Lab. Plant Pathology Professor: Okuno, T., Associate Professor: Mise, K., Associate Professor: Takano, Y., Instructor: Kaido, M.

Plant Pathology, a Basic Science for Plant Protection

Studies on virus infection and symptom development in plants

We are studying infection mechanisms of plant viruses and plant pathogenic fungi. Our research includes identification and characterization of viral and fungal factors involved in the expression of pathogenesis and their interaction with plant factors. We are analyzing the mechanisms of translation, RNA replication and viral movement in plants, organelle dynamics and signaling cascades for fungal pathogenesis, and plant defense mechanisms against viral and fungal pathogen attack.

Studies on the mechanisms by which viruses suppress the plant’s resistance, circumvent host defense, and multiply in hosts To accomplish infection, viruses exploit host machinery for infection. Despite their small genomic size, RNA viruses have all the elements in their genome that are required to complete infection and to counteract host defenses. The figure (right) shows the ability of a virus to suppress a plant resistance mechanism called RNA silencing.

Expression of the Gerry fish green fluorescence protein (GFP) gene is suppressed in transgenic plants transformed with the GFP gene (right), whereas GFP fluorescence is consistently observed in virus-infected plants (left).

Virus spread in plants can be visualized using GFP-tagged chimeric viruses (left). Some viruses show symptomless infection in a certain plant species and cause severe symptoms in a plant having a specific gene involved in symptom development (right).

Plant viruses utilize host proteins to establish infection including replication, cell-to-cell movement and long-distance movement and eventually induce symptoms in plants. Surveys for virus and plant genes involved in these processes have been progressing by using bromoviruses and Arabidopsis thaliana.

Colletotrichum orbiculare infects cucurbit but not brassica. This resistance is robust and is called nonhost resistance. We are currently analyzing Colletotrichum-Arabidopsis interactions in detail to elucidate how fungal pathogens infect and how nonhost plants defend themselves against pathogen attack at molecular level.

Dissection of fungal infection mechanism and nonhost plant resistance

C. higginsianum forms melanized infection structures called appressoria on Arabidopsis and develops penetration hyphae (Left). In contrast, C. orbiculare fails to develop penetration hyphae, although it forms appressoria (Right).

Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University 2011.5.24

virus, fungus, RNA silencing, translation, RNA replication, cell-to-cell movement, appressorium, resistance gene, non-host resistance, Nicotiana, Arabidopsis

Keywords

Recent Publications

2011 Identification of amino acids in auxiliary replicase protein p27 critical for its RNA-binding activity and the assembly of the replicase complex in Red clover necrotic mosaic virus Hyodo, K., A. Mine, H-O. Iwakawa, M. Kaido, K. Mise and T. Okuno Virology 413: 300-309, 2011

Viral cell-to-cell movement requires formation of cortical punctate structures containing Red clover necrotic mosaic virus movement protein Kaido, M., N. Funatsu, Y. Tsuno, K. Mise and T. Okuno Virology 413: 205-215, 2011

Template recognition mechanisms by replicase proteins differ between bipartite positive-strand genomic RNAs of a plant virus Iwakawa, H-O., A. Mine, K. Hyodo, M. An, M. Kaido, K. Mise and T. Okuno Journal of Virology 85: 497-509, 2011

2010 Interactions between p27 and p88 replicase proteins of Red clover necrotic mosaic virus play an essential role in viral RNA replication and suppression of RNA silencing via the 480-kDa viral replicase complex assembly Mine, A., K. Hyodo, A. Takeda, M. Kaido, K. Mise and T. Okuno Virology 407: 213-224, 2010

Entry mode-dependent function of an indole glucosinolate pathway in Arabidopsis for nonhost resistance against anthracnose pathogens Hiruma, K., M. Onozawa-Komori, F. Takahashi, M. Asakura, P. Bednarek, T. Okuno, P. Schulze-Lefert and Y. Takano Plant Cell 22: 2429-2443, 2010

A Y-shaped RNA structure in the 3’ untranslated region together with the trans-activator and core promoter of Red clover necrotic mosaic virus RNA2 is required for its negative-strand RNA synthesis An, M., H-O. Iwakawa, A. Mine, M. Kaido, K. Mise and T. Okuno Virology 405: 100-109, 2010

Identification and characterization of the 480 kDa template-specific RNA-dependent RNA polymerase complex of Red clover necrotic mosaic virus Mine, A., A. Takeda, T. Taniguchi, H. Taniguchi, M. Kaido, K. Mise and T. Okuno Journal of Virology 84: 6070-6081, 2010

Recent Publications

2009

Endoplasmic reticulum targeting of the Red clover necrotic mosaic virus movement protein is associated with the replication of viral RNA1 but not RNA2 Kaido, M., Y. Tsuno, K. Mise and T. Okuno Virology 395: 232-242, 2009

Melandrium yellow fleck virus infects Arabidopsis thaliana and has genomic RNA sequence characteristics that are unique among bromoviruses Narabayashi, T., F. Iwahashi, M. Kaido, T. Okuno and K. Mise Archives of Virology. 154: 1381-1389, 2009

Association genetics reveals three novel avirulence genes from the rice blast fungus Magnaporthe oryzae Yoshida, K., H. Saitoh, S. Fujisawa, H. Kanzaki, H. Matsumura, K. Yoshida, Y. Tosa, I. Chuma, Y. Takano, J. Win, S. Kamoun and R. Terauchi Plant Cell 21: 1573-1591, 2009

SPM1 encoding a vacuole-localized protease is required for infection-related autophagy of the rice blast fungus Magnaporthe oryzae Saitoh, H., S. Fujisawa, A. Ito, C. Mitsuoka, T. Berberich, Y. Tosa, M. Asakura, Y. Takano and R. Terauchi FEMS Microbiology Letters 300: 115-121, 2009

Host-dependent roles of the viral 5’ untranslated region (UTR) in RNA stabilization and cap-independent translational enhancement mediated by the 3’ UTR of Red clover necrotic mosaic virus RNA1 Sarawaneeyaruk, S., H-O. Iwakawaa, H. Mizumoto, H. Murakami, M. Kaido, K. Mise and T. Okuno Virology 391: 107-118, 2009

Atg26-mediated pexophagy is required for host invasion by the plant pathogenic fungus Colletotrichum orbiculare Asakura, M., S. Ninomiya, M. Sugimoto, M. Oku, S. Yamashita, T. Okuno, Y. Sakai, and Y. Takano Plant Cell 21: 1291-1304, 2009

Genetic analysis of a host determination mechanism of bromoviruses in Arabidopsis thaliana Fujisaki, K., F. Iwahashi, M. Kaido, T. Okuno and K. Mise Virus Res. 140(1-2): 103-110, 2009

2008 A viral non-coding RNA generated by cis-element-mediated protection against 5'->3' RNA decay represses both cap-independent and cap-dependent translation Iwakawa, H.-O., H. Mizumoto, H. Nagano, Y. Imoto, K. Takigawa, S. Sarawaneeyaruk, M. Kaido, K. Mise and T. Okuno J. Virol. 82(24): 10162-10174, 2008

Recent Publications

cis-Preferential requirement of a - 1 frameshift product p88 for the replication of Red clover necrotic mosaic virus RNA1 Okamoto, K., H. Nagano, H.-O. Iwakawa, H. Mizumoto, A. Takeda, M. Kaido, K. Mise and T. Okuno Virology 375(1): 205-212, 2008

2007 cis-acting core RNA elements required for negative-strand RNA synthesis and cap-independent translation are separated in the 3’-untranslated region of Red clover necrotic mosaic virus RNA1 Iwakawa, H.-O., M. Kaido, K. Mise and T. Okuno Virology 369(1): 168-181, 2007

Downregulation of the NbNACa1 gene encoding a movement-protein-interacting protein reduces cell-to-cell movement of Brome mosaic virus in Nicotiana benthamiana Kaido, M., Y. Inoue, Y. Takeda, K. Sugiyama, A. Takeda, M. Mori, A. Tamai, T. Meshi, T. Okuno and K. Mise Mol. Plant-Microbe Interact. 20(6); 671-681, 2007

Phosphorylation and interaction of the movement and coat proteins of Brome mosaic virus in infected barley protolasts Akamatsu, N., A. Takeda, M. Kishimoto, M. Kaido, T. Okuno and K. Mise Arch. Virol., 152(11); 2087-2093, 2007

2006 Cap-independent translation mechanism of Red clover necrotic mosaic virus RNA2 differs from that of RNA1 and is linked to RNA replication Mizumoto, H., H.-O. Iwakawa, M. Kaido, K. Mise and T. Okuno J. Virol. 80(8); 3781-3791, 2006

Multiple contributions of peroxisomal metabolic function to fungal pathogenicity in Colletotrichum lagenarium Asakura, M., T. Okuno, and Y. Takano Appl. Environ. Microbiol. 72(9); 6345-6354, 2006

Nonhost resistance in Arabidopsis-Colletotrichum interactions acts at the cell periphery and requires actin filament function Shimada, C., Lipka, V., O'Connell, R., Okuno, T., Schulze-Lefert, P., and Takano, Y Mol. Plant-Microbe Interact. 19(3); 270-209, 2006

A gene involved in modifying transfer RNA is required for fungal pathogenicity and stress tolerance of Colletotrichum lagenarium Takano Y, N. Takayanagi, H. Hori Y. Ikeuchi T. Suzuki, A. Kimura and T. Okuno Mol. Microbiol. 60(1); 81-92, 2006

Recent Publications

2005 A plant RNA virus suppresses RNA silencing through viral RNA replication Takeda, A., M. Tsukuda, H. Mizumoto, K. Okamoto, M. Kaido, K. Mise and T. Okuno EMBO J. 24(17); 3147-3157, 2005

The Red clover necrotic mosaic virus RNA2 trans-activator is also a cis-acting RNA2 replication element Tatsuta, M., H. Mizumoto, M. Kaido, K. Mise and T. Okuno J. Virol. 79(2); 978-986, 2005

Synthesis of infectious in vitro transcripts from Cassia yellow blotch bromovirus cDNA clones and a reassortment analysis with other bromoviruses in protoplasts Iwahashi, F., K. Fujisaki, M. Kaido, T. Okuno and K. Mise Arch. Virol. 150 (7); 1301-1314, 2005

Coat protein-independent cell-to-cell movement of bromoviruses expressing Brome mosaic virus movement protein with an adaptation-related amino acid change in the central region Sasaki, N., M. Kaido, T. Okuno and K. Mise Arch. Virol. 150(6); 1231-1240, 2005

Natural isolates of Brome mosaic virus with the ability to move from cell to cell independently of coat protein Takeda, A., W. Nakamura, N. Sasaki, K. Goto, M. Kaido, T. Okuno and K. Mise J. Gen. Virol. 86(4); 1201-1211, 2005

2004 Identification and characterization of the SSB1 locus involved in symptom development by Spring beauty latent virus infection in Arabidopsis thaliana Fujisaki, K., F. Hagihara, Y. Azukawa, M. Kaido, T. Okuno and K. Mise Mol. Plant-Microbe Interact. 17(9); 967-975, 2004

The C terminus of the movement protein of Brome mosaic virus controls the requirement for coat protein in cell-to-cell movement and plays a role in long-distance movement Takeda, A., M. Kaido, T. Okuno and K. Mise J. Gen. Virol. 85(6); 1751-1761, 2004

Effects of artificial codon changes in the movement protein gene on adaptation of a hybrid bromovirus to cowpea Sasaki, N., M. Kaido, T. Okuno and K. Mise Microbiol. Immunol. 48(2); 131-135, 2004

cAMP-PKA signaling regulates multiple steps of fungal infection cooperatively with Cmk1 MAP kinase in Colletotrichum lagenarium. Yamauchi, J., N. Takayanagi, K. Komeda, Y. Takano and T. Okuno Mol. Plant-Microbe Interact. 17(12); 1355-1365, 2004

Fungicide activity through activation of fungal signaling pathway. Kojima, K., Y. Takano, A. Yoshimi, C. Tanaka, T. Kikuchi and T. Okuno Mol. Microbiol. 53 (6); 1785-1796, 2004

Recent Publications

2003 Cap-independent translational enhancement by the 3’-untranslated region of Red clover necrotic mosaic virus RNA1 Mizumoto, H., M. Tatsuta, M. Kaido, K. Mise and T. Okuno J. Virol. 77(22); 12113-12121, 2003

cis-Acting elements required for efficient packaging of Brome mosaic virus RNA3 in barley protoplasts Damayanti, T. A., S. Tsukaguchi, K. Mise and T. Okuno J. Virol. 77(18); 9979-9986, 2003

Use of Spring beauty latent virus to identify compatible interactions between bromovirus components required for virus infection Fujisaki, K., M. Kaido, K. Mise and T. Okuno J. Gen. Virol. 84(6); 1367-1375, 2003

Characterization of a novel barley protein, HCP1, that interacts with the Brome mosaic virus coat protein Okinaka, Y., K. Mise T. Okuno and I. Furusawa Mol. Plant-Microbe Interact. 16(4); 352-359, 2003

The movement protein gene is involved in the virus-specific requirement of the coat protein in cell-to-cell movement of bromoviruses Sasaki, N., M. Arimoto, H. Nagano, M. Mori, M. Kaido, K. Mise and T. Okuno Arch. Virol. 148(4); 803-812, 2003

Complete nucleotide sequence of Spring beauty latent virus, a bromovirus infectious to Arabidopsis thaliana Fujisaki, K., F. Hagihara, M. Kaido K. Mise and T. Okuno Arch. Virol. 148(1); 165-175, 2003

Large scale parallel analysis of gene expression during infection-related morphogenesis of Magnaporthe grisea Takano, Y., W. Choi, T. K. Mitchell, T. Okuno and R. A. Dean Mol. Plant Pathol. 4(5); 337-346, 2003