Rice Dwarf Virus P2 Protein Hijacks Auxin Signaling by Directly Targeting the Rice OsIAA10 Protein, Enhancing Viral Infection and Disease Development

• DOI: 10.1371/journal.ppat.1005847
• Publication Date: 2016-09-08T17:33:37Z
• Authors: Lian Jin; Qingqing Qin; Yu Wang; Yingying Pu; Lifang Liu; Xing Wen; Shaoyi Ji; Jianguo Wu; Chunhong Wei; Biao Ding; Yi Li
• Keywords: F-box protein

The phytohormone auxin plays critical roles in regulating myriads of plant growth and developmental processes. Microbe infection can disturb signaling resulting defects these processes, but the underlying mechanisms are poorly understood. Auxin begins with perception by a transient co-receptor complex consisting an F-box transport inhibitor response 1/auxin (TIR1/AFB) protein auxin/indole-3-acetic acid (Aux/IAA) protein. binding to triggers ubiquitination 26S proteasome degradation Aux/IAA proteins, leading subsequent events, including expression auxin-responsive genes. Here we report that Rice dwarf virus (RDV), devastating pathogen rice, causes disease symptoms dwarfing, increased tiller number short crown roots infected rice as result reduced sensitivity signaling. RDV capsid P2 binds OsIAA10, blocking interaction between OsIAA10 OsTIR1 inhibiting proteasome-mediated degradation. Transgenic plants overexpressing wild-type or dominant-negative (degradation-resistant) mutant phenocopy more susceptible infection; however, knockdown enhances resistance infection. Our findings reveal previously unknown mechanism viral reprogramming key step initiation pathogenesis.