Unknown,Transcriptomics,Genomics,Proteomics

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Functional divergence of PP2Cs encoding genes in Brassica oleracea and Arabidopsis thaliana

ABSTRACT: We investigated the expression profiles and genomic organization of PP2Cs-encoding genes in Brassica oleracea. Analysis of cDNA macroarray transcription profiles for Brassica oleracea and Arabidopsis thaliana revealed significant differences in the expression of a gene encoding protein phosphatase 2C, ABI1, a member of the group A PP2C. To gain insight into the ABA signaling network conservation in a model plant and its crop relatives group A PP2C genes in B. oleracea have been identified and functionally characterized. Twenty homologous sequences were identified as putative members of the group A PP2Cs (BolC.PP2Cs). Phylogenetic analysis revealed that the B. oleracea homologues are closely related to the particular members of the A. thaliana PP2C family. The genetic analysis has corroborated the presence of 2 to 3 copies for almost all of the PP2Cs examined, which corresponded to the unique genes in the A. thaliana genome. Gene expression analyses showed that among 15 PP2Cs-encoding genes studied in B.oleracea, BolC.ABI2, BolC.HAB1, BolC.HAB2.a-c, and BolC.PP2CA.a were drought-induced. However, in contrary to AtPP2Cs, only BolC.ABI1.a-b, BolC.ABI2 and BolC.PP2CA.a were ABA-responsive at the time points tested. Our results indicate that in B. oleracea PP2C-based drought stress signaling has evolved distinctly in comparison to A. thaliana. It is hypothesized that different reactions of particular B. oleracea PP2C genes to the water stress and ABA treatment may indicate lower conservation of their specificity in stress-induced reversible phosphorylation-based protein network operating in B. oleracea and A. thaliana. For each genotype 7 samples were analysed; 4 controls and 3 samples extracted from drought-treated plants. The reliability and reproducibility of the macroarray analyses were ensured by using biological replicates in the experiment.

ORGANISM(S): Arabidopsis thaliana

SUBMITTER: Agnieszka LudwikM-CM-3w

PROVIDER: E-GEOD-39753 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Functional divergence of PP2Cs encoding genes in Brassica oleracea and Arabidopsis thaliana

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