Limits...
Transcriptome profiling of the rice blast fungus during invasive plant infection and in vitro stresses.

Mathioni SM, Beló A, Rizzo CJ, Dean RA, Donofrio NM - BMC Genomics (2011)

Bottom Line: We identified 4,973 genes that were differentially expressed in at least one of the in planta and in vitro stress conditions when compared to fungal mycelia grown in complete medium, which was used as reference.Functional categorization of the 55 induced genes revealed that most were either related to carbon metabolism, membrane proteins, or were involved in oxidoreduction reactions.The 129 repressed genes showed putative roles in vesicle trafficking, signal transduction, nitrogen metabolism, or molecular transport.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Plant and Soil Sciences, University of Delaware, Newark, DE, USA.

ABSTRACT

Background: Rice blast is the most threatening disease to cultivated rice. Magnaporthe oryzae, its causal agent, is likely to encounter environmental challenges during invasive growth in its host plants that require shifts in gene expression to establish a compatible interaction. Here, we tested the hypothesis that gene expression patterns during in planta invasive growth are similar to in vitro stress conditions, such as nutrient limitation, temperature up shift and oxidative stress, and determined which condition most closely mimicked that of in planta invasive growth. Gene expression data were collected from these in vitro experiments and compared to fungal gene expression during the invasive growth phase at 72 hours post-inoculation in compatible interactions on two grass hosts, rice and barley.

Results: We identified 4,973 genes that were differentially expressed in at least one of the in planta and in vitro stress conditions when compared to fungal mycelia grown in complete medium, which was used as reference. From those genes, 1,909 showed similar expression patterns between at least one of the in vitro stresses and rice and/or barley. Hierarchical clustering of these 1,909 genes showed three major clusters in which in planta conditions closely grouped with the nutrient starvation conditions. Out of these 1,909 genes, 55 genes and 129 genes were induced and repressed in all treatments, respectively. Functional categorization of the 55 induced genes revealed that most were either related to carbon metabolism, membrane proteins, or were involved in oxidoreduction reactions. The 129 repressed genes showed putative roles in vesicle trafficking, signal transduction, nitrogen metabolism, or molecular transport.

Conclusions: These findings suggest that M. oryzae is likely primarily coping with nutrient-limited environments at the invasive growth stage 72 hours post-inoculation, and not with oxidative or temperature stresses.

Show MeSH

Related in: MedlinePlus

Venn diagrams of M. oryzae genes differentially expressed in each of the in vitro treatments compared to M. oryzae inoculated in rice and barley leaves. (A) Number of commonly induced (upper panel) or repressed (lower panel) fungal genes during barley and rice infection, with each individual in vitro condition. Temperature up shift (TS); paraquat (PQ); minimal medium (MM); carbon-limited minimal medium (MM-C); nitrogen-limited minimal medium (MM-N). (B) Number of commonly induced (left panel) and repressed (right panel) fungal genes in the nutrient-limited conditions.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3037901&req=5

Figure 3: Venn diagrams of M. oryzae genes differentially expressed in each of the in vitro treatments compared to M. oryzae inoculated in rice and barley leaves. (A) Number of commonly induced (upper panel) or repressed (lower panel) fungal genes during barley and rice infection, with each individual in vitro condition. Temperature up shift (TS); paraquat (PQ); minimal medium (MM); carbon-limited minimal medium (MM-C); nitrogen-limited minimal medium (MM-N). (B) Number of commonly induced (left panel) and repressed (right panel) fungal genes in the nutrient-limited conditions.

Mentions: In order to examine overlapping gene expression profiles between in planta expression and individual in vitro stresses, we generated area-proportional Venn diagrams of induced and repressed genes for rice, barley and each of the in vitro treatments (Figure 3A), along with diagrams showing overlap among the nutrient-limited conditions (Figure 3B).


Transcriptome profiling of the rice blast fungus during invasive plant infection and in vitro stresses.

Mathioni SM, Beló A, Rizzo CJ, Dean RA, Donofrio NM - BMC Genomics (2011)

Venn diagrams of M. oryzae genes differentially expressed in each of the in vitro treatments compared to M. oryzae inoculated in rice and barley leaves. (A) Number of commonly induced (upper panel) or repressed (lower panel) fungal genes during barley and rice infection, with each individual in vitro condition. Temperature up shift (TS); paraquat (PQ); minimal medium (MM); carbon-limited minimal medium (MM-C); nitrogen-limited minimal medium (MM-N). (B) Number of commonly induced (left panel) and repressed (right panel) fungal genes in the nutrient-limited conditions.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3037901&req=5

Figure 3: Venn diagrams of M. oryzae genes differentially expressed in each of the in vitro treatments compared to M. oryzae inoculated in rice and barley leaves. (A) Number of commonly induced (upper panel) or repressed (lower panel) fungal genes during barley and rice infection, with each individual in vitro condition. Temperature up shift (TS); paraquat (PQ); minimal medium (MM); carbon-limited minimal medium (MM-C); nitrogen-limited minimal medium (MM-N). (B) Number of commonly induced (left panel) and repressed (right panel) fungal genes in the nutrient-limited conditions.
Mentions: In order to examine overlapping gene expression profiles between in planta expression and individual in vitro stresses, we generated area-proportional Venn diagrams of induced and repressed genes for rice, barley and each of the in vitro treatments (Figure 3A), along with diagrams showing overlap among the nutrient-limited conditions (Figure 3B).

Bottom Line: We identified 4,973 genes that were differentially expressed in at least one of the in planta and in vitro stress conditions when compared to fungal mycelia grown in complete medium, which was used as reference.Functional categorization of the 55 induced genes revealed that most were either related to carbon metabolism, membrane proteins, or were involved in oxidoreduction reactions.The 129 repressed genes showed putative roles in vesicle trafficking, signal transduction, nitrogen metabolism, or molecular transport.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Plant and Soil Sciences, University of Delaware, Newark, DE, USA.

ABSTRACT

Background: Rice blast is the most threatening disease to cultivated rice. Magnaporthe oryzae, its causal agent, is likely to encounter environmental challenges during invasive growth in its host plants that require shifts in gene expression to establish a compatible interaction. Here, we tested the hypothesis that gene expression patterns during in planta invasive growth are similar to in vitro stress conditions, such as nutrient limitation, temperature up shift and oxidative stress, and determined which condition most closely mimicked that of in planta invasive growth. Gene expression data were collected from these in vitro experiments and compared to fungal gene expression during the invasive growth phase at 72 hours post-inoculation in compatible interactions on two grass hosts, rice and barley.

Results: We identified 4,973 genes that were differentially expressed in at least one of the in planta and in vitro stress conditions when compared to fungal mycelia grown in complete medium, which was used as reference. From those genes, 1,909 showed similar expression patterns between at least one of the in vitro stresses and rice and/or barley. Hierarchical clustering of these 1,909 genes showed three major clusters in which in planta conditions closely grouped with the nutrient starvation conditions. Out of these 1,909 genes, 55 genes and 129 genes were induced and repressed in all treatments, respectively. Functional categorization of the 55 induced genes revealed that most were either related to carbon metabolism, membrane proteins, or were involved in oxidoreduction reactions. The 129 repressed genes showed putative roles in vesicle trafficking, signal transduction, nitrogen metabolism, or molecular transport.

Conclusions: These findings suggest that M. oryzae is likely primarily coping with nutrient-limited environments at the invasive growth stage 72 hours post-inoculation, and not with oxidative or temperature stresses.

Show MeSH
Related in: MedlinePlus