Rice Dwarf Virus P2 Protein Hijacks Auxin Signaling by Directly Targeting the Rice OsIAA10 Protein, Enhancing Viral Infection and Disease Development.
The phytohormone auxin plays critical roles in regulating myriads of plant growth and developmental processes. Microbe infection can disturb auxin signaling resulting in defects in these processes, but the underlying mechanisms are poorly understood. Auxin signaling begins with perception of auxin by a transient co-receptor complex consisting of an F-box transport inhibitor response 1/auxin signaling F-box (TIR1/AFB) protein and an auxin/indole-3-acetic acid (Aux/IAA) protein. Auxin binding to the co-receptor triggers ubiquitination and 26S proteasome degradation of the Aux/IAA proteins, leading to subsequent events, including expression of auxin-responsive genes. Here we report that Rice dwarf virus (RDV), a devastating pathogen of rice, causes disease symptoms including dwarfing, increased tiller number and short crown roots in infected rice as a result of reduced sensitivity to auxin signaling. The RDV capsid protein P2 binds OsIAA10, blocking the interaction between OsIAA10 and OsTIR1 and inhibiting 26S proteasome-mediated OsIAA10 degradation. Transgenic rice plants overexpressing wild-type or a dominant-negative (degradation-resistant) mutant of OsIAA10 phenocopy RDV symptoms are more susceptible to RDV infection; however, knockdown of OsIAA10 enhances the resistance of rice to RDV infection. Our findings reveal a previously unknown mechanism of viral protein reprogramming of a key step in auxin signaling initiation that enhances viral infection and pathogenesis.
The State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, People's Republic of China.
Lian
L
Jin
The State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, People's Republic of China.
Qingqing
Q
Qin
The State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, People's Republic of China.
Yu
Y
Wang
The State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, People's Republic of China.
Yingying
Y
Pu
The State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, People's Republic of China.
Lifang
L
Liu
The State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, People's Republic of China.
Xing
X
Wen
The State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, People's Republic of China.
Shaoyi
S
Ji
The State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, People's Republic of China.
Jianguo
J
Wu
The State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, People's Republic of China.
Chunhong
C
Wei
Department of Molecular Genetics and Center for RNA Biology, The Ohio State University, Columbus, Ohio, United States of America.
Biao
B
Ding
The State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, People's Republic of China.
Yi
Y
Li
D036022:Capsid Proteins / Q000235:genetics / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000378:metabolism*; D012275:Oryza / Q000235:genetics / Q000378:metabolism* / Q000821:virology; D010935:Plant Diseases / Q000235:genetics / Q000821:virology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D010942:Plant Viruses / Q000235:genetics / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex / Q000235:genetics / Q000378:metabolism; D059748:Proteolysis; D012087:Reoviridae / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction
D036022:Capsid Proteins; D007210:Indoleacetic Acids; D010940:Plant Proteins; D046988:Proteasome Endopeptidase Complex; C061553:ATP dependent 26S protease