Root transcriptome comparison between grapevines Cabernet Sauvignon, 140 Ruggeri and K51-40 (+/- salt stress)

ABSTRACT: Salt tolerance in grapevine is associated with the exclusion of chloride ions (ClM-bM-^@M-^S) from the shoot. The rate-limiting step for this process has been identified as the passage of ClM-bM-^@M-^S between the root symplast and the xylem apoplast through membrane integral proteins. To identify candidate genes for these proteins we used a custom microarray to compare the root transcriptomes of three grapevine varieties (Vitis spp.) that differ in their capacity to exclude ClM-bM-^@M-^S from shoots. When challenged with 50 mM ClM-bM-^@M-^S there were transcriptional responses that differed across the rootstocks 140 Ruggeri (a good ClM-bM-^@M-^S excluder) and K51-40 (a poor ClM-bM-^@M-^S excluder), and Cabernet Sauvignon (an intermediate ClM-bM-^@M-^S excluder and Vitis vinifera control). The magnitude of these salt-induced changes correlated with the amount of ClM-bM-^@M-^S accumulated in shoots. Abiotic-stress responsive transcripts (e.g. heat shock proteins) were induced in 140 Ruggeri. Respiratory transcripts were repressed in Cabernet Sauvignon. Expression of hypersensitive response and ROS scavenging transcripts were altered in the sensitive K51-40. Despite these differences, no obvious candidate ClM-bM-^@M-^S transporters were identified from the salt treatment. In contrast, under control conditions where differences in shoot ClM-bM-^@M-^S exclusion between rootstocks were still significant, we identified a number of genes encoding putative ion channels including VvSLAH3, VvALMT1, and possible regulators of these proteins such as VvSnRK2.6 and calcium dependent protein kinases (CDPK) as being differentially expressed between rootstocks. Members of the low affinity nitrate transporter (NRT1), and chloride channel (CLC) families were also identified. We propose these as useful candidates for further study within breeding programs aimed at improving plant salt tolerance in grapevine and other crops. Comparative: genotype versus genotype (control); and control (0 mM Cl) versus salt (50 mM Cl). Rooted leaves were grown as described by Gong et. al. (2010) (Journal of Experimental Botany). After 2 weeks of hydroponic growth, plants were exposed to 0 mM or 50 mM chloride stress for 4 days. Three biological replicates were used for 140 Ruggeri. Four biological replicates were used for Cabernet Sauvignon. Four biological replicates were used for K51-40. Each biological replicate consisted of total roots from four individual plants pooled together.

ORGANISM(S): Vitis x champinii x Vitis riparia

SUBMITTER: Sam Henderson 

PROVIDER: E-GEOD-57770 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress