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3.
Mol Phylogenet Evol ; 111: 158-168, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28390910

ABSTRACT

High throughput sequencing technologies have revolutionized the potential to reconcile incongruence between gene and species trees, and numerous approaches have been developed to take advantage of these advances. Genotyping-by-sequencing is becoming a regular tool for gathering phylogenetic data, yet comprehensive evaluations of phylogenetic methods using these data are sparse. Here we use multiple phylogenetic and population genetic methods for genotyping-by-sequencing data to assess species relationships in a group of forest insect pests, the spruce budworm (Choristoneura fumiferana) species complex. With few exceptions, all methods agree on the same relationships, most notably placing C. pinus as basal to the remainder of the group, rather than C. fumiferana as previously suggested. We found strong support for the monophyly of C. pinus, C. fumiferana, and C. retiniana, but more ambiguous relationships and signatures of introgression in a clade of western lineages, including C. carnana, C. lambertiana, C. occidentalis occidentalis, C. occidentalis biennis, and C. orae. This represents the most taxonomically comprehensive genomic treatment of the spruce budworm species group, which is further supported by the broad agreement among multiple methodologies.


Subject(s)
Genome, Insect , Moths/genetics , Phylogeny , Polymorphism, Single Nucleotide/genetics , Animals , Discriminant Analysis , Genetic Speciation , Genetics, Population , Genotype , Geography , North America , Principal Component Analysis , Sequence Analysis, DNA , Species Specificity , United States
4.
Ecology ; 97(11): 3243, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27870054

ABSTRACT

This dataset provides growth form classifications for 67,413 vascular plant species from North, Central, and South America. The data used to determine growth form were compiled from five major integrated sources and two original publications: the Botanical Information and Ecology Network (BIEN), the Plant Trait Database (TRY), the SALVIAS database, the USDA PLANTS database, Missouri Botanical Garden's Tropicos database, Wright (2010), and Boyle (1996). We defined nine plant growth forms based on woodiness (woody or non-woody), shoot structure (self-supporting or not self-supporting), and root traits (rooted in soil, not rooted in soil, parasitic or aquatic): Epiphyte, Liana, Vine, Herb, Shrub, Tree, Parasite, or Aquatic. Species with multiple growth form classifications were assigned the growth form classification agreed upon by the majority (>2/3) of sources. Species with ambiguous or otherwise not interpretable growth form assignments were excluded from the final dataset but are made available with the original data. Comparisons with independent estimates of species richness for the Western hemisphere suggest that our final dataset includes the majority of New World vascular plant species. Coverage is likely more complete for temperate than for tropical species. In addition, aquatic species are likely under-represented. Nonetheless, this dataset represents the largest compilation of plant growth forms published to date, and should contribute to new insights across a broad range of research in systematics, ecology, biogeography, conservation, and global change science.


Subject(s)
Plant Development , Plants/classification , Central America , Demography , North America , South America , Species Specificity
5.
J Antimicrob Chemother ; 70(10): 2718-24, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26142479

ABSTRACT

OBJECTIVES: Ireland has the highest rate of vancomycin-resistant Enterococcus faecium (VREfm) isolated from blood of nosocomial patients in Europe, which rose from 33% (110/330) in 2007 to 45% (178/392) in 2012. No other European country had a VREfm rate from blood cultures of >25%. Our aim was to elucidate the reasons for this significantly higher rate in Ireland. METHODS: The epidemiology and molecular typing of VRE from bloodstream infections (BSIs) was examined in a tertiary care referral hospital and isolates were compared with those from other tertiary care referral centres in the region. RESULTS: The most common source of VRE BSIs was intra-abdominal sepsis, followed by line-related infection and febrile neutropenia. Most of the isolates were positive for vanA; 52% (43/83) possessed the esp gene and 12% (10/83) possessed the hyl gene. Genotyping by SmaI macrorestriction analysis (PFGE) of isolates revealed clonal relatedness between bloodstream isolates and environmental isolates. VRE BSI isolates from two other tertiary care hospitals in the Dublin region showed relatedness by PFGE analysis. MLST revealed four STs (ST17, ST18, ST78 and ST203), all belonging to the clonal complex of hospital-associated strains. CONCLUSIONS: Irish VRE BSI isolates have virulence factor profiles as previously reported from Europe. Typing analysis shows the spread of individual clones within the hospital and between regional tertiary care hospitals. Apart from transmission of VRE within the hospital and transfer of colonized patients between Irish hospitals, no other explanation for the persistently high VREfm BSI rate in Ireland has been found.


Subject(s)
Bacteremia , Cross Infection , Enterococcus faecium/drug effects , Enterococcus faecium/genetics , Gram-Positive Bacterial Infections/epidemiology , Gram-Positive Bacterial Infections/microbiology , Tertiary Care Centers , Vancomycin Resistance , Adult , Aged , Aged, 80 and over , Cluster Analysis , Enterococcus faecium/classification , Female , Gram-Positive Bacterial Infections/mortality , Humans , Ireland/epidemiology , Male , Middle Aged , Molecular Typing , Young Adult
6.
Analyst ; 140(20): 6775-81, 2015 Oct 21.
Article in English | MEDLINE | ID: mdl-26205889

ABSTRACT

There is an ever increasing need to develop new tools to aid in the diagnosis and monitoring of human diseases. Such tools will ultimately reduce the cost of healthcare by identifying disease states more quickly and cheaply than current practices. One method showing promise is the analysis of gas-phase biomarkers from human breath, urine, sweat and stool that reflect bodily metabolism. Analysis of these volatiles by GC MS requires specialised infra-structure and staff, making it unsuitable for a clinical setting. Point of care sensor based technologies such as eNoses often suffer from stability and sensitivity issues. Field-Asymmetric Ion Mobility Spectrometry (FAIMS) has potential to fulfil this clinical need. In this paper we review the medical need, the technology, sampling methods and medical evidence thus far. We conclude with reflecting on future developmental steps necessary to bring the device into medical practice.


Subject(s)
Diagnostic Techniques and Procedures , Gases/chemistry , Mass Spectrometry/methods , Diagnostic Techniques and Procedures/instrumentation , Humans , Mass Spectrometry/instrumentation
7.
J Hosp Infect ; 90(2): 108-16, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25935700

ABSTRACT

BACKGROUND: Recurrent Clostridium difficile infection (CDI) represents a significant healthcare challenge. Patients may suffer multiple episodes of CDI with the index strain (relapse) or become infected by another strain acquired nosocomially (reinfection). AIM: We aimed to characterize C. difficile isolates causing recurrent CDI at a tertiary referral hospital by whole-genome sequencing (WGS) to assess strain similarities at the highest level of genetic resolution and accurately detect relapse, reinfection, and putative strain transmission events. METHODS: An 18-month prospective study of recurrent CDI was undertaken. Clostridium difficile was cultured from stool samples collected longitudinally from any patients suffering ≥2 clinically defined CDI episodes. Patient demographics and clinical data were recorded, and strain relatedness investigated by both polymerase chain reaction (PCR)-based ribotyping and WGS. FINDINGS: Nineteen patients were identified with ≥2 clinically defined CDI episodes who cumulatively suffered 39 recurring CDI episodes (58 total episodes). Patients had a median length of stay (LOS) of 144 days and experienced between two and seven CDI episodes. Ribotyping indicated 27 apparent same-strain relapses, five reinfections and the predominance of ribotypes 078 (ST-11) and 020 (ST-2). WGS allowed characterization of relapse with increased certainty and identified emergent within-strain single nucleotide variants (SNVs) with potential functional impact on diverse genes. Shared ribotypes among 14 patients with recurrent CDI suggested 10 possible patient-to-patient transmission events. However, WGS revealed greater diversity at the sub-ribotype level, excluding all but four transmission events. CONCLUSION: WGS exhibits several advantages over PCR-based ribotyping in terms of its ability to distinguish relapse from reinfection, to identify patient-to-patient transmission events, and to exact fine structure characterization of recurrent CDI epidemiology. This offers the potential for more focused infection prevention strategies to eliminate strain transmission among patients with recurrent CDI.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Clostridioides difficile/genetics , Clostridioides difficile/isolation & purification , Clostridium Infections/drug therapy , Clostridium Infections/transmission , Ribotyping , Adult , Aged , Aged, 80 and over , Clostridium Infections/epidemiology , Female , Genome , Humans , Ireland , Male , Middle Aged , Molecular Sequence Data , Polymerase Chain Reaction , Prospective Studies , Recurrence
8.
BJOG ; 121(7): 809-19; discussion 820, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24495335

ABSTRACT

OBJECTIVE: To determine risk of Down syndrome (DS) in multiple relative to singleton pregnancies, and compare prenatal diagnosis rates and pregnancy outcome. DESIGN: Population-based prevalence study based on EUROCAT congenital anomaly registries. SETTING: Eight European countries. POPULATION: 14.8 million births 1990-2009; 2.89% multiple births. METHODS: DS cases included livebirths, fetal deaths from 20 weeks, and terminations of pregnancy for fetal anomaly (TOPFA). Zygosity is inferred from like/unlike sex for birth denominators, and from concordance for DS cases. MAIN OUTCOME MEASURES: Relative risk (RR) of DS per fetus/baby from multiple versus singleton pregnancies and per pregnancy in monozygotic/dizygotic versus singleton pregnancies. Proportion of prenatally diagnosed and pregnancy outcome. STATISTICAL ANALYSIS: Poisson and logistic regression stratified for maternal age, country and time. RESULTS: Overall, the adjusted (adj) RR of DS for fetus/babies from multiple versus singleton pregnancies was 0.58 (95% CI 0.53-0.62), similar for all maternal ages except for mothers over 44, for whom it was considerably lower. In 8.7% of twin pairs affected by DS, both co-twins were diagnosed with the condition. The adjRR of DS for monozygotic versus singleton pregnancies was 0.34 (95% CI 0.25-0.44) and for dizygotic versus singleton pregnancies 1.34 (95% CI 1.23-1.46). DS fetuses from multiple births were less likely to be prenatally diagnosed than singletons (adjOR 0.62 [95% CI 0.50-0.78]) and following diagnosis less likely to be TOPFA (adjOR 0.40 [95% CI 0.27-0.59]). CONCLUSIONS: The risk of DS per fetus/baby is lower in multiple than singleton pregnancies. These estimates can be used for genetic counselling and prenatal screening.


Subject(s)
Down Syndrome/diagnosis , Down Syndrome/epidemiology , Pregnancy, Multiple , Prenatal Diagnosis , Adult , Europe/epidemiology , Female , Humans , Maternal Age , Middle Aged , Pregnancy , Pregnancy Outcome , Prevalence , Risk , Risk Assessment , Twins, Dizygotic , Twins, Monozygotic , Young Adult
9.
BJOG ; 120(6): 707-16, 2013 May.
Article in English | MEDLINE | ID: mdl-23384325

ABSTRACT

OBJECTIVE: To assess the public health consequences of the rise in multiple births with respect to congenital anomalies. DESIGN: Descriptive epidemiological analysis of data from population-based congenital anomaly registries. SETTING: Fourteen European countries. POPULATION: A total of 5.4 million births 1984-2007, of which 3% were multiple births. METHODS: Cases of congenital anomaly included live births, fetal deaths from 20 weeks of gestation and terminations of pregnancy for fetal anomaly. MAIN OUTCOME MEASURES: Prevalence rates per 10,000 births and relative risk of congenital anomaly in multiple versus singleton births (1984-2007); proportion prenatally diagnosed, proportion by pregnancy outcome (2000-07). Proportion of pairs where both co-twins were cases. RESULTS: Prevalence of congenital anomalies from multiple births increased from 5.9 (1984-87) to 10.7 per 10,000 births (2004-07). Relative risk of nonchromosomal anomaly in multiple births was 1.35 (95% CI 1.31-1.39), increasing over time, and of chromosomal anomalies was 0.72 (95% CI 0.65-0.80), decreasing over time. In 11.4% of affected twin pairs both babies had congenital anomalies (2000-07). The prenatal diagnosis rate was similar for multiple and singleton pregnancies. Cases from multiple pregnancies were less likely to be terminations of pregnancy for fetal anomaly, odds ratio 0.41 (95% CI 0.35-0.48) and more likely to be stillbirths and neonatal deaths. CONCLUSIONS: The increase in babies who are both from a multiple pregnancy and affected by a congenital anomaly has implications for prenatal and postnatal service provision. The contribution of assisted reproductive technologies to the increase in risk needs further research. The deficit of chromosomal anomalies among multiple births has relevance for prenatal risk counselling.


Subject(s)
Congenital Abnormalities/epidemiology , Fetal Death/epidemiology , Multiple Birth Offspring , Pregnancy Complications/epidemiology , Stillbirth/epidemiology , Europe/epidemiology , Female , Humans , Pregnancy , Pregnancy Outcome , Prenatal Diagnosis , Prevalence , Registries , Risk
10.
Mol Ecol Resour ; 11(3): 541-9, 2011 May.
Article in English | MEDLINE | ID: mdl-21481212

ABSTRACT

Genomic DNA sequences and other genomic resources are essential towards the elucidation of the genomic bases of adaptive divergence and reproductive isolation. Here, we describe the construction, characterization and screening of a nonarrayed BAC library for lake whitefish (Coregonus clupeaformis). We then show how the combined use of BAC library screening and next-generation sequencing can lead to efficient full-length assembly of candidate genes. The lake whitefish BAC library consists of 181,050 clones derived from a single heterozygous fish. The mean insert size is 92 Kb, representing 5.2 haploid genome equivalents. Ten BAC clones were isolated following a quantitative real-time PCR screening approach that targeted five previously identified candidate genes. Sequencing of these clones on a 454 GS FLX system yielded 178,000 reads with a mean length of 358 bp, for a total of 63.8 Mb. De novo assembly and annotation then allowed retrieval of contigs corresponding to each candidate gene, which also contained up- and/or downstream noncoding sequences. These results suggest that the lake whitefish BAC library combined with next-generation sequencing technologies will be key resources to achieve a better understanding of both adaptive divergence and reproductive isolation in lake whitefish species pairs as well as salmonid evolution in general.


Subject(s)
Evolution, Molecular , Gene Library , Genetic Speciation , Salmonidae/genetics , Adaptation, Biological , Animals , Chromosomes, Artificial, Bacterial , DNA/chemistry , DNA/genetics , Genetic Vectors , Molecular Sequence Data , Phylogeny , Sequence Analysis, DNA
11.
Toxicol Lett ; 201(2): 110-5, 2011 Mar 05.
Article in English | MEDLINE | ID: mdl-21172411

ABSTRACT

Rosiglitazone, a peroxisome proliferator-activated receptor γ (PPARγ) agonist of the thiazolidinedione class, is a major insulin-sensitizing drug widely used to treat type-2 diabetes. Rosiglitazone causes myocardial hypertrophy in rodents and increases the risk of cardiac events in man. To better characterize its cardiac effects, male Wistar rats were orally administered 0, 10 or 80 mg/kg/day rosiglitazone. Myocardial gene expression profiling, hematology, histopathology and clinical chemistry, including measurement of serum cardiac troponin (cTn) I concentration with the ultrasensitive assay, were evaluated after 6 and 24h and 7 and 14 days of dosing. Heart weight was increased 10% after 7 days and 16% after 14 days of dosing at 80 mg/kg/day in the absence of microscopic changes. At the transcriptomic level, the number of differentially expressed probes was small: it was most at 24h in rats given 80 mg/kg rosiglitazone with 356 differentially regulated probes (fold change >1.3 fold, p<0.05). Also, gene categories typically associated with myocardial damage were not over-represented. Most importantly, serum cTnI concentrations in 5/9 rats after 7 days of dosing at 80 mg/kg/day were above the upper limit of serum cTnI concentration. cTnI concentrations after 14 days of dosing were similar between rats given the vehicle and rosiglitazone at 80 mg/kg. This is the first study to detect increases of serum cTnI concentrations in rats administered rosiglitazone. In light of reported cardiac events in patients chronically dosed with PPARγ agonists, our results support serum cTnI concentrations as an early biomarker of cardiac liability.


Subject(s)
Heart/drug effects , Hypoglycemic Agents/toxicity , PPAR gamma/agonists , Thiazolidinediones/toxicity , Troponin I/blood , Animals , Gene Expression Profiling , Male , Myocardium/pathology , Organ Size/drug effects , Rats , Rats, Wistar , Rosiglitazone
12.
Plant Biol (Stuttg) ; 12(2): 364-76, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20398242

ABSTRACT

In this study, we compared interactions of two Melampsora foliar rust species with poplar, which resulted in either limited or abundant pathogen proliferation. In the pathosystem exhibiting limited pathogen growth, a defence response was observed after invasion of poplar leaf tissues by the biotroph, with late and clear production of reactive oxygen species (ROS) and other products. Characterisation of the histological, biochemical and transcriptional events occurring in both pathosystems showed striking similarity with components of plant defence reactions observed during qualitative resistance. Key components associated with development of an active defence response, such as up-regulation of pathogenesis-related (PR) genes, were observed during infection. Moreover, the time course and strength of gene induction appear to be critical determinants for the outcome of the tree-pathogen interaction. This work provides basic biochemical characterisation and expression data for the study of so-called partial resistance in the poplar-rust pathosystem, which is also applicable to other plant-pathogen interactions resulting in quantitative disease resistance.


Subject(s)
Basidiomycota/physiology , Host-Pathogen Interactions , Plant Diseases/immunology , Populus/microbiology , Gene Expression Regulation, Plant , Immunity, Innate , Plant Diseases/genetics , Plant Diseases/microbiology , Plant Leaves/immunology , Plant Leaves/microbiology , Populus/genetics , Populus/immunology , RNA, Plant/genetics , Reactive Oxygen Species/metabolism
15.
Br J Ophthalmol ; 92(1): 131-4, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18156379

ABSTRACT

BACKGROUND/AIMS: Glucocorticoids have an important role in the regulation of the immune system, and alterations in glucocorticoid signaling may have an impact on the pathophysiology of autoimmune and inflammatory disorders. Because polymorphisms of the glucocorticoid receptor (GR) gene, including the N363S, ER22/23EK, A3669G and BclI variants were found to influence glucocorticoid signalling, we examined whether these polymorphisms could be associated with the development or clinical manifestations of Graves ophthalmopathy (GO). METHODS: The carrier and allelic frequencies of the N363S, ER22/23EK, A3669G, and BclI polymorphisms of the GR were determined in 95 Hungarian outpatients with GO and 160 healthy controls. RESULTS: No significant changes were found in carrier frequencies of the four polymorphisms between GO patients and healthy controls. However, when GO patients were divided into two subgroups (American Thyroid Association Committee, ATA I-II vs ATA III or greater), the frequency of the polymorphic BclI allele was significantly higher in patients with ATA I-II compared with those with ATA III or more (p = 0.009). CONCLUSION: The significant association between the frequency of the polymorphic BclI allele and ATA stage distribution suggests that this polymorphism of the GR gene may affect clinical manifestations of GO, presumably due to an increased signaling of endogenous glucocorticoids.


Subject(s)
Graves Ophthalmopathy/genetics , Polymorphism, Genetic , Receptors, Glucocorticoid/genetics , Adult , Aged , Female , Gene Frequency , Graves Ophthalmopathy/pathology , Heterozygote , Humans , Male , Middle Aged , Severity of Illness Index
16.
Br J Haematol ; 132(6): 755-69, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16487177

ABSTRACT

Most acute myeloid leukaemia (AML) patients lack human leucocyte antigen-identical sibling donors for transplantation. Autotransplants and unrelated donor (URD) transplants are therapeutic options. To compare autologous versus URD transplantation for AML in first (CR1) or second complete remission (CR2), we studied the outcomes of 668 autotransplants were compared with 476 URD transplants reported to the Center for International Blood and Marrow Transplant Research. Proportional hazards regression adjusted for differences in prognostic variables. In multivariate analyses transplant-related mortality (TRM) was significantly higher and relapse lower with URD transplantation. Adjusted 3-year survival probabilities were: in CR1 57 (53-61)% with autotransplants and 44 (37-51)% URD (P = 0.002), in CR2 46 (39-53)% and 33 (28-38)% respectively (P = 0.006). Adjusted 3-year leukaemia-free survival (LFS) probabilities were: CR1 53 (48-57)% with autotransplants and 43 (36-50)% with URD (P = 0.021), CR2 39 (32-46)% and 33 (27-38)% respectively (P = 0.169). Both autologous and URD transplantation produced prolonged LFS. High TRM offsets the superior antileukaemia effect of URD transplantation. This retrospective, observational database study showed that autotransplantation, in general, offered higher 3-year survival for AML patients in CR1 and CR2. Cytogenetics, however, were known in only two-thirds of patients and treatment bias cannot be eliminated.


Subject(s)
Bone Marrow Transplantation/methods , Hematopoietic Stem Cell Transplantation/methods , Leukemia, Myeloid/surgery , Acute Disease , Adolescent , Adult , Child , Female , Histocompatibility Testing/methods , Humans , Leukemia, Myeloid/mortality , Male , Neoplasm Recurrence, Local , Retrospective Studies , Survival Analysis , Transplantation, Autologous/methods , Transplantation, Homologous/methods , Treatment Outcome
17.
AIDS Patient Care STDS ; 20(1): 48-56, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16426156

ABSTRACT

A high level of adherence to highly active antiretroviral therapy (HAART) is essential to minimize the risk of treatment failure and HIV disease progression. This cohort study evaluated the prevalence and predictors of long-term adherence with first-line HAART in a hospital-based unselected sample of HIV patients from central Italy, and examined the association between adherence and virological response or relapse. Between July 1996 and June 2004, 171 patients (67.3% males; mean age, 41.2 years) were followed for at least 24 weeks and up to 8 years. Adherence was measured by patient self-reports and confirmed using pharmacy records. The prevalence of high-level adherence (>or=90%) at 6 months was 88.3%; slightly less than 80% at 12 months. The incidence of adherence failure in the sample remained fairly stable until 24 months of follow-up, then it declined about 5% every 6 months. Cox analysis showed that compared to single/separated patients, homeless and married persons were, respectively, 1.95 times more likely and two times less likely to experience adherence failure (p < 0.05). The adjusted risk of adherence failure among patients who did not suffer drug-related toxicity was 0.57 (p < 0.05). Medication adherence was significantly associated with shorter time to virological response and longer time to relapse. Adherents were 1.69 times more likely to achieve viral suppression and nine times less likely to experience relapse than nonadherents (p < 0.01). Efforts at improving adherence should be prolonged for at least 24 months. A protective role of marriage for adherence failure is promising but requires confirmation in further research, that should also clarify the exact mechanisms determining the association.


Subject(s)
Antiretroviral Therapy, Highly Active , HIV Infections/drug therapy , HIV-1/drug effects , Hospitals , Patient Compliance , Adult , Cohort Studies , Female , HIV Infections/virology , HIV-1/physiology , Humans , Italy , Male , Middle Aged , Predictive Value of Tests , Prevalence , RNA, Viral/blood , Recurrence , Time Factors
18.
Biochem Biophys Res Commun ; 331(1): 261-6, 2005 May 27.
Article in English | MEDLINE | ID: mdl-15845387

ABSTRACT

Here we report the identification of a new insulin-like growth factor binding protein homologue, provisionally designated insulin-like growth factor binding related protein-4 (IGFBP-rP4). IGFBP-rP4 was found to be most closely related to IGFBP-7 with 52% amino acid homology and 43% amino acid identity, and shares a similar domain structure. Semi-quantitative RT-PCR expression analysis demonstrated a pattern of downregulation of this gene in multiple tumor samples including lung and colon cancer, compared to matched adjacent normal tissue. Western blotting revealed a protein of approximately 38kDa expressed in both the cell pellet and secreted into the supernatant of transiently transfected Cos-7 cells. Cos-7 supernatants containing IGFBP-RP4 protein were observed to suppress the growth of HeLa cells in culture compared to vector controls. IGFBP-RP4 directly transiently transfected into HeLa cells also further confirmed the growth suppressive properties of this protein. Together these data suggest that IGFBP-RP4 may be a novel putative tumor suppressor protein.


Subject(s)
Insulin-Like Growth Factor Binding Proteins/genetics , Insulin-Like Growth Factor Binding Proteins/physiology , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/physiology , Amino Acid Sequence , Animals , Base Sequence , COS Cells , Chlorocebus aethiops , Cloning, Molecular , HeLa Cells , Humans , Insulin-Like Growth Factor Binding Proteins/classification , Insulin-Like Growth Factor Binding Proteins/metabolism , Molecular Sequence Data , Phylogeny , Tumor Suppressor Proteins/metabolism
19.
Plant Cell ; 13(11): 2525-37, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11701886

ABSTRACT

The potato pathogenesis-related gene PR-10a is transcriptionally activated in response to pathogen infection or elicitor treatment. Characterization of the cis-acting elements of the PR-10a promoter revealed the presence of a silencing element between residues -52 and -27 that contributes to transcriptional regulation. In this study, we have isolated a silencing element binding factor (SEBF) from potato tuber nuclei that binds to the coding strand of the silencing element in a sequence-specific manner. The consensus binding site of SEBF, PyTGTCNC, is present in a number of PR genes and shows striking similarity to the auxin response element. Mutational analysis of the PR-10a promoter revealed an inverse correlation between the in vitro binding of SEBF and the expression of PR-10a. SEBF was purified to homogeneity from potato tubers, and sequencing of the N terminus of the protein led to the isolation of a cDNA clone. Sequence analysis revealed that SEBF is homologous with chloroplast RNA binding proteins that possess consensus sequence-type RNA binding domains characteristic of heterogeneous nuclear ribonucleoproteins (hnRNPs). Overexpression of SEBF in protoplasts repressed the activity of a PR-10a reporter construct in a silencing element-dependent manner, confirming the role of SEBF as a transcriptional repressor.


Subject(s)
Chloroplasts/metabolism , DNA, Single-Stranded/genetics , DNA-Binding Proteins/genetics , Gene Expression Regulation, Plant , Nuclear Proteins/genetics , Plant Proteins , Repressor Proteins/genetics , Solanum tuberosum/genetics , Amino Acid Sequence , Base Sequence , Cell Nucleus/metabolism , Cell Nucleus/physiology , Cloning, Molecular , DNA Primers , DNA-Binding Proteins/metabolism , Molecular Sequence Data , Plant Leaves/physiology , Polymerase Chain Reaction , Promoter Regions, Genetic , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , Recombinant Proteins/metabolism , Repressor Proteins/metabolism , Sequence Alignment , Transcription, Genetic
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