Robust Cytonuclear Coordination of Transcription in Nascent Arabidopsis thaliana Autopolyploids.
Polyploidy is hypothesized to cause dosage imbalances between the nucleus and the other genome-containing organelles (mitochondria and plastids), but the evidence for this is limited. We performed RNA-seq on Arabidopsis thaliana diploids and their derived autopolyploids to quantify the degree of inter-genome coordination of transcriptional responses to nuclear whole genome duplication in two different organs (sepals and rosette leaves). We show that nuclear and organellar genomes exhibit highly coordinated responses in both organs. First, organelle genome copy number increased in response to nuclear whole genome duplication (WGD), at least partially compensating for altered nuclear genome dosage. Second, transcriptional output of the different cellular compartments is tuned to maintain diploid-like levels of relative expression among interacting genes. In particular, plastid genes and nuclear genes whose products are plastid-targeted show coordinated down-regulation, such that their expression levels relative to each other remain constant across ploidy levels. Conversely, mitochondrial genes and nuclear genes with mitochondrial targeting show either constant or coordinated up-regulation of expression relative to other nuclear genes. Thus, cytonuclear coordination is robust to changes in nuclear ploidy level, with diploid-like balance in transcript abundances achieved within three generations after nuclear whole genome duplication.
['Coate|Jeremy E|JE|', 'Schreyer|W Max|WM|', 'Kum|David|D|', 'Doyle|Jeff J|JJ|']
D017360:Arabidopsis D002467:Cell Nucleus D004171:Diploidy D019143:Evolution, Molecular D018506:Gene Expression Regulation, Plant D017343:Genes, Plant D018745:Genome, Plant D008928:Mitochondria D015388:Organelles D018087:Plastids D011123:Polyploidy D017423:Sequence Analysis, RNA D015533:Transcriptional Activation
transcription Arabidopsis thaliana polyploidy cytonuclear interactions