Figure 6.

Expression profiles of VvWRKY genes in response to abiotic stresses. Expression of VvWRKY genes in the V. vinifera cv ‘Cabernet Sauvignon’ (microarray) or 4-week-old in vitro explants of V. vinifera PN40024 genotype (qRT-PCR) in response to cold (cold), drought (WS) and salt stress (SS). Microarray analysis presented in a and b. qRT-PCR data presented in c. Microarray data were downloaded from the NCBI GEO datasets (GSE31594 and GSE31677), processed as log₂ of the ratio between treated and untreated samples and graphically represented with MeV software. (a) V. vinifera cv ‘Cabernet Sauvignon’ plants grown in a hydroponic drip system were treated with 120 mM salt (SS), polyethylene glycol (PEG), cold (5 °C) or left untreated. Shoots with leaves were collected at 0, 1, 4 and 8 h for all treatments, and at 24 h for all treatments except cold (GEO series GSE31594). (b) Potted V. vinifera cv ‘Cabernet Sauvignon’ vines in the greenhouse were exposed to a water-deficit stress (WC) by withholding water or a salt stress (SS) by watering plants with a saline solution for 16 days. Non-stressed, normally watered plants served as the control for both treatments. Shoot tips were harvested every 4 days (0, 4, 8, 12 and 16 days) (GEO series GSE31677). (c) qRT-PCR expression analysis of VvWRKYs in V. vinifera PN40024 genotype subjected to a drought treatment. Transcripts were normalized to the actin gene expression. The mean±s.d. of three biological replicates are presented. Asterisks indicate that the corresponding gene was significantly up- or downregulated in a given organ (*p≤0.05, **p≤0.01). MeV, Multi Experiment Viewer.