Ligand-induced receptor activation,

Concentration of PI 3-phosphates rises

PH domain of PKB binds to PI 3-phosphates

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#Id: 9781

#Unit 6. System Physiology – Plant

R gene products are also called as NBS–LRR

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#Unit 6. System Physiology – Plant

According to the guard hypothesis, R gene products “guard” cellular proteins, which are called guardees or decoys

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#Unit 6. System Physiology – Plant

Guard hypothesis says that the Interaction between the guardees and the pathogen effectors is required for successful infection by the pathogen.

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#Unit 6. System Physiology – Plant

The NBS–LRR receptor remains inactive when bound to the guardee. However, when the effector interacts with the guardee, the NBS– LRR receptor becomes activated, triggering a signaling cascade that leads to the defense response.

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#Unit 6. System Physiology – Plant

R gene Mi-1 confers resistance to aphids and whiteflies

Rice R gene Bph14 confers resistance to the brown plant hopper

Melon R gene Vat confers resistance to the cotton aphid. 

All of these R genes encode NBS–LRR receptors.

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#Unit 6. System Physiology – Plant

Tomato Cf genes is also encodes a R proteins that recognize apoplastic effectors are receptor‐like proteins (RLPs) against the extracellular colonizing fungus Cladosporium fulvum for Avr9