Stress-induced co-expression of alternative respiratory chain components in Arabidopsis thaliana.
Plant mitochondria contain non-phosphorylating bypasses of the respiratory chain, catalysed by the alternative oxidase (AOX) and alternative NADH dehydrogenases (NDH), as well as uncoupling (UCP) protein. Each of these components either circumvents or short-circuits proton translocation pathways, and each is encoded by a small gene family in Arabidopsis. Whole genome microarray experiments were performed with suspension cell cultures to examine the effects of various 3 h treatments designed to induce abiotic stress. The expression of over 60 genes encoding components of the classical, phosphorylating respiratory chain and tricarboxylic acid cycle remained largely constant when cells were subjected to a broad range of abiotic stresses, but expression of the alternative components responded differentially to the various treatments. In detailed time-course quantitative PCR analysis, specific members of both AOX and NDH gene families displayed coordinated responses to treatments. In particular, the co-expression of AOX1a and NDB2 observed under a number of treatments suggested co-regulation that may be directed by common sequence elements arranged hierarchically in the upstream promoter regions of these genes. A series of treatment sets were identified, representing the response of specific AOX and NDH genes to mitochondrial inhibition, plastid inhibition and abiotic stresses. These treatment sets emphasise the multiplicity of pathways affecting alternative electron transport components in plants.
Clifton
Rachel
R
Plant Molecular Biology Group, School of Biomedical and Chemical Sciences, The University of Western Australia, Crawley, Western Australia, Australia.
Lister
Ryan
R
Parker
Karen L
KL
Sappl
Pia G
PG
Elhafez
Dina
D
Millar
A Harvey
AH
Day
David A
DA
Whelan
James
J
D000693:Anaerobiosis; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D018929:Cell Culture Techniques; D016000:Cluster Analysis; D004579:Electron Transport / Q000187:drug effects / Q000235:genetics; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D007473:Ion Channels; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism; D009245:NADH Dehydrogenase / Q000235:genetics / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics; D000071256:Uncoupling Protein 1; D015262:Xenobiotics / Q000494:pharmacology*; D000099188:Alternative Oxidase
D029681:Arabidopsis Proteins; D002352:Carrier Proteins; D007473:Ion Channels; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D009245:NADH Dehydrogenase; D010088:Oxidoreductases; D010940:Plant Proteins; D000071256:Uncoupling Protein 1; D015262:Xenobiotics; D000099188:Alternative Oxidase