Limits...
Systemic responses in a tolerant olive (Olea europaea L.) cultivar upon root colonization by the vascular pathogen Verticillium dahliae.

Gómez-Lama Cabanás C, Schilirò E, Valverde-Corredor A, Mercado-Blanco J - Front Microbiol (2015)

Bottom Line: A total of 585 FU and 381 FD unigenes were identified, many of them involved in defense response to (a)biotic stresses.Selected genes were then used to validate libraries and evaluate their temporal expression pattern in "Frantoio." Four defense genes were analyzed in cultivars Changlot Real (tolerant) and Picual (susceptible).An association between GRAS1 and DRR2 gene expression patterns and susceptibility to VWO was observed, suggesting that these transcripts could be further evaluated as markers of the tolerance level of olive cultivars to V. dahliae.

View Article: PubMed Central - PubMed

Affiliation: Department of Crop Protection, Institute for Sustainable Agriculture, Consejo Superior de Investigaciones Científicas Córdoba, Spain.

ABSTRACT
Verticillium wilt of olive (VWO) is caused by the vascular pathogen Verticillium dahliae. One of the best VWO management measures is the use of tolerant cultivars; however, our knowledge on VWO tolerance/resistance genetics is very limited. A transcriptomic analysis was conducted to (i) identify systemic defense responses induced/repressed in aerial tissues of the tolerant cultivar Frantoio upon root colonization by V. dahliae, and (ii) determine the expression pattern of selected defense genes in olive cultivars showing differential susceptibility to VWO. Two suppression subtractive hybridization cDNA libraries, enriched in up-regulated (FU) and down-regulated (FD) genes respectively, were generated from "Frantoio" aerial tissues. Results showed that broad systemic transcriptomic changes are taking place during V. dahliae-"Frantoio" interaction. A total of 585 FU and 381 FD unigenes were identified, many of them involved in defense response to (a)biotic stresses. Selected genes were then used to validate libraries and evaluate their temporal expression pattern in "Frantoio." Four defense genes were analyzed in cultivars Changlot Real (tolerant) and Picual (susceptible). An association between GRAS1 and DRR2 gene expression patterns and susceptibility to VWO was observed, suggesting that these transcripts could be further evaluated as markers of the tolerance level of olive cultivars to V. dahliae.

No MeSH data available.


Related in: MedlinePlus

“Level 3” Gene Ontology (GO) “Biological processes” (BP) and “Molecular function” (MF) terms distribution of 381 unigenes repressed (FD) and 585 induced (FU) in olive (Olea europaea L.) aerial tissues colonized by Verticillium dahliae. Unigenes were categorized using the “Blast2GO” software.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4584997&req=5

Figure 1: “Level 3” Gene Ontology (GO) “Biological processes” (BP) and “Molecular function” (MF) terms distribution of 381 unigenes repressed (FD) and 585 induced (FU) in olive (Olea europaea L.) aerial tissues colonized by Verticillium dahliae. Unigenes were categorized using the “Blast2GO” software.

Mentions: Blast2GO analysis of the EST set enabled annotation of expressed sequences according to the terms of the three main GO vocabularies, i.e., “Biological Process” (BP), “Molecular Function” (MF), and “Cellular Component” (CC). GO annotation was only feasible for 57.3% (up-regulated genes) and 68.3% (down-regulated genes) of the sequences, i.e., 141 and 89 ESTs, respectively. A total of 140 FD and 88 FU assigned to “unknown” category and 1 FU and 1 FD assigned to “predicted” category were automatically excluded from the analysis by the program. Since a number of transcripts were identified by different GO terms, the mapped ESTs distribution for BP and MF main categories shown in Figure 1 resulted in more than 585 (FU) or 381 (FD) sequences. The distribution of assignments into GO categories “level 3” was 336 (FU) and 226 (FD) (for BP), 311 (FU) and 202 (FD) (for MF), and 266 (FU) and 201 (FD) (for CC). Regarding to BP main GO vocabulary, transcripts representing GO terms categories non-related to plant defense processes (e.g., anatomical structure development, primary metabolic process, reproductive process, etc.), were grouped as “other” (Figure 1, BP). Concerning to plant defense-related categories, ESTs found to be induced or repressed in above-ground organs upon V. dahliae olive root colonization were assigned to processes such as “response to stress” (80 FU and 66 FD unigenes), “response to abiotic stimuli” (74 FU and 54 FD), “response to biotic stimuli” (28 FU and 32 FD), “response to external stimuli” (33 FU and 35 FD) or “response to endogenous stimuli” (21 FU and 11 FD). GO terms included catalases (CATs), proteins involved in the phenylpropanoid pathway, ET biosynthesis (ACO) or terpenoids biosynthesis, proteins related to SA (ACL), linolenic acid metabolism and PR protein. In addition, we identified several transcription factors (TF) such as WRKY's (WRKY20, WRKY44, WRKY33, WRKY40) or GRAS1, ET-responsive TF rap2-12-like, elongation factors (EF-1α, EF-1β, and EF-1Δ) and proteins directly related with stress responses (for a complete list of unigenes, see Tables S1, S2).


Systemic responses in a tolerant olive (Olea europaea L.) cultivar upon root colonization by the vascular pathogen Verticillium dahliae.

Gómez-Lama Cabanás C, Schilirò E, Valverde-Corredor A, Mercado-Blanco J - Front Microbiol (2015)

“Level 3” Gene Ontology (GO) “Biological processes” (BP) and “Molecular function” (MF) terms distribution of 381 unigenes repressed (FD) and 585 induced (FU) in olive (Olea europaea L.) aerial tissues colonized by Verticillium dahliae. Unigenes were categorized using the “Blast2GO” software.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4584997&req=5

Figure 1: “Level 3” Gene Ontology (GO) “Biological processes” (BP) and “Molecular function” (MF) terms distribution of 381 unigenes repressed (FD) and 585 induced (FU) in olive (Olea europaea L.) aerial tissues colonized by Verticillium dahliae. Unigenes were categorized using the “Blast2GO” software.
Mentions: Blast2GO analysis of the EST set enabled annotation of expressed sequences according to the terms of the three main GO vocabularies, i.e., “Biological Process” (BP), “Molecular Function” (MF), and “Cellular Component” (CC). GO annotation was only feasible for 57.3% (up-regulated genes) and 68.3% (down-regulated genes) of the sequences, i.e., 141 and 89 ESTs, respectively. A total of 140 FD and 88 FU assigned to “unknown” category and 1 FU and 1 FD assigned to “predicted” category were automatically excluded from the analysis by the program. Since a number of transcripts were identified by different GO terms, the mapped ESTs distribution for BP and MF main categories shown in Figure 1 resulted in more than 585 (FU) or 381 (FD) sequences. The distribution of assignments into GO categories “level 3” was 336 (FU) and 226 (FD) (for BP), 311 (FU) and 202 (FD) (for MF), and 266 (FU) and 201 (FD) (for CC). Regarding to BP main GO vocabulary, transcripts representing GO terms categories non-related to plant defense processes (e.g., anatomical structure development, primary metabolic process, reproductive process, etc.), were grouped as “other” (Figure 1, BP). Concerning to plant defense-related categories, ESTs found to be induced or repressed in above-ground organs upon V. dahliae olive root colonization were assigned to processes such as “response to stress” (80 FU and 66 FD unigenes), “response to abiotic stimuli” (74 FU and 54 FD), “response to biotic stimuli” (28 FU and 32 FD), “response to external stimuli” (33 FU and 35 FD) or “response to endogenous stimuli” (21 FU and 11 FD). GO terms included catalases (CATs), proteins involved in the phenylpropanoid pathway, ET biosynthesis (ACO) or terpenoids biosynthesis, proteins related to SA (ACL), linolenic acid metabolism and PR protein. In addition, we identified several transcription factors (TF) such as WRKY's (WRKY20, WRKY44, WRKY33, WRKY40) or GRAS1, ET-responsive TF rap2-12-like, elongation factors (EF-1α, EF-1β, and EF-1Δ) and proteins directly related with stress responses (for a complete list of unigenes, see Tables S1, S2).

Bottom Line: A total of 585 FU and 381 FD unigenes were identified, many of them involved in defense response to (a)biotic stresses.Selected genes were then used to validate libraries and evaluate their temporal expression pattern in "Frantoio." Four defense genes were analyzed in cultivars Changlot Real (tolerant) and Picual (susceptible).An association between GRAS1 and DRR2 gene expression patterns and susceptibility to VWO was observed, suggesting that these transcripts could be further evaluated as markers of the tolerance level of olive cultivars to V. dahliae.

View Article: PubMed Central - PubMed

Affiliation: Department of Crop Protection, Institute for Sustainable Agriculture, Consejo Superior de Investigaciones Científicas Córdoba, Spain.

ABSTRACT
Verticillium wilt of olive (VWO) is caused by the vascular pathogen Verticillium dahliae. One of the best VWO management measures is the use of tolerant cultivars; however, our knowledge on VWO tolerance/resistance genetics is very limited. A transcriptomic analysis was conducted to (i) identify systemic defense responses induced/repressed in aerial tissues of the tolerant cultivar Frantoio upon root colonization by V. dahliae, and (ii) determine the expression pattern of selected defense genes in olive cultivars showing differential susceptibility to VWO. Two suppression subtractive hybridization cDNA libraries, enriched in up-regulated (FU) and down-regulated (FD) genes respectively, were generated from "Frantoio" aerial tissues. Results showed that broad systemic transcriptomic changes are taking place during V. dahliae-"Frantoio" interaction. A total of 585 FU and 381 FD unigenes were identified, many of them involved in defense response to (a)biotic stresses. Selected genes were then used to validate libraries and evaluate their temporal expression pattern in "Frantoio." Four defense genes were analyzed in cultivars Changlot Real (tolerant) and Picual (susceptible). An association between GRAS1 and DRR2 gene expression patterns and susceptibility to VWO was observed, suggesting that these transcripts could be further evaluated as markers of the tolerance level of olive cultivars to V. dahliae.

No MeSH data available.


Related in: MedlinePlus