Red-light is an environmental effector for mutualism between begomovirus and its vector whitefly

Area of Science:

• Plant-pathogen interactions
• Molecular plant-microbe interactions
• Insect-borne disease ecology

Background:

• Environmental factors like light influence insect vector behavior and disease spread.
• The role of light in host defense modulation and pathogen adaptation for transmission is poorly understood.
• Begomoviruses establish mutualism with whitefly vectors, partly through the viral protein βC1 inhibiting plant jasmonate signaling.

Purpose of the Study:

• To investigate how light conditions affect plant defense mechanisms against insect vectors.
• To elucidate the role of red light in the whitefly-begomovirus mutualistic relationship.
• To understand how begomoviruses co-adapt to light cues to facilitate vector transmission.

Main Methods:

• Investigated the interaction between the begomovirus βC1 protein and PHYTOCHROME-INTERACTING FACTORS (PIFs).
• Analyzed the role of PIFs in regulating plant defense genes, specifically terpene synthase genes.
• Examined the interplay between light signaling (via PIFs) and jasmonate signaling (via MYC2) in plant defense.

Main Results:

• Red light stabilizes the viral βC1 protein, promoting whitefly-begomovirus mutualism.
• PIFs regulate plant defenses against whiteflies by activating terpene synthase gene transcription.
• Begomovirus βC1 disrupts PIF-MYC2 complex formation, inhibiting plant defense gene expression and facilitating virus transmission.

Conclusions:

• Begomoviruses exploit red light signaling by stabilizing the βC1 protein, which interferes with host defense pathways.
• The viral protein βC1 hijacks the integration of light and jasmonate signaling mediated by PIFs and MYC2.
• This viral manipulation enhances the mutualistic relationship between the virus and its whitefly vector, promoting disease spread.