ITS MODIFIED ONE COMPARE TO LAST ONE.

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2. Name: Koli Ganapati
ID.No.: MA1TAE0134
Sr. Msc (Agri)
ROLE OF PATHOGEN DERIVEDROLE OF PATHOGEN DERIVED
EFFECTOR PROTEINS IN PLANTEFFECTOR PROTEINS IN PLANT
DISEASE AND RESISTANCEDISEASE AND RESISTANCE
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3. 1) Introduction
2) Mechanism of Effectors
3) Evolutionary process
4) Case studies
5) Conclusion
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Effectors - Pathogen proteins, small molecules that
alter host-cell structure and function.
Dual role of effector protein
1)Disease development
2) Defense system
(Hogenhout et al., 2008)
INTRODUCTION

5. Effectors
 Effector- host Immunity
 Ability to trigger the hypersensitive response in resistant
plants (avirulence activity) then suppress defence
 Virulence in susceptible plants (typically host plants that
lack effective resistance[R] genes)
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(Block et al.,2008)

6. Mechanism of Effectors
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(Hogenhout et al., 2008)
1. Delivery of effectors into host cells
2. Action of effectors in the apoplast
3. Suppression of Plant immunity
4. Some effectors alter plant behavior and
development
5. Molecular mimicry by effectors

7. 1. Delivery of effectors into host cells
Plant deliver effector proteins inside host cells through a
diversity of mechanism
Virus
Bacteria -T3SS (Block et al., 2008)
Fungi – haustoria (Whisson et al., 2007)
Plant parasitic nematodes –the stylet to inject their effector
proteins inside a parasitized plant vascular cell
(Davis et al, 2008)
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8. Fungi
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9. Bacteria -T3SS
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(Block et al., 2008)

10. Virus
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11. Nematodes –Stylet
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12. Resistance and disease pathway
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(Goel et al.,2007)

13. 2. Action of effectors in the apoplast
Act at the plant-microbe interface, where they interfere with
apoplastic plant defenses
(Van der Hoorn, 2008)
Examples
1) Effectors of Cladosporium fulvum.
- Parasite of tomato
- Avr2, Avr9, Avr4, and ECP2 - function exclusively in the
apoplast
(Thomma et al., 2005)
2) Oomycetes - Phytophthora infestans - secrete apoplastic effectors
(Tian et al.,
2007)
Inhibit and protect pathogen against plant hydrolytic enzyme.
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14. 1) Contributes to virulence by suppressing basal defenses
2) Suppress hypersensitive cell death elicited by various Avr
proteins
Examples
 Oomycete - RXLR effectors suppress host immunity
 P. infestans -Avr3a suppresses the hypersensitive cell death
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3. Suppression of Plant immunity

15. 4. Effectors Alter Plant Behavior and Development
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Coronatine

16. 5. Molecular mimicry by effectors
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17. 4) Evolutionary Process
Four-part model for Plant disease and resistance
“ Central Dogma of Plant Pathology”
A) PAMP recognition triggers immunity -Resistance
B) Effectors suppress immunity - Susceptibility
C) R proteins recognize effector activities-Resistance
D) Effector recognized by R protein is lost or modified
-Susceptibility
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( Bent and Mackey 2007)

18. “Central Dogma” of Plant Pathology
(Bent and Mackey, 2007)
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19. Plant resistant gene
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(Hammond-Kosack and Kanyuka, 2007)

20. Functions of effector proteins from Plant pathogenic bacteria
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21. Functions of effector protein from plant pathogenic fungi
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(Ioannis et al., 2009)

22. Contd.,
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(Ioannis et al., 2009)

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24. Objective: Role of for CRN effectors in the suppression of host
defense responses.
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25. (Tingli Liu et al.,2011)
Identification of a group of P. sojae-specific effectors.
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26. Relative expression of PsCRN63, PsCRN77, PsCRN84, PsCRN86, and
PsCRN115 in vegetative hyphae. Expression levels relative to PsCRN63.
Expression analysis of the group of CRN effectors in P. sojae.
(Tingli Liu et al.,2011)
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27. Functional analysis of PsCRN63 and PsCRN115
A PsCRN63 triggers cell death in N. benthamiana. PsojNIP (positive
control), PsCRN63, PsCRN115, or gfp (negative control). Photographs
were taken 5 d after infiltration. (Tingli Liu et al.,2011)
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28. Generation of transformants with silenced PsCRN63 and PsCRN115 genes.
Relative expression of PsCRN63 and PsCRN115 in silenced lines T3, T20, and
T21 and the wild type (WT) is shown.
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29. Objective: To know the role of how plants succesfully elicit
HR based PCD in response to effectors activity.
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(Robert et al, 2005)
AvrPtoB induced disease susceptibility in
RGpto11 tomato leaves

31. Objective:
To find a novel model for the involvement of host
factors in effectors recognition.
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33. Objective :
The role of Mi-CRT in the plant– nematode interaction and
showed that the knock-down of MiCRT gene expression in
nematodes decreased the ability of these parasites to infect plants.
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34. Effect of calreticulin (CRT) Mi-CRT knockdown on Meloidogyne
incognita virulence.
(Jaouannet et al., 2012)
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35. Effect of the overproduction of calreticulin (CRT) Mi-CRT on
Arabidopsis thaliana susceptibility to Meloidogyne incognita.
(Jaouannet et al., 2012)
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