Extensive rearrangement of the Arabidopsis mitochondrial genome elicits cellular conditions for thermotolerance.
Three nuclear genes involved in plant mitochondrial recombination surveillance have been previously identified. Simultaneous disruption of two of these genes, MutS Homolog1 (MSH1) and RECA3, results in extensive rearrangement of the mitochondrial genome and dramatic changes in plant growth. We have capitalized on these changes in mitochondrial genome organization to understand the role mitochondria play in plant cellular and developmental processes. Transcript profiling of the double mutants grown under normal conditions revealed differential regulation of numerous nuclear genes involved in stress responses together with increased levels of polyadenylated mitochondrial transcripts. We show that extensive rearrangement of the mitochondrial genome in Arabidopsis (Arabidopsis thaliana) directly elicits physiological stress responses in plants, with msh1 recA3 double mutants exhibiting enhanced thermotolerance. Likewise, we show that mitochondrial transcriptional changes are associated with genome recombination, so that differential gene modulation is accomplished, at least in part, through altered gene copy number.
Center for Plant Science Innovation, University of Nebraska, Lincoln, Nebraska 68588-0660, USA.
Vikas
V
Shedge
Jaime
J
Davila
Maria P
MP
Arrieta-Montiel
Saleem
S
Mohammed
Sally A
SA
Mackenzie
D000222:Adaptation, Physiological / Q000235:genetics*; D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology; D001483:Base Sequence; D017931:DNA Primers; D004272:DNA, Mitochondrial / Q000235:genetics; D020869:Gene Expression Profiling; D018745:Genome, Plant; D009154:Mutation; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics; D013696:Temperature
D017931:DNA Primers; D004272:DNA, Mitochondrial; D012333:RNA, Messenger