• 제목/요약/키워드: Effectors

검색결과 163건 처리시간 0.025초

Nuclear Effectors in Plant Pathogenic Fungi

  • Surajit De Mandal;Junhyun Jeon
    • Mycobiology
    • /
    • 제50권5호
    • /
    • pp.259-268
    • /
    • 2022
  • The nuclear import of proteins is a fundamental process in the eukaryotes including plant. It has become evident that such basic process is exploited by nuclear effectors that contain nuclear localization signal (NLS) and are secreted into host cells by fungal pathogens of plants. However, only a handful of nuclear effectors have been known and characterized to date. Here, we first summarize the types of NLSs and prediction tools available, and then delineate examples of fungal nuclear effectors and their roles in pathogenesis. Based on the knowledge on NLSs and what has been gleaned from the known nuclear effectors, we point out the gaps in our understanding of fungal nuclear effectors that need to be filled in the future researches.

Proteomic Analysis of Shigella Virulence Effectors Secreted under Different Conditions

  • Liu, Xingming;Lu, Lilan;Liu, Xinrui;Liu, Xiankai;Pan, Chao;Feng, Erling;Wang, Dongshu;Niu, Chang;Zhu, Li;Wang, Hengliang
    • Journal of Microbiology and Biotechnology
    • /
    • 제27권1호
    • /
    • 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.

Oomycetes RXLR Effectors Function as Both Activator and Suppressor of Plant Immunity

  • Oh, Sang-Keun;Kamoun, Sophien;Choi, Doil
    • The Plant Pathology Journal
    • /
    • 제26권3호
    • /
    • 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.

Molecular determinants of the host specificity by Xanthomonas spp.

  • Heu, Sunggi;Choi, Min-Seon;Park, Hyoung-Joon;Lee, Seung-Don;Ra, Dong-Soo
    • 한국식물병리학회:학술대회논문집
    • /
    • 한국식물병리학회 2004년도 The 2004 KSPP Annual Meeting & International Symposium
    • /
    • pp.65-67
    • /
    • 2004
  • During initial interactions of bacteria with their host plants, most plants recognize the bacterial infections and repel the pathogen by plant defense mechanism. The most active plant defense mechanism is the hypersensitive response (HR) which is the localized induced cell death in the plant at the site of infection by a pathogen. A primary locus induced in gram-negative phytopathogenic bacteria during this initial interaction is the Hrp locus. The Hrp locus is composed of a cluster of genes that encodes the bacteral Type 111 machinery that is involved in the secretion and translocation of effector proteins to the plant cell. DNA sequence analysis of hrp gene in phytopathogenic bacteria has revealed a Hrp pathogenicity is]and (PAI) with a tripartite mosaic structure. For many gram-negative pathogenic bacteria, colonization of the host's tissue depends on the type III protein secretion system (TTSS) which secrets and translocates effector proteins into the host cell. Effectors can be divided into several groups including broad host range effectors, host specific effectors, disease specific effectors, and effectors inhibit host defenses. The role of effectors carrying LRR domain in plant resistance is very elusive since most known plant resistance gene carry LRR domain. Host specific effectors such as several avr gene products are involved in the determination of the host specificity. Almost all the phytopathogenic Xanthomonas spp. carry avrBs1, avrBs2, and avrBs3 homologs. Some strains of X. oryzae pv. oryzae carry more than 10 copies of avrBs3 homologs. However, the functions of all those avr genes in host specificity are not characterized well.;

  • PDF

Mini-review: oomycete RXLR genes as effector-triggered immunity

  • Arif, Saima;Jang, Hyun A;Kim, Mi-Reu;Oh, Sang-Keun
    • 농업과학연구
    • /
    • 제45권4호
    • /
    • pp.561-573
    • /
    • 2018
  • Oomycetes are known to secrete a vast arsenal of effectors that modulate the host defense system as well as facilitate establishing a parasitic infection in plants. In recent years, tremendous progress has been made in the field of effectromics based on studies of oomycetes, especially the cytoplasmic family of RXLR effectors. Yet, the biology of the RXLR effector family is still poorly understood. There has been a consensus regarding the structure of the RXLR motif in the mycologist community. However, the function of the RXLR motif is still unclear. First, different models have suggested that the role of the RXLR motif is either in translocation to a target destination inside a host cell or in the cleavage of itself followed by secretion. Second, recent studies have suggested different functional models for the RXLR motif. According to a widely accepted model, the RXLR motif is directly involved in the translocation of effectors to target sites. In contrast, a new study has proposed that the RXLR motif is involved in secretion rather than translocation. Thus, this review is an attempt to summarize the recent advances made in the functional analysis of the N-terminal domain of RXLR effectors.

Construction of Comprehensive Metabolic Network for Glycolysis with Regulation Mechanisms and Effectors

  • JIN, JONG-HWA;JUNG, UI-SUB;JAE, WOOK-NAM;IN, YONG-HO;LEE, SANG-YUP;LEE, DOHE-ON;LEE, JIN-WON
    • Journal of Microbiology and Biotechnology
    • /
    • 제15권1호
    • /
    • pp.161-174
    • /
    • 2005
  • Abstract Glycolysis has a main function to provide ATP and precursor metabolites for biomass production. Although glycolysis is one of the most important pathways in cellular metabolism, the details of its regulation mechanism and regulating chemicals are not well known yet. The regulation of the glycolytic pathway is very robust to allow for large fluxes at almost constant metabolite levels in spite of changing environmental conditions and many reaction effectors like inhibitors, activating compounds, cofactors, and related metal ions. These changing environmental conditions and metabolic reaction effectors were focused on to understand their roles in the metabolic networks. In this study, we have investigated for construction of the regulatory map of the glycolytic metabolic network and tried to collect all the effectors as much as possible which might affect the glycolysis metabolic pathway. Using the results of this study, it is expected that a complex metabolic situation can be more precisely analyzed and simulated by using available programs and appropriate kinetic data.

Characterization of Phytophthora capsici effector genes and their functional repertoire

  • Arif, Saima;Lim, Gi Taek;Kim, Sun Ha;Oh, Sang-Keun
    • 농업과학연구
    • /
    • 제48권3호
    • /
    • pp.643-654
    • /
    • 2021
  • Phytophthora capsici is one of the most destructive hemibiotrophic pathogens; it can cause blight in chili peppers, and secrete various effector proteins to infect the plants. These effectors contain an N-terminal conserved RXLR motif. Here, we generated full-length RXLR effector coding genes using primer pairs, and cloned them into the pGR106 vector for in planta expression. Two of these genes, PcREK6 and PcREK41 (P. capsici RXLR effector from the Korea isolate), were further characterized. PcREK6 and PcREK41 genes showed that they encode effector proteins with a general modular structure, including the N-terminal conserved RXLR-DEER motif and signal peptide sequences. PcREK6 and PcREK41 expressions were strongly induced when the chili pepper plants (Capsicum annuum) were challenged with P. capsici. These results provide molecular evidence to elucidate the virulence or avirulence factors in chili pepper. Our results also showed that two effectors induce hypersensitive response (HR) cell death when expressed in chili leaves. Cell death suppression assays in Nicotiana benthamiana revealed that most effectors could not suppress programmed cell death (PCD) triggered by Bcl-associated X (BAX) or Phytophthora infestans elicitin (INF1). However, PcREK6 fully suppressed PCD triggered by BAX, while PcREK41 partially suppressed PCD triggered by INF1 elicitin. These results suggest that PcREK effectors from P. capsici interact with putative resistance (R) proteins in planta, and different effectors may target different pathways in a plant cell to suppress pattern-triggered immunity (PTI) or effector-triggered immunity (ETI).

교각 기둥시공을 위한 매니퓰레이터 엔드 이펙터 설계 (Design of Manipulator End Effectors for Pier Column Construction)

  • 정태일;이상원;이상윤;유지환
    • 로봇학회논문지
    • /
    • 제16권3호
    • /
    • pp.207-215
    • /
    • 2021
  • There is a risk of serious injury to workers who work at height in pier construction process. By using auto climbing formwork system that does not need to dismantle and reinstall formworks, it is possible to improve work efficiency and safety of workers. However, auto climbing formwork system still requires workers to work on a pier for rebar connection works and so on. In order to eliminate works by workers on the pier, robot manipulators with special end effectors are proposed. Through analysis of works on the pier, three specialized end effectors which are a gripper, a rebar coupler press, and a concrete vibrator, are suggested. Also, new pier construction scenario by the suggested system is confirmed using 3d modeling. It is expected that the proposed system and method enables pier construction without workers on piers. It will increase safety and efficiency of pier construction.

Depolarizing Effectors of Bradykinin Signaling in Nociceptor Excitation in Pain Perception

  • Choi, Seung-In;Hwang, Sun Wook
    • Biomolecules & Therapeutics
    • /
    • 제26권3호
    • /
    • pp.255-267
    • /
    • 2018
  • Inflammation is one of the main causes of pathologic pain. Knowledge of the molecular links between inflammatory signals and pain-mediating neuronal signals is essential for understanding the mechanisms behind pain exacerbation. Some inflammatory mediators directly modulate the excitability of pain-mediating neurons by contacting the receptor molecules expressed in those neurons. For decades, many discoveries have accumulated regarding intraneuronal signals from receptor activation through electrical depolarization for bradykinin, a major inflammatory mediator that is able to both excite and sensitize pain-mediating nociceptor neurons. Here, we focus on the final effectors of depolarization, the neuronal ion channels, whose functionalities are specifically affected by bradykinin stimulation. Particular G-protein coupled signaling cascades specialized for each specific depolarizer ion channels are summarized. Some of these ion channels not only serve as downstream effectors but also play critical roles in relaying specific pain modalities such as thermal or mechanical pain. Accordingly, specific pain phenotypes altered by bradykinin stimulation are also discussed. Some members of the effector ion channels are both activated and sensitized by bradykinin-induced neuronal signaling, while others only sensitized or inhibited, which are also introduced. The present overview of the effect of bradykinin on nociceptor neuronal excitability at the molecular level may contribute to better understanding of an important aspect of inflammatory pain and help future design of further research on the components involved and pain modulating strategies.