• Journal of Microbiology and Biotechnology
• /
• v.27 no.1
• /
• pp.171-178
• /
• 2017

A series of novel effector molecules secreted by the type three secretion system (T3SS) of Shigella spp. have been reported in recent years. In this study, a proteomic approach was applied to study T3SS effectors systematically. First, proteins secreted by the S. flexneri wild-type strain after Congo Red induction were separated and identified using two-dimensional electrophoresis to display the relative abundance of all kinds of early effectors for the first time. Then, a gene deletion mutant of known virulence repressor (OspD1) and a gene overexpressed mutant of two known virulence activators (MxiE and IpgC) were constructed and analyzed to discover potential late effectors. Furthermore, the supernatant proteins of gene deletion mutants of two known translocators (IpaB and IpaD), which would constantly secrete effectors, were also analyzed. Among all of the secreted proteins identified in our study, IpaH1.4, IpaH_5, and IpaH_7 have not been reported before. These proteomics data of the secreted effectors will be valuable to understand the pathogenesis of S. flexneri.

• The Plant Pathology Journal
• /
• v.26 no.3
• /
• pp.209-215
• /
• 2010

Plant pathogenic oomycetes, such as Phytophthora spp., are the causal agent of the most devastating plant diseases. During infection, these pathogens accomplish parasitic colonization of plants by modulating host defenses through an array of disease effector proteins. These effectors are classified in two classes based on their target sites in the host plant. Apoplastic effectors are secreted into the plant extracellular space, and cytoplasmic effectors are translocated inside the plant cell, through the haustoria that enter inside living host cell. Recent characterization of some oomycete Avr genes showed that they encode effector protein with general modular structure including N-terminal conserved RXLR-DEER motif. More detailed evidences suggest that these AVR effectors are secreted by the pathogenic oomycetes and then translocated into the host plant cell during infection. Recent findings indicated that one of the P. infestans effector, Avrblb2, specifically induces hypersensitive response (HR) in the presence of Solanum bulbocastanum late blight resistance genes Rpi-blb2. On the other hand, another secreted RXLR protein PexRD8 originated from P. infestans suppressed the HCD triggered by the elicitin INF1. In this review, we described recent progress in characterized RXLR effectors in Phytophthora spp. and their dual functions as modulators of host plant immunity.

• Journal of the Korea Society of Computer and Information
• /
• v.22 no.7
• /
• pp.83-91
• /
• 2017

In this paper, we propose a thorough solution for adjusting virtual sound field with different kinds of devices and software in preliminary procedure and late stage of music processing. The basic process of music production includes composing, arranging and recording at pre-production stage as well as sound mixing and mastering at post-production stage. At the initial stage of music creation, it should be checked whether the design of virtual sound field, the choice of the tone and the instrument used in the arrangement match the virtual sound field required for the final work. In later recording, mixing and mastering, elaborate adjustments should be done to the virtual sound field. This study also analyzed how to apply the parameter of the effectors to the design and adjustment of the virtual sound field, making it the source of our creation.

• 한국균학회소식:학술대회논문집
• /
• 2015.11a
• /
• pp.26-26
• /
• 2015

Phytophthora infestans is the causal agent of potato and tomato late blight, one of the most devastating plant diseases. P. infestans secretes effector proteins that are both modulators and targets of host plant immunity. Among these are the so-called RXLR effectors that function inside plant cells and are characterized by a conserved motif following the N-terminal signal peptide. In contrast, the effector activity is encoded by the C terminal region that follows the RXLR domain. Recently, I performed in planta functional profiling of different RXLR effector alleles. These genes were amplified from a variety of P. infestans isolates and cloned into a Potato virus X (PVX) vector for transient in planta expression. I assayed for R-gene specific induction of hypersensitive cell death. The findings included the discovery of new effector with avirulence activity towards the Solanum bulbocastanum Rpi-blb2 resistance gene. The Rpi-blb2 encodes a protein with a putative CC-NBS-LRR (a coiled-coil-nucleotide binding site and leucine-rich repeat) motif that confers Phytophthora late blight disease resistance. We examined the components required for Rpi-blb2-mediated resistance to P. infestans in Nicotiana benthamiana. Virus-induced gene silencing was used to repress candidate genes in N. benthamiana and to assay against P. infestans infections. NbSGT1 was required for disease resistance to P. infestans and hypersensitive responses (HRs) triggered by co-expression of AVRblb2 and Rpi-blb2 in N. benthamiana. RAR1 and HSP90 did not affect disease resistance or HRs in Rpi-blb2-transgenic plants. To elucidate the role of salicylic acid (SA) in Rpi-blb2-mediated resistance, we analyzed the response of NahG-transgenic plants following P. infestans infection. The increased susceptibility of Rpi-blb2-transgenic plants in the NahG background correlated with reduced SA and SA glucoside levels. Furthermore, Rpi-blb2-mediated HR cell death was associated with $H_2O_2$, but not SA, accumulation. SA affects basal defense and Rpi-blb2-mediated resistance against P. infestans. These findings provide evidence about the roles of SGT1 and SA signaling in Rpi-blb2-mediated resistance against P. infestans.

• Development and Reproduction
• /
• v.27 no.2
• /
• pp.67-75
• /
• 2023

Polymeric immunoglobulin receptor (pIgR) mediates the transfer of polymeric immunoglobulin to protect organisms and is one of the most important mucosal effectors. In this study, the developmental stage- and tissue-specific expression of pIgR were observed before virus inoculation in olive flounder. pIgR was gradually expressed until the formation of immune tissue, exhibiting high expression in the late juvenile period; thereafter, pIgR expression gradually decreased and exhibited high expression in the spleen and skin. Moreover, pIgR expression after viral hemorrhagic septicemia virus infection was high in the kidney and spleen tissues at high density and low at low density. The results of this study can provide a basis for future studies on breeding density, virus expression, and immune system studies in fish.