• Title/Summary/Keyword: secreted proteins

Search Result 266, Processing Time 0.02 seconds

Interactions between secreted GRA proteins and host cell proteins across the parasitophorous vacuolar membrane in the parasitism of Toxoplasma gondii

  • Ahn, Hye-Jin;Kim, Sehra;Kim, Hee-Eun;Nam, Ho-Woo
    • Parasites, Hosts and Diseases
    • /
    • v.44 no.4 s.140
    • /
    • pp.303-312
    • /
    • 2006
  • Interactions between GRA proteins of dense granules in Toxoplasma gondii and host cell proteins were analyzed by yeast two-hybrid technique. The cMyc-GRA fusion proteins expressed from pGBKT7 plasmid in Y187 yeast were bound to host cell proteins from pGADT7-Rec-HeLa cDNA library transformed to AH109 yeast by mating method. By the selection procedures, a total of 939 colonies of the SD/-AHLT culture, 348 colonies of the $X-\alpha-gal$ positive and PCR, 157 colonies of the $X-\beta-gal$ assay were chosen for sequencing the cDNA and finally 90 colonies containing ORF were selected to analyze the interactions. GRA proteins interacted with a variety of host cell proteins such as enzymes, structural and functional proteins of organellar proteins of broad spectrum. Several specific bindings of each GRA protein to host proteins were discussed presumptively the role of GRA proteins after secreting into the parasitophorous vacuoles (PV) and the PV membrane in the parasitism of this parasite.

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

  • Oh, Sang-Keun;Kamoun, Sophien;Choi, Doil
    • 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.

A Study on Growth-inhibiting Protein of Human Cancer Cells Secreted from 373-L1 Cell-line (3T3-L1 세포주해서 분비하는 인체 암세포 성장억제 단백질에 대한 연구)

  • Eun, Jae-Soon;Kweon, Jin
    • Biomolecules & Therapeutics
    • /
    • v.4 no.1
    • /
    • pp.46-50
    • /
    • 1996
  • Inhibition of the growth of human cancer cells by proteins secreted from 373-L1 cells was investigated in the present study. The growth of human cancer cells was inhibited by co-culture with 373-L1 cells under 10% FBS and DME, DME, GIT and serumless medium, respectively. The conditioned medium of cultured 373-L1 cells under serumless medium was concentrated 100-fold through an ultrafiltration cell with a 10,000 molecular weight cutoff at 4$^{\circ}C$ under positive pressure using nitrogen(373-L1 EM). 373-L1 EM inhibited the growth of HeLa, Hep G 2, KHOS-Np, A43l and MCF-7 cells. 3T3-L1 EM was purified with FPLC, DEAE-ion exchange chromatography and phenyl-sepharose chromatography. The major protein of 373-L1 EM has a molecular weight of 66,000-68,000 in SDS-PAGE analysis. The results suggest that the inhibitory activity of 373-L1 EM appears to be due to some protein(m.w.66,000-68,000) secreted by 373-L1 cells.

  • PDF

IL-2-enhanced NK Cell Cytotoxicity is Regulated by Adiponectin from Hypothalamo-pituitary-adrenal Axis (Adiponectin에 의한 IL-2 증가 자연살해세포 독성의 조절)

  • Kim, Keun-Young;Yang, Young
    • IMMUNE NETWORK
    • /
    • v.6 no.1
    • /
    • pp.6-12
    • /
    • 2006
  • Background: The Hypothalamo-Pituitary-Adrenal (HPA) axis is an important regulator for the body's stress response. As a primary stress responsive system, HPA-axis secretes various neurotransmitters, hormones, and cytokines, which regulates the immune system. Natural killer (NK) cell which is plays an important role in the innate immune response, is specially decreased their numbers and loose cytolytic activity in response to stress. However, the effect of HPA-axis secreted proteins on NK cell activity has not been defined. Herein, we studied the effect of adrenal secreted adiponectin on NK cell cytotoxicity. Adiponectin which is well-known metabolic control protein, plays important roles in various diseases, including hypertension, cardiovascular diseases, inflammatory disorders, and cancer. Methods: Signal sequence trap was used to find stress novel secretory protein from HP A-axis. Selected adiponectin was treated mouse mature primary NK cells and then examined the effect of adiponectin to NK cell cytotoxicity and cytokine expression level. Results: We found that adiponectin which is secreted from adrenal gland, suppress IL-2 induced NK cell cytotoxicity. And also investigated cytolytic cytokines are suppressed by adiponectin. Conclusion: These data suggest that adiponectin inhibites NK cell cytotoxicity via suppression of cytotoxicity related target gene.

Extracellular Proteome Profiling of Bacillus pumilus SCU11 Producing Alkaline Protease for Dehairing

  • Wang, Chao;Yu, Shiqiang;Song, Ting;He, Tingting;Shao, Huanhuan;Wang, Haiyan
    • Journal of Microbiology and Biotechnology
    • /
    • v.26 no.11
    • /
    • pp.1993-2005
    • /
    • 2016
  • Bacillus pumilus is one of the most characterized microorganisms that are used for high-level production of select industrial enzymes. A novel B. pumilus SCU11 strain possessing high alkaline protease activity was obtained in our previous work. The culture supernatant of this strain showed efficient dehairing capability with minimal collagen damage, indicating promising potential applications in the leather industry. In this study, the strain's extracellular proteome was identified by LC-MS/MS-based shotgun proteomic analysis, and their related secretory pathways were characterized by BLAST searches. A total of 513 proteins, including 100 actual secreted and 413 intracellular proteins, were detected in the extracellular proteome. The functions of these secreted proteins were elucidated and four complete secretory systems (Sec, Tat, Com, and ABC transporter) were proposed for B. pumilus. These data provide B. pumilus a comprehensive extracellular proteome profile, which is a valuable theoretical and applicative basis for future genetic modifications and development of industrial enzymes.

Outer Membrane Vesicles Derived from Salmonella Enteritidis Protect against the Virulent Wild-Type Strain Infection in a Mouse Model

  • Liu, Qiong;Yi, Jie;Liang, Kang;Zhang, Xiangmin;Liu, Qing
    • Journal of Microbiology and Biotechnology
    • /
    • v.27 no.8
    • /
    • pp.1519-1528
    • /
    • 2017
  • Foodborne contamination and salmonellosis caused by Salmonella Enteritidis (S. Enteritidis) are a significant threat to human health and poultry enterprises. Outer membrane vesicles (OMVs), which are naturally secreted by gram-negative bacteria, could be a good vaccine option because they have many biologically active substances, including lipopolysaccharides (LPS), outer membrane proteins (OMPs), and phospholipids, as well as periplasmic components. In the present study, we purified OMVs derived from S. Enteritidis and analyzed their characteristics through silver staining and sodium dodecyl sulfate polyacrylamide gel electrophoresis. In total, 108 proteins were identified in S. Enteritidis OMVs through liquid chromatography tandem mass spectrometry analysis, and OMPs, periplasmic proteins, and extracellular proteins (49.9% of total proteins) were found to be enriched in the OMVs compared with bacterial cells. Furthermore, native OMVs used in immunizations by either the intranasal route or the intraperitoneal route could elicit significant humoral and mucosal immune responses and provide strong protective efficiency against a lethal dose (~100-fold $LD_{50}$) of the wild-type S. Enteritidis infection. These results indicated that S. Enteritidis OMVs might be an ideal vaccine strategy for preventing S. Enteritidis diseases.

Purification and Characterization of Two Isolectins with Arginase Activity from the Lichen Xanthoria parietina

  • Molina, M. C.;Vicente, C.
    • BMB Reports
    • /
    • v.33 no.4
    • /
    • pp.300-307
    • /
    • 2000
  • Two glycoproteins were purified and biochemically characterized from the lichen X. parietina. Both behaved as enzymes with arginase activity and haemaglutinins. Secreted arginase (SA) contained galactose and glucose in the saccharide moiety and an isoelectric point of 4.54. The algal binding-protein (ABP) had N-acetyl-glucosamine and glucose as glycosidic residues and an isoelectric point of 3.53. Both proteins had the same molecular mass (58.6 kDa) and the same qualitative amino acidic composition. The results allowed us to consider these glycoproteins as isolectins, which have significant physiological roles in the relationship between photobiont and mycobiont of symbiotic association.

  • PDF

ADAM7 Is Associated with Epididymosomes and Integrated into Sperm Plasma Membrane

  • Oh, Jeong Su;Han, Cecil;Cho, Chunghee
    • Molecules and Cells
    • /
    • v.28 no.5
    • /
    • pp.441-446
    • /
    • 2009
  • During epididymal transit, mammalian sperm acquire selected proteins secreted by the epididymis. We previously showed that a disintegrin and metalloprotease (ADAM) 7 is expressed specifically in the epididymis and transferred to the sperm surface during epididymal transit. Here, we show that mouse ADAM7 secreted to the epididymal lumen is associated with membranous vesicles known as epididymosomes. Furthermore, we found that ADAM7 can be transferred directly from epididymal vesicles to sperm and that it is an integral plasma membrane protein in sperm. Thus, our study provides new information regarding the unique mode of secretion and interaction of ADAM7 during the epididymis-to-sperm transfer process.

Proteomic Screening of Antigenic Proteins from the Hard Tick, Haemaphysalis longicornis (Acari: Ixodidae)

  • Kim, Young-Ha;Islam, Mohammad Saiful;You, Myung-Jo
    • Parasites, Hosts and Diseases
    • /
    • v.53 no.1
    • /
    • pp.85-93
    • /
    • 2015
  • Proteomic tools allow large-scale, high-throughput analyses for the detection, identification, and functional investigation of proteome. For detection of antigens from Haemaphysalis longicornis, 1-dimensional electrophoresis (1-DE) quantitative immunoblotting technique combined with 2-dimensional electrophoresis (2-DE) immunoblotting was used for whole body proteins from unfed and partially fed female ticks. Reactivity bands and 2-DE immunoblotting were performed following 2-DE electrophoresis to identify protein spots. The proteome of the partially fed female had a larger number of lower molecular weight proteins than that of the unfed female tick. The total number of detected spots was 818 for unfed and 670 for partially fed female ticks. The 2-DE immunoblotting identified 10 antigenic spots from unfed females and 8 antigenic spots from partially fed females. Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF) of relevant spots identified calreticulin, putative secreted WC salivary protein, and a conserved hypothetical protein from the National Center for Biotechnology Information and Swiss Prot protein sequence databases. These findings indicate that most of the whole body components of these ticks are non-immunogenic. The data reported here will provide guidance in the identification of antigenic proteins to prevent infestation and diseases transmitted by H. longicornis.

Studies on the Mechanisms of Gibberellic Acid Action I. Regulation of Protein Biosynthesis and Phosphorylation by Gibberellic Acid $_{3}$ (gibberellic Acid의 작용기작에 관한 연구 I. $GA_{3}$에 의한 단백질의 생합성 및 인산화반응의 조절)

  • 심웅섭
    • Journal of Plant Biology
    • /
    • v.22 no.4
    • /
    • pp.95-100
    • /
    • 1979
  • As a part of the studies on the regulatory mechanism of gene expression by $GA_{3}$ , the effects of $GA_{3}$ on the protein biosynthesis and phosphorylation in maize seedlings were investigated. 1. The optimum concentration of $GA_{3}$ for the stimulation of the protein biosynthesis was 0.3mM. 2. The protein biosynthesis was remarkably increase by $GA_{3}$ during the germination. The reason for the decrease in the protein biosynthesis by 48hrs. after germination seems to be a staggered gene expression, and/or increases in protease and RNase activities. 3. The ratio of the amount of the newly synthesized protein in germinating seeds treated with $GA_{3}$ to the amount of proteins secreted into the endosperm was similar to that ratio in control. According to this result, it seems that $GA_{3}$ stimulates only the expression of certain definite genes. 4. By the treatment with $GA_{3}$, the rates of biosynthesis and phosphorylation of proteins were increased up to about 1.5 times during germination and 6 times by 72hrs. after germination, respectively. The ratio of the total soluble proteins to the phosphorpoteins considerably increased in the early germination stage (24hrs.) but decreased after 24hrs. According to the above mentioned results, the stimulation of the phosphorylation of proteins of $GA_{3}$ seems to be attributed to the increases in the activities of protein kinases.

  • PDF