scholarly journals Putative Serine Protease Effectors of Clavibacter michiganensis Induce a Hypersensitive Response in the Apoplast of Nicotiana Species

2015 ◽  
Vol 28 (11) ◽  
pp. 1216-1226 ◽  
Author(s):  
You Lu ◽  
Noriyuki Hatsugai ◽  
Fumiaki Katagiri ◽  
Carol A. Ishimaru ◽  
Jane Glazebrook
Keyword(s):  
Nicotiana Tabacum ◽  
Enzymatic Activity ◽  
Hypersensitive Response ◽  
Serine Proteases ◽  
Host Plants ◽  
Ectopic Expression ◽  
Related Protein ◽  
Clavibacter Michiganensis ◽  
Serine Residue ◽  
Nicotiana Species

Clavibacter michiganensis subspp. michiganensis and sepedonicus cause diseases on solanaceous crops. The genomes of both subspecies encode members of the pat-1 family of putative serine proteases known to function in virulence on host plants and induction of hypersensitive responses (HR) on nonhosts. One gene of this family in C. michiganensis subsp. sepedonicus, chp-7, is required for triggering HR in Nicotiana tabacum. Here, further investigation revealed that mutation of the putative catalytic serine residue at position 232 to threonine abolished the HR induction activity of Chp-7, suggesting that enzymatic activity is required. Purified Chp-7 triggered an HR in N. tabacum leaves in the absence of the pathogen, indicating Chp-7 itself is the HR elicitor from C. michiganensis subsp. sepedonicus. Ectopic expression of chp-7 constructs in N. tabacum leaves revealed that Chp-7 targeted to the apoplast triggered an HR while cytoplasmic Chp-7 did not, indicating that Chp-7 induces the HR in the apoplast of N. tabacum leaves. Chp-7 also induced HR in N. sylvestris, a progenitor of N. tabacum, but not in other Nicotiana species tested. ChpG, a related protein from C. michiganensis subsp. michiganensis, also triggered HR in N. tabacum and N. sylvestris. Unlike Chp-7, ChpG triggered HR in N. clevelandii and N. glutinosa.

scholarly journals Clavibacter michiganensis subsp. Sepedonicus Elicits a Hypersensitive Response in Tobacco and Secretes Hypersensitive Response-Inducing Protein(s)

1997 ◽  
Vol 87 (7) ◽  
pp. 678-684 ◽  
Author(s):  
R. Nissinen ◽  
F.-M. Lai ◽  
M. J. Laine ◽  
P. J. Bauer ◽  
A. A. Reilley ◽  
...  
Keyword(s):  
Hypersensitive Response ◽  
Host Plants ◽  
Virulent Strain ◽  
Deae Cellulose ◽  
Protein S ◽  
Clavibacter Michiganensis ◽  
Bacterial Ring Rot ◽  
Clavibacter Michiganensis Subsp ◽  
Virulent Strains ◽  
Necrotic Response

Strains of Clavibacter michiganensis subsp. sepedonicus, causal agent of bacterial ring rot of potato, showed marked differences in virulence on host plants. When infiltrated into tobacco leaves, virulent strains caused a rapid localized necrotic response (within 24 to 48 h) characteristic of the hypersensitive response (HR), whereas nonpathogenic strains did not. Concentrated cell-free culture supernatants (CCS) from virulent strains caused a necrotic reaction on tobacco, whereas CCS from nonpathogenic strains did not. The necrosis-inducing activity was heat stable and protease sensitive. Inhibitors of eukaryotic metabolism suppressed the necrotic reaction of tobacco to CCS. No necrotic response was observed when host plants were infiltrated with either cells or CCS from virulent strains. HR-inducing protein(s) from a virulent strain separated from the majority of other proteins on DEAE cellulose at 250 to 300 mM NaCl. Ammonium sulfate-precipitated proteins from a virulent strain produced a necrotic reaction at a total protein concentration of 18 μg/ml, whereas those from a nonpathogenic strain did not, even at a concentration of 180 μg/ml. We conclude that virulent strains of C. michiganensis subsp. sepedonicus elicit a typical HR in tobacco and secrete proteinaceous elicitor(s) of the nonhost HR.

Expression in non-lens tissues of an enzyme activity related to the ‘lens-specific’ protein, delta crystallin

Development ◽  
1991 ◽  
Vol 111 (1) ◽  
pp. 181-190
Author(s):  
D.I. de Pomerai ◽  
W.K. Ip ◽  
M. McLaughlin ◽  
K.C. Perry
Keyword(s):  
Ectopic Expression ◽  
Molecular Size ◽  
Protein Band ◽  
Major Constituent ◽  
Lens Protein ◽  
Related Protein ◽  
Structural Protein ◽  
Cycle Enzyme ◽  
Published Evidence

When chick embryo neutral retina (NR) cells are cultured for long periods in vitro, they undergo extensive transdifferentiation into lens and express the lens protein, delta crystallin. We now demonstrate that this process is accompanied by a change in the chromatin conformation of the delta-gene locus from DNAase1-resistant to DNAase1-sensitive in the nuclei of most cells. Transcripts hybridising to a delta probe are also much more prevalent among the in vitro transcription products from lens or transdifferentiated NR culture nuclei, as compared to nuclei from fresh NR tissue. Published evidence indicates that the chick delta 1 crystallin gene encodes the major structural protein of embryonic lens fibres, whereas the closely related delta 2 gene may encode the urea-cycle enzyme argininosuccinate lyase (ASL). Our present data lends further support to this view. Both immunodetectable delta-related protein(s) and ASL activity are present in fresh embryonic NR tissue, as well as in mouse and Rana liver, and in Rana lens. Our polyclonal anti-delta antibody also cross-reacts with a major constituent of commercial bovine ASL, of the same molecular size as chick delta crystallin. Immunoselection studies suggest that the ASL activity in chick embryonic NR is conferred mainly by the delta-related protein band. So-called ‘ectopic’ expression of delta crystallin in embryonic NR (and other tissues) may thus involve the delta 2/ASL gene, and could reflect some metabolic requirement for ASL activity.

scholarly journals Molecular Characterization of the Interaction of Borrelia parkeri and Borrelia turicatae with Human Complement Regulators

2010 ◽  
Vol 78 (5) ◽  
pp. 2199-2208 ◽  
Author(s):  
Melanie Schott ◽  
Sonja Grosskinsky ◽  
Christiane Brenner ◽  
Peter Kraiczy ◽  
Reinhard Wallich
Keyword(s):  
Binding Capacity ◽  
Functional Characterization ◽  
Ectopic Expression ◽  
Factor H ◽  
Human Complement ◽  
Related Protein ◽  
Relapsing Fever ◽  
Extracellular Matrix Components ◽  
Complement Regulators

ABSTRACT In North America, tick-borne relapsing fever is caused by the species Borrelia hermsii, B. parkeri, and B. turicatae, which are transmitted to humans through the bite of the respective infected tick vectors. Here we describe the identification and functional characterization of a surface lipoprotein of B. parkeri, designated BpcA, that binds the human complement regulators factor H and factor H-related protein 1 and, simultaneously, the host protease plasminogen. In contrast, the homologous B. turicatae protein failed to bind human factor H and factor H-related protein 1 but retained its plasminogen binding capacity. Factor H bound to BpcA maintains its regulatory capacity to control C3b deposition and C3 convertase activity. Ectopic expression of BpcA in a serum-sensitive B. burgdorferi strain protects transformed cells from complement-mediated killing. Furthermore, bound plasminogen/plasmin endows B. parkeri and B. turicatae with the potential to degrade extracellular matrix components. These findings expand our understanding of the putative recent evolutionary separation of Borrelia parkeri and Borrelia turicatae, provide evidence that B. parkeri differs from B. turicatae in its ability to resist complement attack, and may help in understanding the pathological processes underlying tick-borne relapsing fever.

scholarly journals Movement pattern of Spartocera dentiventris (Berg) (Hemiptera: Coreidae) in an experimental crop of Nicotiana tabacum L. (Solanaceae)

2002 ◽  
Vol 62 (4b) ◽  
pp. 827-834 ◽  
Author(s):  
C. R. JESUS ◽  
H. P. ROMANOWSKI ◽  
L. R. REDAELLI
Keyword(s):  
Nicotiana Tabacum ◽  
Host Plants ◽  
Movement Pattern ◽  
Porto Alegre ◽  
Nicotiana Tabacum L ◽  
Mark Release Recapture ◽  
Original Plant

In the present work we investigated the movement pattern of Spartocera (=Corecoris) dentiventris (Berg) (Hemiptera: Coreidae) adults through the mark-release-recapture method in an experimental tobacco crop (Nicotiana tabacum L., Solanaceae) in Porto Alegre, RS, Brazil. We marked 217 specimens from August 1999 to April 2000. Females moved 2.94 <FONT FACE=Symbol>±</FONT> 0.198 times and males 1.46 <FONT FACE=Symbol>±</FONT> 0.171 times among host plants. The number of movements per capture was 0.53 <FONT FACE=Symbol>±</FONT>0.03 for females and 0.54 <FONT FACE=Symbol>±</FONT> 0.06 for males. Newly recruited adults took 12.75 <FONT FACE=Symbol>±</FONT> 0.919 days to leave their original plant, females moved 9.87 <FONT FACE=Symbol>±</FONT> 0.711 m and males 9.16 <FONT FACE=Symbol>±</FONT> 1.29 m in this first movement. We estimate that females move an average of 26.22 m and males 13.89 m during their permanence in the area.

The serpin proteinase inhibitor 8: An endogenous furin inhibitor released from human platelets

2006 ◽  
Vol 95 (02) ◽  
pp. 243-252 ◽  
Author(s):  
Julie Leblond ◽  
Marie-Hélène Laprise ◽  
Simon Gaudreau ◽  
Francine Grondin ◽  
Walter Kisiel ◽  
...  
Keyword(s):  
Enzymatic Activity ◽  
Proteinase Inhibitor ◽  
Serine Proteases ◽  
Antithrombin Iii ◽  
Direct Interaction ◽  
Human Platelets ◽  
Stable Complex ◽  
Functional Responses ◽  
Pai 1 ◽  
Platelet Functions

SummaryThe cornerstone of hemostasis is the ability of the organism to limit the enzymatic processes involved, thereby avoiding thrombosis. For this, anticoagulant systems in place involve serpins, such as PAI-1 and antithrombin III, which bind to their targeted serine proteases and limit their period of activity. We have previously identified the serine protease furin as a platelet-derived enzyme with an intrinsic role in platelet functions. We now report that furin enzymatic activity decreased rapidly following platelet activation, corresponding with the increase in formation of a high 180 M r SDS-stable complex composed of furin and the PI8 serpin. PI8 is shown to be a platelet-derived constituent, synthesized by megakaryocytes and stored in platelets prior to its release. Immunoprecipitation and purification of the PI8-furin complex confirmed their direct interaction and indicates that one of the roles of PI8 is to inhibit furin enzymatic activity. Furthermore, our findings demonstrate the inhibitory capacity of exogenous PI8 in platelet aggregation assays. The finding that PI8 is released by platelets and controls functional responses suggests a role for this serpin in platelet-regulated pathophysiological responses.

scholarly journals Heterologous Movement Protein Strongly Modifies the Infection Phenotype of Cucumber Mosaic Virus

2002 ◽  
Vol 76 (7) ◽  
pp. 3554-3557 ◽  
Author(s):  
Emese Huppert ◽  
Dénes Szilassy ◽  
Katalin Salánki ◽  
Zoltán Divéki ◽  
Ervin Balázs
Keyword(s):  
Nicotiana Tabacum ◽  
Virus Infection ◽  
Cucumber Mosaic Virus ◽  
Mosaic Virus ◽  
Host Plants ◽  
Movement Protein ◽  
Long Distance ◽  
Cucumber Mosaic Cucumovirus ◽  
Nicotiana Debneyi ◽  
Symptom Phenotype

ABSTRACT A hybrid virus (CMVcymMP) constructed by replacing the movement protein (MP) of cucumber mosaic cucumovirus (CMV) with that of cymbidium ringspot tombusvirus (CymRSV) was viable and could efficiently spread both cell to cell and long distance in host plants. The hybrid virus was able to move cell to cell in the absence of functional CP, whereas CP-deficient CMV was restricted to single inoculated cells. In several Chenopodium and Nicotiana species, the symptom phenotype of the hybrid virus infection was clearly determined by the foreign MP gene. In Nicotiana debneyi and Nicotiana tabacum cv. Xanthi, the hybrid virus could move systemically, contrary to CymRSV.

scholarly journals Polyamine synthesis and accumulation in the hypersensitive response to TMV in Nicotiana tabacum

1997 ◽  
Vol 135 (3) ◽  
pp. 467-473 ◽  
Author(s):  
PATRIZIA TORRIGIANI ◽  
ANNA LAURA RABITI ◽  
CRISTINA BORTOLOTTI ◽  
LUCIETTA BETTI ◽  
FRANCESCA MARANI ◽  
...  
Keyword(s):  
Nicotiana Tabacum ◽  
Hypersensitive Response ◽  
Polyamine Synthesis

Isolation of the genomic clone for pathogenesis-related protein 1a from Nicotiana tabacum cv. Xanthi-nc

1988 ◽  
Vol 11 (2) ◽  
pp. 89-94 ◽  
Author(s):  
George Payne ◽  
T. Dawn Parks ◽  
William Burkhart ◽  
Sandra Dincher ◽  
Patricia Ahl ◽  
...  
Keyword(s):  
Nicotiana Tabacum ◽  
Genomic Clone ◽  
Related Protein ◽  
Pathogenesis Related Protein ◽  
Pathogenesis Related

scholarly journals Identification of Two Novelhrp-Associated Genes in the hrp Gene Cluster ofXanthomonas oryzae pv. oryzae

2000 ◽  
Vol 182 (7) ◽  
pp. 1844-1853 ◽  
Author(s):  
Weiguang Zhu ◽  
Mark M. MaGbanua ◽  
Frank F. White
Keyword(s):  
Nucleotide Sequence ◽  
Gene Cluster ◽  
Hypersensitive Response ◽  
Xanthomonas Campestris ◽  
Host Plants ◽  
Xanthomonas Oryzae ◽  
Insertion Element ◽  
Nonhost Plant ◽  
Rice Leaves ◽  
Glycine Rich Protein

ABSTRACT We have cloned a hrp gene cluster fromXanthomonas oryzae pv. oryzae. Bacteria with mutations in the hrp region have reduced growth in rice leaves and lose the ability to elicit a hypersensitive response (HR) on the appropriate resistant cultivars of rice and the nonhost plant tomato. A 12,165-bp portion of nucleotide sequence from the presumed left end and extending through the hrpB operon was determined. The region was most similar to hrp genes from Xanthomonas campestris pv. vesicatoria and Ralstonia solanacearum. Two new hrp-associated loci, namedhpa1 and hpa2, were located beyond thehrpA operon. The hpa1 gene encoded a 13-kDa glycine-rich protein with a composition similar to those of harpins and PopA. The product of hpa2 was similar to lysozyme-like proteins. Perfect PIP boxes were present in the hrpB andhpa1 operons, while a variant PIP box was located upstream of hpa2. A strain with a deletion encompassinghpa1 and hpa2 had reduced pathogenicity and elicited a weak HR on nonhost and resistant host plants. Experiments using single mutations in hpa1 and hpa2indicated that the loss of hpa1 was the principal cause of the reduced pathogenicity of the deletion strain. A 1,519-bp insertion element was located immediately downstream of hpa2. Hybridization with hpa2 indicated that the gene was present in all of the strains of Xanthomonas examined. Hybridization experiments with hpa1 and IS1114indicated that these sequences were detectable in all strains ofX. oryzae pv. oryzae and some other Xanthomonasspecies.

scholarly journals Ectopic Expression of Xylella fastidiosa rpfF Conferring Production of Diffusible Signal Factor in Transgenic Tobacco and Citrus Alters Pathogen Behavior and Reduces Disease Severity

2017 ◽  
Vol 30 (11) ◽  
pp. 866-875 ◽  
Author(s):  
R. Caserta ◽  
R. R. Souza-Neto ◽  
M. A. Takita ◽  
S. E. Lindow ◽  
A. A. De Souza
Keyword(s):  
Transgenic Tobacco ◽  
Disease Severity ◽  
Host Plants ◽  
Xylella Fastidiosa ◽  
Ectopic Expression ◽  
Signal Molecules ◽  
Insect Vector ◽  
Expression Of Genes ◽  
Diffusible Signal Factor ◽  
Population Sizes

The pathogenicity of Xylella fastidiosa is associated with its ability to colonize the xylem of host plants. Expression of genes contributing to xylem colonization are suppressed, while those necessary for insect vector acquisition are increased with increasing concentrations of diffusible signal factor (DSF), whose production is dependent on RpfF. We previously demonstrated that transgenic citrus plants ectopically expressing rpfF from a citrus strain of X. fastidiosa subsp. pauca exhibited less susceptibility to Xanthomonas citri subsp. citri, another pathogen whose virulence is modulated by DSF accumulation. Here, we demonstrate that ectopic expression of rpfF in both transgenic tobacco and sweet orange also confers a reduction in disease severity incited by X. fastidiosa and reduces its colonization of those plants. Decreased disease severity in the transgenic plants was generally associated with increased expression of genes conferring adhesiveness to the pathogen and decreased expression of genes necessary for active motility, accounting for the reduced population sizes achieved in the plants, apparently by limiting pathogen dispersal through the plant. Plant-derived DSF signal molecules in a host plant can, therefore, be exploited to interfere with more than one pathogen whose virulence is controlled by DSF signaling.

Sign in / Sign up

Export Citation Format

Share Document