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1.
Front Microbiol ; 8: 238, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28261190

RESUMEN

The study of mycobiota remains relatively unexplored due to the lack of sufficient available reference strains and databases compared to those of bacterial microbiome studies. Deep sequencing of Internal Transcribed Spacer (ITS) regions is the de facto standard for fungal diversity analysis. However, results are often biased because of the wide variety of sequence lengths in the ITS regions and the complexity of high-throughput sequencing (HTS) technologies. In this study, a curated ITS database, ntF-ITS1, was constructed. This database can be utilized for the taxonomic assignment of fungal community members. We evaluated the efficacy of strategies for mycobiome analysis by using this database and characterizing a mock fungal community consisting of 26 species representing 15 genera using ITS1 sequencing with three HTS platforms: Illumina MiSeq (MiSeq), Ion Torrent Personal Genome Machine (IonPGM), and Pacific Biosciences (PacBio). Our evaluation demonstrated that PacBio's circular consensus sequencing with greater than 8 full-passes most accurately reconstructed the composition of the mock community. Using this strategy for deep-sequencing analysis of the gut mycobiota in healthy Japanese individuals revealed two major mycobiota types: a single-species type composed of Candida albicans or Saccharomyces cerevisiae and a multi-species type. In this study, we proposed the best possible processing strategies for the three sequencing platforms, of which, the PacBio platform allowed for the most accurate estimation of the fungal community. The database and methodology described here provide critical tools for the emerging field of mycobiome studies.

2.
Int J Mol Med ; 36(3): 712-24, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26165378

RESUMEN

Spontaneously hypertensive rats (SHRs) and stroke-prone SHRs (SHRSP) are frequently used as models not only of essential hypertension and stroke, but also of attention-deficit hyperactivity disorder (ADHD). Normotensive Wistar-Kyoto (WKY) rats are normally used as controls in these studies. In the present study, we aimed to identify the genes causing hypertension and stroke, as well as the genes involved in ADHD using these rats. We previously analyzed gene expression profiles in the adrenal glands and brain. Since the kidneys can directly influence the functions of the cardiovascular, endocrine and sympathetic nervous systems, gene expression profiles in the kidneys of the 3 rat strains were examined using genome-wide microarray technology when the rats were 3 and 6 weeks old, a period in which rats are considered to be in a pre-hypertensive state. Gene expression profiles were compared between the SHRs and WKY rats and also between the SHRSP and SHRs. A total of 232 unique genes showing more than a 4-fold increase or less than a 4-fold decrease in expression were isolated as SHR- and SHRSP-specific genes. Candidate genes were then selected using two different web tools: the 1st tool was the Database for Annotation, Visualization and Integrated Discovery (DAVID), which was used to search for significantly enriched genes and categorized them using Gene Ontology (GO) terms, and the 2nd was Ingenuity Pathway Analysis (IPA), which was used to search for interactions among SHR- and also SHRSP­specific genes. The analyses of SHR-specific genes using IPA revealed that B-cell CLL/lymphoma 6 (Bcl6) and SRY (sex determining region Y)-box 2 (Sox2) were possible candidate genes responsible for causing hypertension in SHRs. Similar analyses of SHRSP-specific genes revealed that angiotensinogen (Agt), angiotensin II receptor-associated protein (Agtrap) and apolipoprotein H (Apoh) were possible candidate genes responsible for triggering strokes. Since our results revealed that SHRSP-specific genes isolated from the kidneys of rats at 6 weeks of age, included 6 genes related to Huntington's disease, we discussed the genetic association between ADHD and Huntington's disease.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/genética , Hipertensión/genética , Riñón/metabolismo , Accidente Cerebrovascular/genética , Transcriptoma , Animales , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Ratas Endogámicas SHR , Ratas Endogámicas WKY
3.
BMC Genomics ; 15: 699, 2014 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-25142801

RESUMEN

BACKGROUND: The availability of diverse second- and third-generation sequencing technologies enables the rapid determination of the sequences of bacterial genomes. However, identifying the sequencing technology most suitable for producing a finished genome with multiple chromosomes remains a challenge. We evaluated the abilities of the following three second-generation sequencers: Roche 454 GS Junior (GS Jr), Life Technologies Ion PGM (Ion PGM), and Illumina MiSeq (MiSeq) and a third-generation sequencer, the Pacific Biosciences RS sequencer (PacBio), by sequencing and assembling the genome of Vibrio parahaemolyticus, which consists of a 5-Mb genome comprising two circular chromosomes. RESULTS: We sequenced the genome of V. parahaemolyticus with GS Jr, Ion PGM, MiSeq, and PacBio and performed de novo assembly with several genome assemblers. Although GS Jr generated the longest mean read length of 418 bp among the second-generation sequencers, the maximum contig length of the best assembly from GS Jr was 165 kbp, and the number of contigs was 309. Single runs of Ion PGM and MiSeq produced data of considerably greater sequencing coverage, 279× and 1,927×, respectively. The optimized result for Ion PGM contained 61 contigs assembled from reads of 77× coverage, and the longest contig was 895 kbp in size. Those for MiSeq were 34 contigs, 58× coverage, and 733 kbp, respectively. These results suggest that higher coverage depth is unnecessary for a better assembly result. We observed that multiple rRNA coding regions were fragmented in the assemblies from the second-generation sequencers, whereas PacBio generated two exceptionally long contigs of 3,288,561 and 1,875,537 bps, each of which was from a single chromosome, with 73× coverage and mean read length 3,119 bp, allowing us to determine the absolute positions of all rRNA operons. CONCLUSIONS: PacBio outperformed the other sequencers in terms of the length of contigs and reconstructed the greatest portion of the genome, achieving a genome assembly of "finished grade" because of its long reads. It showed the potential to assemble more complex genomes with multiple chromosomes containing more repetitive sequences.


Asunto(s)
Cromosomas Bacterianos/genética , Genómica/métodos , Análisis de Secuencia/métodos , Genoma Bacteriano/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Vibrio parahaemolyticus/genética
4.
DNA Res ; 21(4): 439-46, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24670267

RESUMEN

Plasmodium falciparum malaria imposes a serious public health concern throughout the tropics. Although genetic tools are principally important to fully investigate malaria parasites, currently available forward and reverse tools are fairly limited. It is expected that parasites with a high mutation rate can readily acquire novel phenotypes/traits; however, they remain an untapped tool for malaria biology. Here, we generated a mutator malaria parasite (hereinafter called a 'malaria mutator'), using site-directed mutagenesis and gene transfection techniques. A mutator Plasmodium berghei line with a defective proofreading 3' → 5' exonuclease activity in DNA polymerase δ (referred to as PbMut) and a control P. berghei line with wild-type DNA polymerase δ (referred to as PbCtl) were maintained by weekly passage in ddY mice for 122 weeks. High-throughput genome sequencing analysis revealed that two PbMut lines had 175-178 mutations and a 86- to 90-fold higher mutation rate than that of a PbCtl line. PbMut, PbCtl, and their parent strain, PbWT, showed similar course of infection. Interestingly, PbMut lost the ability to form gametocytes during serial passages. We believe that the malaria mutator system could provide a novel and useful tool to investigate malaria biology.


Asunto(s)
ADN Polimerasa III/genética , Tasa de Mutación , Plasmodium berghei/genética , Animales , ADN Polimerasa III/metabolismo , Femenino , Malaria/parasitología , Ratones , Plasmodium berghei/crecimiento & desarrollo , Plasmodium berghei/metabolismo , Diferenciación Sexual
5.
Int J Mol Med ; 33(4): 887-96, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24452243

RESUMEN

Spontaneously hypertensive rats (SHR) and stroke-prone SHR (SHRSP) are frequently used as rat models not only of essential hypertension and stroke, but also of attention-deficit hyperactivity disorder (ADHD). Normotensive Wistar-Kyoto rats (WKY) are used as the control rats in these cases. An increasing number of studies has demonstrated the critical role of the central nervous system in the development and maintenance of hypertension. In a previous study, we analyzed the gene expression profiles in the adrenal glands of SHR. Thus, in this study, we analyzed gene expression profiles in the brains of SHR in order to identify the genes responsible for causing hypertension and stroke, as well as those involved in ADHD. Using genome-wide microarray technology, we examined the gene expression profiles in the brains of 3 rat strains (SHR, SHRSP and WKY) when the rats were 3 and 6 weeks of age, a period in which the rats are considered to be in a pre-hypertensive state. Gene expression profiles in the brain were compared between SHR and WKY, and between SHRSP and SHR. A total of 179 genes showing a >4- or <-4-fold change in expression were isolated, and candidate genes were selected using two different web tools: the first tool was the Database for Annotation, Visualization and Integrated Discovery (DAVID), which was used to search for significantly enriched genes, and categorized them using Gene Ontology (GO) terms, and the second was the network explorer of Ingenuity Pathway Analysis (IPA), which was used to search for interaction networks among SHR- and SHRSP-specific genes. The IPA of SHR-specific genes revealed that prostaglandin E receptor 4 (Ptger4) is one of the candidate genes responsible for causing hypertension in SHR, and that albumin (Alb) and chymase 1 (Cma1) are also responsible for causing hypertension in SHR in the presence of angiotensinogen (Agt). Similar analyses of SHRSP-specific genes revealed that the angiotensin II receptor-associated gene (Agtrap) interacts with the FBJ osteosarcoma oncogene (Fos), and with the angiotensin II receptor type-1b (Agtr1b). As Agtrap and Agtr1b not only participate in the 'uptake of norepinephrine' and 'blood pressure', but also in the 'behavior' of SHRSP at 6 weeks of age, our data demonstrate a close association between hypertension and ADHD.


Asunto(s)
Encéfalo/metabolismo , Perfilación de la Expresión Génica , Hipertensión/genética , Accidente Cerebrovascular/genética , Animales , Epistasis Genética , Redes Reguladoras de Genes/genética , Estudios de Asociación Genética , Anotación de Secuencia Molecular , Análisis de Secuencia por Matrices de Oligonucleótidos , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Reproducibilidad de los Resultados
6.
Biologics ; 7: 233-41, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24235814

RESUMEN

BACKGROUND: There is increasing concern about the speed with which health care providers can administer prophylaxis and treatment in an influenza pandemic. Generally, it takes several months to manufacture an influenza vaccine by propagation of the virus in chicken eggs or cultured cells. Newer, faster protocols for the production of vaccines that induce broad-spectrum immunity are therefore highly desirable. We previously developed human monoclonal antibody B-1 that shows broadly neutralizing activity against influenza A virus H3N2. B-1 recognizes an epitope region that includes an antiparallel ß-sheet structure underneath the receptor binding site of influenza hemagglutinin (HA). In this study, the efficacy of a synthetic peptide vaccine derived from this epitope region against influenza A was evaluated. MATERIALS AND METHODS: Two peptides were synthesized, the upper and lower peptides. These peptides comprise amino acid residues 167-187 and 225-241, respectively, of the B-1 epitope region of HA, which is involved in forming the ß-sheet structure. Both peptides were then coupled to keyhole limpet hemocyanin, and the peptides, alone or in combination, were used to immunize rabbits. The resulting antibody responses were examined by enzyme-linked immunosorbent assay. The upper peptide, but not the lower peptide, elicited antibodies that were reactive to HA. Interestingly, the use of both peptides together could elicit antibodies with a higher reactivity to HA than either peptide alone. The antibodies were found to react to HA at the N-terminus of the upper peptide, which is exposed at the surface of trimeric HA on influenza virions. DISCUSSION: The higher production of HA-reactive antibodies following immunization with both peptides suggests that the upper peptide forms the effective epitope structure in the binding state, and the lower peptide enhances the production of HA antibodies. This study could be the first step towards the development of pandemic viral vaccines that can be produced within short time periods.

7.
Biochem Biophys Res Commun ; 440(3): 393-8, 2013 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-24070610

RESUMEN

The non-structural protein NS2B/NS3 serine-protease complex of the dengue virus (DENV) is required for the maturation of the viral polyprotein. Dissociation of the NS2B cofactor from NS3 diminishes the enzymatic activity of the complex. In this study, we identified a small molecule inhibitor that interferes with the interaction between NS2B and NS3 using structure-based screening and a cell-based viral replication assay. A library containing 661,417 small compounds derived from the Molecular Operating Environment lead-like database was docked to the NS2B/NS3 structural model. Thirty-nine compounds with high scores were tested in a secondary screening using a cell-based viral replication assay. SK-12 was found to inhibit replication of all DENV serotypes (EC50=0.74-4.92 µM). In silico studies predicted that SK-12 pre-occupies the NS2B-binding site of NS3. Steady-state kinetics using a fluorogenic short peptide substrate demonstrated that SK-12 is a noncompetitive inhibitor against the NS2B/NS3 protease. Inhibition to Japanese encephalitis virus by SK-12 was relatively weak (EC50=29.81 µM), and this lower sensitivity was due to difference in amino acid at position 27 of NS3. SK-12 is the promising small-molecule inhibitor that targets the interaction between NS2B and NS3.


Asunto(s)
Antivirales/farmacología , Dengue/tratamiento farmacológico , Naftoles/farmacología , Serina Proteasas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Sulfonamidas/farmacología , Proteínas no Estructurales Virales/química , Replicación Viral/efectos de los fármacos , Simulación por Computador , Dengue/enzimología , Humanos , Modelos Químicos , Conformación Proteica
8.
PLoS One ; 8(5): e64017, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23704970

RESUMEN

To rapidly and specifically identify highly virulent influenza virus strains, we prepared an azobenzene-tethered hairpin-type peptide nucleic acid, bisPNA-AZO, which has a complementary sequence against a highly conserved genomic RNA sequence within the ribonucleoprotein complex of the 2009 pandemic influenza A virus, H1N1 subtype. bisPNA-AZO recognizes the conserved virus genome sequence in a sequence-specific manner. Immobilization of bisPNA-AZO on a plate allowed capture of the target virus gene and the generation of a visual colour signal.


Asunto(s)
Compuestos Azo/metabolismo , Genes Virales/genética , Orthomyxoviridae/genética , Ácidos Nucleicos de Péptidos/metabolismo , Proteínas no Estructurales Virales/genética , Compuestos Azo/química , Secuencia de Bases , Secuencia Conservada/genética , Fluorescencia , Genoma Viral/genética , Proteínas Inmovilizadas/metabolismo , Ácidos Nucleicos de Péptidos/química , Unión Proteica , ARN Viral/genética
9.
RNA ; 19(6): 803-10, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23611983

RESUMEN

piRNA (PIWI-interacting RNA) is a germ cell-specific small RNA in which biogenesis PIWI (P-element wimpy testis) family proteins play crucial roles. MILI (mouse Piwi-like), one of the three mouse PIWI family members, is indispensable for piRNA production, DNA methylation of retrotransposons presumably through the piRNA, and spermatogenesis. The biogenesis of piRNA has been divided into primary and secondary processing pathways; in both of these MILI is involved in mice. To analyze the molecular function of MILI in piRNA biogenesis, we utilized germline stem (GS) cells, which are derived from testicular stem cells and possess a spermatogonial phenotype. We established MILI-null GS cell lines and their revertant, MILI-rescued GS cells, by introducing the Mili gene with Sendai virus vector. Comparison of wild-type, MILI-null, and MILI-rescued GS cells revealed that GS cells were quite useful for analyzing the molecular mechanisms of piRNA production, especially the primary processing pathway. We found that glycerol-3-phosphate acyltransferase 2 (GPAT2), a mitochondrial outer membrane protein for lysophosphatidic acid, bound to MILI using the cells and that gene knockdown of GPAT2 brought about impaired piRNA production in GS cells. GPAT2 is not only one of the MILI bound proteins but also a protein essential for primary piRNA biogenesis.


Asunto(s)
Glicerol-3-Fosfato O-Aciltransferasa/metabolismo , ARN Interferente Pequeño/metabolismo , Células Madre/metabolismo , Testículo/metabolismo , Animales , Animales Recién Nacidos , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Western Blotting , Proteínas de Ciclo Celular , Células Cultivadas , Técnicas de Silenciamiento del Gen , Vectores Genéticos/metabolismo , Glicerol-3-Fosfato O-Aciltransferasa/genética , Inmunoprecipitación , Lisofosfolípidos/metabolismo , Masculino , Ratones , Ratones Endogámicos DBA , MicroARNs/genética , MicroARNs/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , Membranas Mitocondriales/metabolismo , Unión Proteica , ARN Interferente Pequeño/genética , Ribonucleoproteínas Nucleares Pequeñas/genética , Ribonucleoproteínas Nucleares Pequeñas/metabolismo , Virus Sendai/genética , Virus Sendai/metabolismo , Células Madre/citología , Testículo/citología
10.
Int J Mol Med ; 31(5): 1057-65, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23525202

RESUMEN

Spontaneously hypertensive rats (SHR) and stroke-prone SHR (SHRSP) are frequently used as model rats not only in studies of essential hypertension and stroke, but also in studies of attention deficit hyperactivity disorder (ADHD). Normotensive Wistar-Kyoto rats (WKY) are normally used as controls in these studies. In this study, using these rats, we aimed to identify the genes causing hypertension and stroke, as well as the genes involved in ADHD. Since adrenal gland products can directly influence cardiovascular, endocrine and sympathetic nervous system functions, gene expression profiles in the adrenal glands of the 3 rat strains were examined using genome-wide microarray technology when the rats were 3 and 6 weeks of age, a period in which the rats are considered to be in a pre-hypertensive state. Gene expression profiles were compared between SHR and WKY and between SHRSP and SHR. A total of 353 genes showing more than a 4-fold increase or less than a 4-fold decrease in expression were isolated and candidate genes were selected as significantly enriched genes. SHR-specific genes isolated when the rats were 3 weeks of age contained 12 enriched genes related to transcriptional regulatory activity and those isolated when the rats were 6 weeks of age contained 6 enriched genes related to the regulation of blood pressure. SHRSP-specific genes isolated when the rats were 3 weeks of age contained 4 enriched genes related to the regulation of blood pressure and those isolated when the rats were 6 weeks of age contained 4 enriched genes related to the response to steroid hormone stimulus. Ingenuity pathway analysis of enriched SHR-specific genes revealed that 2 transcriptional regulators, cAMP responsive element modulator (Crem) and Fos-like antigen 1 (Fosl1), interact with blood pressure-regulating genes, such as neurotensin (Nts), apelin (Apln) and epoxide hydrolase 2, cytoplasmic (Ephx2). Similar analyses of SHRSP-specific genes revealed that angiotensinogen (Agt), one of the blood pressure-regulating genes, plays pivotal roles among SHRSP-specific genes. Moreover, genes associated with ADHD, such as low density lipoprotein receptor (Ldlr) and Crem, are discussed.


Asunto(s)
Predisposición Genética a la Enfermedad , Hipertensión/complicaciones , Hipertensión/genética , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/genética , Envejecimiento/genética , Envejecimiento/patología , Animales , Epistasis Genética , Redes Reguladoras de Genes/genética , Ratas , Ratas Endogámicas SHR
11.
Ther Innov Regul Sci ; 47(2): 235-241, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30227520

RESUMEN

This study aimed to determine the potentially severe chemical properties of drugs that can cause adverse drug reactions (ADRs) such as erythema multiforme (EM), Stevens-Johnson syndrome (SJS), and toxic epidermal necrolysis (TEN) by using a data mining method. The study data were extracted from the Adverse Event Reporting System database of the FDA. EM was considered a mild reaction, and SJS and TEN were considered severe reactions. In this study, a new concept termed the "risk of aggravation" (ROA) was defined as whether a certain drug is more likely to cause severe adverse reactions than mild ones. Partial least squares and logistic regression analysis were applied using binary response variable ROAs. These analyses correctly predicted 50 of the 72 drugs associated with SJS and/or TEN and 28 of the 38 drugs associated with EM using binary chemical descriptors that are the same as those using the metric chemical descriptors.

12.
J Mol Model ; 19(1): 465-75, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22949064

RESUMEN

Cyclophilin A has attracted attention recently as a new target of anti-human immunodeficiency virus type 1 (HIV-1) drugs. However, so far no drug against HIV-1 infection exhibiting this mechanism of action has been approved. To identify new potent candidates for inhibitors, we performed in silico screening of a commercial database of more than 1,300 drug-like compounds by using receptor-based docking studies. The candidates selected from docking studies were subsequently tested using biological assays to assess anti-HIV activities. As a result, two compounds were identified as the most active. Specifically, both exhibited anti-HIV activity against viral replication at a low concentration and relatively low cytotoxicity at the effective concentration inhibiting viral growth by 50%. Further modification of these molecules may lead to the elucidation of potent inhibitors of HIV-1.


Asunto(s)
Fármacos Anti-VIH/farmacología , Simulación por Computador , Ciclofilina A/metabolismo , Descubrimiento de Drogas , VIH-1/efectos de los fármacos , Fármacos Anti-VIH/química , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Evaluación Preclínica de Medicamentos , VIH-1/fisiología , Humanos , Ligandos , Simulación del Acoplamiento Molecular , Peso Molecular , Termodinámica , Replicación Viral/efectos de los fármacos
13.
Biol Open ; 1(4): 385-90, 2012 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-23213428

RESUMEN

Genetic reassortment plays a vital role in the evolution of the influenza virus and has historically been linked with the emergence of pandemic strains. Reassortment is believed to occur when a single host - typically swine - is simultaneously infected with multiple influenza strains. The reassorted viral strains with novel gene combinations tend to easily evade the immune system in other host species, satisfying the basic requirements of a virus with pandemic potential. Therefore, it is vital to continuously monitor the genetic content of circulating influenza strains and keep an eye out for new reassortants. We present a new approach to identify reassortants from large data sets of influenza whole genome nucleotide sequences and report the results of the first ever comprehensive search for reassortants of all published influenza A genomic data. 35 of the 52 well supported candidate reassortants we found are reported here for the first time while our analysis method offers new insight that enables us to draw a more detailed picture of the origin of some of the previously reported reassortants. A disproportionately high number (13/52) of the candidate reassortants found were the result of the introduction of novel hemagglutinin and/or neuraminidase genes into a previously circulating virus. The method described in this paper may contribute towards automating the task of routinely searching for reassortants among newly sequenced strains.

14.
Nat Genet ; 44(9): 1051-5, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22863735

RESUMEN

P. cynomolgi, a malaria-causing parasite of Asian Old World monkeys, is the sister taxon of P. vivax, the most prevalent malaria-causing species in humans outside of Africa. Because P. cynomolgi shares many phenotypic, biological and genetic characteristics with P. vivax, we generated draft genome sequences for three P. cynomolgi strains and performed genomic analysis comparing them with the P. vivax genome, as well as with the genome of a third previously sequenced simian parasite, Plasmodium knowlesi. Here, we show that genomes of the monkey malaria clade can be characterized by copy-number variants (CNVs) in multigene families involved in evasion of the human immune system and invasion of host erythrocytes. We identify genome-wide SNPs, microsatellites and CNVs in the P. cynomolgi genome, providing a map of genetic variation that can be used to map parasite traits and study parasite populations. The sequencing of the P. cynomolgi genome is a critical step in developing a model system for P. vivax research and in counteracting the neglect of P. vivax.


Asunto(s)
Genoma de Protozoos , Haplorrinos/parasitología , Enfermedades de los Monos/parasitología , Plasmodium cynomolgi/genética , Plasmodium vivax/genética , Animales , Secuencia de Bases , Análisis por Conglomerados , Genes Protozoarios , Genoma de Protozoos/genética , Malaria/genética , Malaria/parasitología , Modelos Genéticos , Datos de Secuencia Molecular , Enfermedades de los Monos/clasificación , Enfermedades de los Monos/genética , Filogenia , Plasmodium cynomolgi/clasificación , Plasmodium vivax/clasificación , Análisis de Secuencia de ADN
15.
J Gen Virol ; 93(Pt 10): 2215-2226, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22791605

RESUMEN

Highly pathogenic avian influenza virus H5N1 has spread across Eurasia and Africa, and outbreaks are now endemic in several countries, including Indonesia, Vietnam and Egypt. Continuous circulation of H5N1 virus in Egypt, from a single infected source, has led to significant genetic diversification with phylogenetically separable sublineages, providing an opportunity to study the impact of genetic evolution on viral phenotypic variation. In this study, we analysed the phylogeny of H5 haemagglutinin (HA) genes in influenza viruses isolated in Egypt from 2006 to 2011 and investigated the effect of conserved amino acid mutations in the HA genes in each of the sublineages on their antigenicity. The analysis showed that viruses in at least four sublineages still persisted in poultry in Egypt as of 2011. Using reverse genetics to generate HA-reassortment viruses with specific HA mutations, we found antigenic drift in the HA in two influenza virus sublineages, compared with the other currently co-circulating influenza virus sublineages in Egypt. Moreover, the two sublineages with significant antigenic drift were antigenically distinguishable. Our findings suggested that phylogenetically divergent H5N1 viruses, which were not antigenically cross-reactive, were co-circulating in Egypt, indicating that there was a problem in using a single influenza virus strain as seed virus to produce influenza virus vaccine in Egypt and providing data for designing more efficacious control strategies in H5N1-endemic areas.


Asunto(s)
Antígenos Virales/inmunología , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Subtipo H5N1 del Virus de la Influenza A/genética , Subtipo H5N1 del Virus de la Influenza A/inmunología , Gripe Aviar/virología , Secuencia de Aminoácidos , Animales , Anticuerpos/inmunología , Secuencia de Bases , Línea Celular , Embrión de Pollo , Pollos/genética , Pollos/inmunología , Pollos/virología , Reacciones Cruzadas/genética , Reacciones Cruzadas/inmunología , Brotes de Enfermedades , Perros , Egipto/epidemiología , Evolución Molecular , Glicosilación , Células HEK293 , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Humanos , Vacunas contra la Influenza/inmunología , Gripe Aviar/epidemiología , Gripe Aviar/genética , Gripe Aviar/inmunología , Datos de Secuencia Molecular , Mutación/genética , Mutación/inmunología , Filogenia , Prevalencia
16.
J Biol Chem ; 287(30): 25615-30, 2012 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-22654117

RESUMEN

A variety of proteins, including tenascin-C and osteopontin, have been identified as ligands for integrin α9ß1. However, their affinities for integrin α9ß1 are apparently much lower than those of other integrins (e.g. α3ß1, α5ß1, and α8ß1) for their specific ligands, leaving the possibility that physiological ligands for integrin α9ß1 still remain unidentified. In this study, we found that polydom (also named SVEP1) mediates cell adhesion in an integrin α9ß1-dependent manner and binds directly to recombinant integrin α9ß1 with an affinity that far exceeds those of the known ligands. Using a series of recombinant polydom proteins with N-terminal deletions, we mapped the integrin-binding site to the 21st complement control protein domain. Alanine-scanning mutagenesis revealed that the EDDMMEVPY sequence (amino acids 2636-2644) in the 21st complement control protein domain was involved in the binding to integrin α9ß1 and that Glu(2641) was the critical acidic residue for the integrin binding. The importance of this sequence was further confirmed by integrin binding inhibition assays using synthetic peptides. Immunohistochemical analyses of mouse embryonic tissues showed that polydom colocalized with integrin α9 in the stomach, intestine, and other organs. Furthermore, in situ integrin α9ß1 binding assays using frozen mouse tissues showed that polydom accounts for most, but not all, of the integrin α9ß1 ligands in tissues. Taken together, the present findings indicate that polydom is a hitherto unknown ligand for integrin α9ß1 that functions as a physiological ligand in vivo.


Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Integrinas/metabolismo , Proteínas/metabolismo , Secuencia de Aminoácidos , Animales , Proteínas de Unión al Calcio , Moléculas de Adhesión Celular/genética , Línea Celular Tumoral , Humanos , Integrinas/genética , Ligandos , Ratones , Mutagénesis , Especificidad de Órganos/fisiología , Proteínas/genética , Eliminación de Secuencia
17.
PLoS One ; 7(2): e30946, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22363521

RESUMEN

BACKGROUND: In April 2009, a novel swine-derived influenza A virus (H1N1pdm) emerged and rapidly spread around the world, including Japan. It has been suggested that the virus can bind to both 2,3- and 2,6-linked sialic acid receptors in infected mammals, in contrast to contemporary seasonal H1N1 viruses, which have a predilection for 2,6-linked sialic acid. METHODS/RESULTS: To elucidate the existence and transmissibility of α2,3 sialic acid-specific viruses in H1N1pdm, amino acid substitutions within viral hemagglutinin molecules were investigated, especially D187E, D222G, and Q223R, which are related to a shift from human to avian receptor specificity. Samples from individuals infected during the first and second waves of the outbreak in Japan were examined using a high-throughput sequencing approach. In May 2009, three specimens from mild cases showed D222G and/or Q223R substitutions in a minor subpopulation of viruses infecting these individuals. However, the substitutions almost disappeared in the samples from five mild cases in December 2010. The D187E substitution was not widespread in specimens, even in May 2009. CONCLUSIONS: These results suggest that α2,3 sialic acid-specific viruses, including G222 and R223, existed in humans as a minor population in the early phase of the pandemic, and that D222 and Q223 became more dominant through human-to-human transmission during the first and second waves of the epidemic. These results are consistent with the low substitution rates identified in seasonal H1N1 viruses in 2008.


Asunto(s)
Sustitución de Aminoácidos/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Subtipo H1N1 del Virus de la Influenza A/genética , Tasa de Mutación , Pandemias , Secuencia de Aminoácidos , Animales , Sitios de Unión , Línea Celular , Embrión de Pollo , Perros , Pruebas de Hemaglutinación , Glicoproteínas Hemaglutininas del Virus de la Influenza/química , Glicoproteínas Hemaglutininas del Virus de la Influenza/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Japón/epidemiología , Datos de Secuencia Molecular , Proteínas Mutantes/química , Nariz/microbiología , Óvulo/virología , Receptores Virales/metabolismo , Alineación de Secuencia , Análisis de Secuencia de Proteína , Pase Seriado , Manejo de Especímenes
18.
Environ Microbiol ; 14(2): 441-52, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22040222

RESUMEN

Viruses have been detected in the different stages of wastewater treatment plants (WWTPs) at concentrations of 10(8) -10(10) ml(-1) of virus-like particles (VLPs), 10-1000 times higher than in natural aquatic environments, suggesting that WWTPs can be considered as an important reservoir and source of viruses. This study revealed novel diversity and function with the DNA viral communities in the influent, activated sludge, anaerobic digester, and effluent of a domestic WWTP using metagenomics. WWTP was a very specific environment, with less than 5% of the > 936 000 metagenomic sequences obtained (∼70-119 Mbp per sample) similar to sequences present in other environmental viromes. Many viruses found in the WWTP were novel, resulting in only < 5-20% of the reads being phylogenetically or functionally assigned. DNA metabolism was observed as the most abundant function with DNA methylase detected at levels 4.2-fold higher than other published viromes, while carbohydrate and amino acids metabolisms were 3.7- and 4.2-fold less abundant respectively. These specific aspects of the WWTP community functions are likely due to high biomass concentration, turnover rate and microbial activity in WWTPs, and likely include mechanisms that help viruses increase their infectivity. Among ∼500 genotypes estimated in individual WWTP viromes, > 82% were shared. These data suggested that VLPs of most viral types could be present between 1 and 30 days in the process before they were discharged. Viruses in WWTP and the discharged ones can have potential impacts on the functioning of the wastewater treatment system and on the dynamics of microbial community in the surrounding aquatic environments respectively.


Asunto(s)
Virus ADN/clasificación , Metagenoma , Aguas del Alcantarillado/virología , Eliminación de Residuos Líquidos , Microbiología del Agua , Biomasa , Virus ADN/genética , Metagenómica , Clima Tropical
19.
PLoS Curr ; 3: RRN1285, 2011 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-22158699

RESUMEN

To gain insight into the possible origin of a new reassortant influenza A virus between pandemic (H1N1) 2009 and endemic swine viruses that has jumped the species barrier and caused a few infections among humans in Indiana and Pennsylvania recently, we analyzed all full genome sequences related to this virus and report its evolutionary history, but failed to determine how the virus had emerged simultaneously in two geographically distinct areas.

20.
AIDS Res Hum Retroviruses ; 26(2): 223-7, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20156104

RESUMEN

We report 25 env gp160 sequences from patients in three geographically distinct districts of Thailand, i.e., Lampang in the north, Trang in the south and Rayong in the east. One of these is a CRF01_AE/subtype B recombinant and the other 24 sequences are purely CRF01_AE. Very little interpopulation diversity was observed between the sequences from the three different geographic regions and from those previously reported by our laboratory from central Thailand. Potential N-linked glycosylation sites (PNLGs) were reasonably conserved among the 25 sequences: we found 15 highly conserved PNLGs on gp120 and 4 almost fully conserved PNLGs on gp41. Analysis of coreceptor tropism revealed that six of the isolates were dual tropic and the others were R5 tropic. We also examined a rare seven amino acid deletion found in one isolate at position 847-853 on gp41. These results may enhance our understanding of HIV-1 currently circulating in Thailand.


Asunto(s)
Proteínas gp160 de Envoltorio del VIH/genética , Infecciones por VIH/virología , VIH-1/genética , Análisis por Conglomerados , Secuencia Conservada , Genotipo , Geografía , VIH-1/aislamiento & purificación , Humanos , Epidemiología Molecular , Datos de Secuencia Molecular , Filogenia , Polimorfismo Genético , Receptores del VIH/análisis , Análisis de Secuencia de ADN , Tailandia
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