176 research outputs found
Interaction between viral RNA silencing suppressors and host factors in plant immunity
No full textTo elucidate events in the molecular arms race between the host and pathogen in evaluating plant immunity, a zigzag model is useful for uncovering aspects common to different host-pathogen interactions. By analogy of the steps in virus-host interactions with the steps in the standard zigzag model outlined in recent papers, we may regard RNA silencing as pattern-triggered immunity (PTI) against viruses, RNA silencing suppressors (RSSs) as effectors to overcome host RNA silencing and resistance gene (R-gene)-mediated defense as effector-triggered immunity (ETI) recognizing RSSs as avirulence proteins. However, because the standard zigzag model does not fully apply to some unique aspects in the interactions between a plant host and virus, we here defined a model especially designed for viruses. Although we simplified the phenomena involved in the virus-host interactions in the model, certain specific interactive steps can be explained by integrating additional host factors into the model. These host factors are thought to play an important role in maintaining the efficacy of the various steps in the main pathway of defense against viruses in this model for virus-plant interactions. For example, we propose candidates that may interact with viral RSSs to induce the resistance response
Detection and Characterization of Mycoviruses in Arbuscular Mycorrhizal Fungi by Deep-Sequencing
No full textFungal viruses (mycoviruses) often have a significant impact not only on phenotypic expression of the host fungus but also on higher order biological interactions, e.g., conferring plant stress tolerance via an endophytic host fungus. Arbuscular mycorrhizal (AM) fungi in the phylum Glomeromycota associate with most land plants and supply mineral nutrients to the host plants. So far, little information about mycoviruses has been obtained in the fungi due to their obligate biotrophic nature. Here we provide a technical breakthrough, “two-step strategy” in combination with deep-sequencing, for virological study in AM fungi; dsRNA is first extracted and sequenced using material obtained from highly productive open pot culture, and then the presence of viruses is verified using pure material produced in the in vitro monoxenic culture. This approach enabled us to demonstrate the presence of several viruses for the first time from a glomeromycotan fungus
Virus induced gene silencing in Antirrhinum majus using the Cucumber mosaic virus vector : Functional analysis of the AINTEGUMENTA (Am-ANT) gene of A. majus
No full textThe Arabidopsis gene AINTEGUMENTA (At-ANT) functions in cell proliferation and organ growth. The ANT protein has two copies of the AP2 domains, R1 and R2. Recently, a partial cDNA sequence of the At-ANT homolog in Antirrhinum majus (Am-ANT) was reported (Delgado-Benarroch et al., 2009). Here, we used virus-induced gene silencing (VIGS) to analyze the function of the reported Am-ANT. We then determine the open reading frame (ORF) of Am-ANT and its predicted amino acid sequence. We induced VIGS using Cucumber mosaic virus (CMV-A1) and suppressed the level of Am-ANT mRNA and noted any phenotypic changes. The function of Am-ANT was very similar to that of At-ANT. The A1:ANT-infected Antirrhinum plants had smaller floral organs and leaves, even though cell sizes were unchanged in flowers and larger in leaves. The CMV-based VIGS showed that the cloned Am-ANT gene was indeed functional in cell proliferation and organ growth as observed for At-ANT. In A. majus, CMV vector provide great advantages for analysis of gene functions
Activation of nucleotide-binding oligomerization domain 2 by muramyl dipeptide negatively regulates Toll-like receptor 9-mediated colonic inflammation through the induction of deubiquitinating enzyme A expression
No full text主査：岡田 斉 教授
学内授与番号：医第1425号This is a pre-copyedited, author-produced version of an article accepted for publication in [International Immunology] following peer review. The version of record [Yasuhiro Masuta, Kosuke Minaga, Masayuki Kurimoto, Ikue Sekai, Akane Hara, Naoya Omaru, Natsuki Okai, Yasuo Otsuka, Ryutaro Takada, Tomoe Yoshikawa, Sho Masaki, Ken Kamata, Hajime Honjo, Yasuyuki Arai, Kouhei Yamashita, Masatoshi Kudo, Tomohiro Watanabe "Activation of nucleotide-binding oligomerization domain 2 by muramyl dipeptide negatively regulates Toll-like receptor 9-mediated colonic inflammation through the induction of deubiquitinating enzyme A expression" International Immunology, Volume 35, Issue 2, February 2023, Pages 79–94] is available online at: [https://doi.org/10.1093/intimm/dxac045]
- …
