The proxiome of a plant viral protein with dual targeting to mitochondria and chloroplasts revealed MAPK cascade and splicing components as proviral factors

• DOI: 10.1111/tpj.70161
• Publication Date: 2025-04-14T15:50:17Z
• Authors: María Sáiz‐Bonilla; Yuanyuan Li; Christian Montes‐...; Justin W. Walley; Savithramma P. Di...; Vicente Pallás; Jose A. Navarro
• Keywords: Bimolecular fluorescence complementation; Splicing factor; RNA Silencing

SUMMARY The coat protein (CP) of the melon necrotic spot virus (MNSV) is a multifunctional factor localized in chloroplast, mitochondria, and cytoplasm, playing critical role overcoming plant defenses such as RNA silencing (RNAi) hypersensitive response. However, molecular mechanisms through which CP interferes with remain unclear. Identifying viral–host interactors can reveal how viruses exploit fundamental cellular processes help elucidate viral survival strategies. Here, we employed TurboID‐based proximity labeling approach to identify both wild‐type MNSV cytoplasmic mutant lacking dual transit peptide (ΔNtCP). Of interactors, eight were selected for silencing. Notably, MAP4K SIK1 NbMAP3Kε1 kinases, splicing homolog NbSMU2 significantly reduced accumulation, suggesting proviral these proteins plants. Yeast two‐hybrid bimolecular fluorescence complementation assays confirmed ΔNtCP interaction but not NbSIK1, interacted NbMAP3Kε1. These findings open up new possibilities exploring might modulate gene expression MAPK, thereby facilitating infection.