NTH201, a novel class II KNOTTED1-like protein, facilitates the cell-to-cell movement of Tobacco mosaic virus in tobacco.
NTH201, a novel class II KNOTTED1-like protein gene, was cloned from tobacco (Nicotiana tabacum cv. Xanthi) and its role in Tobacco mosaic virus (TMV) infection was analyzed. Virus-induced gene silencing of NTH201 caused a delay in viral RNA accumulation as well as virus spread in infected tobacco plants. Overexpression of the gene in a transgenic tobacco plant (N. tabacum cv. Xanthi nc) infected by TMV showed larger local lesions than those of the nontransgenic plant. NTH201 exhibited no intercellular trafficking ability but did exhibit colocalization with movement protein (MP) at the plasmodesmata. When NTH201-overexpressing tobacco BY-2 cultured cells were infected with TMV, the accumulation of MP but not of viral genomic and subgenomic RNA clearly was accelerated compared with those in nontransgenic cells at an early infection period. The formation of virus replication complexes (VRC) also was accelerated in these transgenic cells. Conversely, NTH201-silenced cells showed less MP accumulations and fewer VRC formations than did nontransgenic cells. These results suggested that NTH201 might indirectly facilitate MP accumulation and VRC formation in TMV-infected cells, leading to rapid viral cell-to-cell movement in plants at an early infection stage.
Yoshii
Atsushi
A
Laboratory of Plant Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan.
Shimizu
Takumi
T
Yoshida
Akiko
A
Hamada
Koji
K
Sakurai
Keitaro
K
Yamaji
Yasuyuki
Y
Suzuki
Masashi
M
Namba
Shigetou
S
Hibi
Tadaaki
T
D000595:Amino Acid Sequence; D002478:Cells, Cultured; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics; D020868:Gene Silencing; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D010935:Plant Diseases / Q000235:genetics* / Q000821:virology; D010940:Plant Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014026:Nicotiana / Q000166:cytology / Q000235:genetics* / Q000821:virology; D014027:Tobacco Mosaic Virus / Q000254:growth & development*
D018744:DNA, Plant; D010940:Plant Proteins