Aphid effectors suppress plant immunity via recruiting defence proteins to processing bodies

Aphids are small insects that have developed specialized mouthparts and unique proteins to establish long-term relationships with plants. The peach-potato aphid, Myzus persicae, is highly adaptable, feeding on a wide variety of plants and capable of transmitting numerous harmful viruses. This study uncovers how host-regulated cathepsins B (CathB) in M. persicae oral secretions help aphids thrive by modulating plant immune responses. Aphid CathB localize to processing bodies (p-bodies) and recruit immune regulators EDS1, PAD4, and ADR1 to these p-bodies, leading to suppression of plant defenses. A plant protein, Acd28.9 (Hsp20 family), counteracts this CathB activity and contributes to plant resistance to aphids. These findings highlight a novel role for p-bodies in plant immunity and uncover a plant resistance mechanism to aphid infestation.