June
2007
, Volume
20
, Number
6
Pages
671
-
681
Authors
Masanori
Kaido
,
1
Yosuke
Inoue
,
1
Yoshika
Takeda
,
1
Kazuhiko
Sugiyama
,
1
Atsushi
Takeda
,
1
Masashi
Mori
,
2
Atsushi
Tamai
,
3
Tetsuo
Meshi
,
3
Tetsuro
Okuno
,
1
and
Kazuyuki
Mise
1
Affiliations
1Laboratory of Plant Pathology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan; 2Laboratory of Plant Molecular Genetics, Research Institute of Agricultural Resources, Ishikawa Agricultural College, 1-308, Suematsu, Nonoichi-machi, Ishikawa 951-8836, Japan; 3National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan
Go to article:
RelatedArticle
Accepted 3 January 2007.
Abstract
The 3a movement protein (MP) plays a central role in the movement of the RNA plant virus, Brome mosaic virus (BMV). To identify host factor genes involved in viral movement, a cDNA library of Nicotiana benthamiana, a systemic host for BMV, was screened with far-Western blotting using a recombinant BMV MP as probe. One positive clone encoded a protein with sequence similarity to the α chain of nascent-polypeptide-associated complex from various organisms, which is proposed to contribute to the fidelity of translocation of newly synthesized proteins. The orthologous gene from N. benthamiana was designated NbNACa1. The binding of NbNACa1 to BMV MP was confirmed in vivo with an agroinfiltration-immunoprecipitation assay. To investigate the involvement of NbNACa1 in BMV multiplication, NbNACa1-silenced (GSNAC) transgenic N. benthamiana plants were produced. Downregulation of NbNACa1 expression reduced virus accumulation in inoculated leaves but not in protoplasts. A microprojectile bombardment assay to monitor BMV-MP-assisted viral movement demonstrated reduced virus spread in GSNAC plants. The localization to the cell wall of BMV MP fused to green fluorescent protein was delayed in GSNAC plants. From these results, we propose that NbNACa1 is involved in BMV cell-to-cell movement through the regulation of BMV MP localization to the plasmodesmata.
JnArticleKeywords
Additional keywords:
α-NAC.
Page Content
ArticleCopyright
© 2007 The American Phytopathological Society