stimulated carbon gain irrespective of down-regulation of plastid functions and altered expression of genes involved in nitrogen metabolism resembling patterns observed under N-deficiency. The study confirmed well-known characteristics, but the use of a time course, ecotypic genetic differences, metabolite analysis and the focus on clusters of functional categories provided new aspects about responses to elevated [CO(2)]. Longer-term Cvi-0 responded by down-regulating functions favouring carbon accumulation, and both ecotypes showed altered expression of genes for defence, redox control, transport, signalling, transcription and chromatin remodelling. Overall, carbon fixation with a smaller commitment of resources in elevated [CO(2)] appeared beneficial, with the extra C only partially utilized possibly due to disturbance of the C : N ratio. To different degrees, both ecotypes perceived elevated [CO(2)] as a metabolic perturbation that necessitated increased functions consuming or storing photoassimilate, with Cvi-0 emerging as more capable of acclimating. Elevated [CO(2)] in Arabidopsis favoured adjustments in reactive oxygen species (ROS) homeostasis and signalling that defined genotypic markers.
Li
Pinghua
P
Department of Plant Biology, University of Illinois at Urbana - Champaign, Urbana, IL 61801, USA.
Ainsworth
Elizabeth A
EA
Leakey
Andrew D B
AD
Ulanov
Alexander
A
Lozovaya
Vera
V
Ort
Donald R
DR
Bohnert
Hans J
HJ
D000064:Acclimatization; D000388:Air; D000704:Analysis of Variance; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism* / Q000502:physiology; D050260:Carbohydrate Metabolism; D002245:Carbon Dioxide / Q000378:metabolism*; D002874:Chromosome Mapping; D019295:Computational Biology; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D008954:Models, Biological; D005810:Multigene Family; D009584:Nitrogen / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D018749:RNA, Plant / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
D018749:RNA, Plant; D002245:Carbon Dioxide; D009584:Nitrogen