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1.
Virol J ; 21(1): 186, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39135075

RESUMEN

BACKGROUND: The global outbreak of COVID-19 caused by the SARS-CoV-2 has led to millions of deaths. This unanticipated emergency has prompted virologists across the globe to delve deeper into the intricate dynamicity of the host-virus interface with an aim to identify antiviral targets and elucidate host and viral determinants of severe disease. AIM: The present study was undertaken to analyse the role of histone deacetylase 6 (HDAC6) in regulating SARS-CoV-2 infection. RESULTS: Gradual increase in HDAC6 expression was observed in different SARS-CoV-2-permissive cell lines following SARS-CoV-2 infection. The SARS-CoV-2 nucleocapsid protein (N protein) was identified as the primary viral factor responsible for upregulating HDAC6 expression. Downregulation of HDAC6 using shRNA or a specific inhibitor tubacin resulted in reduced viral replication suggesting proviral role of its deacetylase activity. Further investigations uncovered the interaction of HDAC6 with stress granule protein G3BP1 and N protein during infection. HDAC6-mediated deacetylation of SARS-CoV-2 N protein was found to be crucial for its association with G3BP1. CONCLUSION: This study provides valuable insights into the molecular mechanisms underlying the disruption of cytoplasmic stress granules during SARS-CoV-2 infection and highlights the significance of HDAC6 in the process.


Asunto(s)
COVID-19 , Proteínas de la Nucleocápside de Coronavirus , Histona Desacetilasa 6 , SARS-CoV-2 , Replicación Viral , Histona Desacetilasa 6/metabolismo , Histona Desacetilasa 6/genética , Humanos , SARS-CoV-2/fisiología , Proteínas de la Nucleocápside de Coronavirus/metabolismo , Proteínas de la Nucleocápside de Coronavirus/genética , COVID-19/virología , COVID-19/metabolismo , Proteínas con Motivos de Reconocimiento de ARN/metabolismo , Acetilación , Línea Celular , Chlorocebus aethiops , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Células Vero , Animales , Interacciones Huésped-Patógeno , Proteínas de Unión a Poli-ADP-Ribosa , ADN Helicasas , ARN Helicasas
2.
Arch Virol ; 166(11): 2989-2998, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34383167

RESUMEN

Noroviruses are significant etiological agents of acute gastroenteritis (AGE) across all age groups, especially in children under 5 years of age. Although the prevalence of norovirus infection is known to have increased in various countries, in India there are few reports pertaining to the norovirus disease burden. We investigated the epidemiology and molecular characteristics of noroviruses in children seeking health care at two hospitals in Kolkata, Eastern India. Faecal specimens were collected between January 2018 and December 2019 from 2812 children under 5 years of age with acute gastroenteritis. Noroviruses were detected in 6.04% (170/2812) of the samples, and 12.9% (22/170) of these were cases of coinfection with rotavirus. Among children (≤5 years), a higher infection rate (8.2%, n = 94/1152) was observed in the 6 to 12 month age group. GII.4 Sydney 2012 was the dominant norovirus capsid genotype (n = 75/90, 83.3%), followed by GII.3 (n = 10/90, 11.1%). Other capsid types GII.13 (n = 4/90, 4.4%) and GII.17 (n = 1/90; 1.1%) were also detected at low frequency. Phylogenetic analysis showed that the GII.P16 polymerase of strains in this region clustered with those of the phylogenetically distinct monophyletic clade of GII.P16 strains, whose members have been circulating worldwide since 2014. Inter-genotypic norovirus recombinants such as GII.P16-GII.3 (n = 10) and GII.P16-GII.13 (n = 4) were also observed among the circulating strains. In comparison to previous studies from eastern India, the present study shows a higher detection rate of norovirus infection in the paediatric population suffering from acute gastroenteritis. Continuous surveillance is required for predicting the emergence of novel genotypes and recombinant strains and for future vaccine development.


Asunto(s)
Infecciones por Caliciviridae/virología , Gastroenteritis/virología , Norovirus/genética , Infecciones por Caliciviridae/epidemiología , Cápside , Niño , Preescolar , Epítopos/genética , Femenino , Gastroenteritis/epidemiología , Variación Genética , Genotipo , Humanos , India/epidemiología , Lactante , Masculino , Filogenia , Prevalencia , Proteínas Virales/genética
3.
Arch Virol ; 163(3): 745-750, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29248967

RESUMEN

In hospital-based diarrhoeal disease surveillance at Infectious Diseases & Beliaghata-General Hospital (May-2012 to April-2013), Kolkata, India, stool samples were collected from patients < 5 years (n = 830) and > 5 years of age (n = 728) hospitalized with diarrhea. Group-A rotavirus (GARV) was identified by ELISA followed by multiplex RT-PCR. In children < 5 years of age, 53.4% of the samples were positive for GARV. In patients > 5 years to 90 years old, only 6.04% (n = 44) tested positive for GARV. G2P[4] strains (n = 16 [36.36%]) were the most prevalent, followed by G9P[4] strains (n = 13 [29.54%]), while P[4]-(n = 30 [68.18%]) was most prevalent among the P genotypes. The GARV strains G2, G9 and P[4] detected in adults clustered together in the phylogenetic tree with the GARV strains identified in children (< 5 years) during the same period. Rotavirus positivity was high among female patients (75%), suggesting that caregivers (mother/grandmother/older-siblings) may get infected through young children or may act as carriers for transmission.


Asunto(s)
Diarrea/epidemiología , Genotipo , Filogenia , Infecciones por Rotavirus/epidemiología , Rotavirus/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cuidadores/educación , Niño , Preescolar , Diarrea/diagnóstico , Diarrea/virología , Heces/virología , Femenino , Hospitales , Humanos , India/epidemiología , Lactante , Masculino , Persona de Mediana Edad , Prevalencia , Rotavirus/clasificación , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/diagnóstico , Infecciones por Rotavirus/virología
4.
J Med Virol ; 89(4): 606-614, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27584661

RESUMEN

Human enteric adenovirus (HAdV) belonging to species F is one of the most common pathogens responsible for infantile gastroenteritis worldwide. This study was initiated to estimate prevalence and types of HAdV among children below 5 years of age seeking health care facility for treatment of diarrhea in Kolkata, Eastern India. A total of 1,562 stool specimens were tested during 2013-2014 and among them, 185 (11.8%) were positive for enteric HAdV. Maximum number of positive cases were observed among children between 6 and 12 months of age (13.9%). HAdV infection occurred at a low frequency throughout the year, with an increased incidence in the month of March-July in both the years. Among HAdV positive samples (n = 185), 44.8% showed coinfection with rotavirus. Genotyping based on hypervariable region of hexon and partial shaft region of fiber genes, revealed prevalence of HAdV-40 over HAdV-41 genotype during this study period. Nucleotide sequence analysis of HAdV-40 strains exhibited more than 99% similarity among themselves and 98.5% with the prototype strain Dugan. Sequence analysis of six hypervariable regions (HVRs) of hexon genes from all the HAdV-41 strains revealed co-circulation of both genome type cluster 1(GTC1) and GTC2. The presence of both types of GTCs reflects accumulation of amino acid (aa) mutations in HVR of hexon gene. A recombination event was evident in a subset of HAdV-41 strains where hexon gene belonged to GTC1 whereas, fiber gene clustered with GTC2. Sequence analysis of fiber gene shaft region of HAdV-41 strains revealed 15 aa deletion from the 15th repeat motif. J. Med. Virol. 89:606-614, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Infecciones por Adenovirus Humanos/virología , Adenovirus Humanos/clasificación , Adenovirus Humanos/genética , Gastroenteritis/virología , Genotipo , Infecciones por Adenovirus Humanos/epidemiología , Adenovirus Humanos/aislamiento & purificación , Adolescente , Adulto , Proteínas de la Cápside/genética , Niño , Preescolar , Análisis por Conglomerados , Heces/virología , Femenino , Gastroenteritis/epidemiología , Humanos , India/epidemiología , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Prevalencia , Análisis de Secuencia de ADN , Homología de Secuencia , Adulto Joven
5.
J Med Virol ; 85(8): 1459-65, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23765782

RESUMEN

In developing countries, viruses causing respiratory disease are a major concern of public health. During January 2010-December 2011, 2,737 patients with acute respiratory infection from the outpatient departments as well as patients admitted to hospitals were screened for different respiratory viruses. Nasal and or throat swabs were collected and transported to the laboratory where initial screening of influenza A and influenza B viruses was performed. The samples were tested further for influenza C virus, parainfluenza viruses 1-4, human rhinovirus, metapneumovirus and respiratory syncytial virus by conventional RT- PCR. The study revealed that the majority of the patients were under 5 years of age; both due to their higher susceptibility to respiratory infections and presentation to hospitals. Out of 2,737 patients enrolled in this study, 59% were found positive for one or more respiratory viruses. Influenza B infection was detected in 12% of patients followed by influenza A (11.7%), respiratory syncytial virus (7.1%), parainfluenza virus-2 (6%), metapneumovirus (3%), parainfluenza virus-3 (1%), parainfluenza virus-4 (0.6%), parainfluenza virus-1 (0.3%), influenza C (0.2%) and human rhinovirus (0.2%). Distinct seasonal infection was observed only for influenza A and influenza B viruses.


Asunto(s)
Virus ARN/clasificación , Virus ARN/aislamiento & purificación , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/virología , Virosis/epidemiología , Virosis/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Países en Desarrollo , Femenino , Humanos , India/epidemiología , Lactante , Masculino , Persona de Mediana Edad , Mucosa Nasal/virología , Faringe/virología , Prevalencia , ARN Viral/genética , ARN Viral/aislamiento & purificación , Infecciones del Sistema Respiratorio/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Virosis/patología , Adulto Joven
6.
Arch Virol ; 156(2): 207-17, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20981560

RESUMEN

During the peak outbreak (July-September 2009), a total 1886 patients were screened in eastern India, of which 139 (7.37%) and 52 (2.76%) were positive for pH1N1 and seasonal H1N1, respectively. Full-length HA1, NA, NS1 and PB1-F2 genes of representative strains were sequenced. Phylogenetic analysis of deduced amino acid sequences of pH1N1 strains revealed HA1 and NS1 to be of North American swine lineage, and the NA gene of Eurasian swine lineage. Consistent with previous reports, the PB1-F2 gene of pH1N1 strains was unique due to a mutation resulting in a truncated protein of 11 aa. The HA, NA and NS1 genes of H1N1/2009 strains clustered with H1N1 strains of 2000-2009, whereas a subset of strains contained a pH1N1-like truncated PB1-F2. The truncated PB1-F2 may confer the advantage of lower pathogenicity but higher replication and infectivity to the human H1N1 strains. This is the first report of seasonal H1N1/2009 strains with a pH1N1/2009-like gene segment.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/genética , Gripe Humana/epidemiología , Gripe Humana/virología , Pandemias , Secuencia de Aminoácidos , Genes Virales , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Humanos , India/epidemiología , Subtipo H1N1 del Virus de la Influenza A/clasificación , Subtipo H1N1 del Virus de la Influenza A/patogenicidad , Epidemiología Molecular , Datos de Secuencia Molecular , Mutación , Neuraminidasa/genética , Filogenia , Estaciones del Año , Homología de Secuencia de Aminoácido , Proteínas no Estructurales Virales/genética , Proteínas Virales/genética
7.
Vaccine ; 32 Suppl 1: A20-8, 2014 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-25091674

RESUMEN

INTRODUCTION: India accounts for an estimated 457,000-884,000 hospitalizations and 2 million outpatient visits for diarrhea. In spite of the huge burden of rotavirus (RV) disease, RV vaccines have not been introduced in national immunization programme of India. Therefore, continuous surveillance for prevalence and monitoring of the circulating genotypes is needed to assess the disease burden prior to introduction of vaccines in this region. METHODS: During January 2011 through December 2013, 830 and 1000 stool samples were collected from hospitalized and out-patient department (OPD) patients, respectively, in two hospitals in Kolkata, Eastern India. After primary screening, the G-P typing was done by multiplex semi-nested PCR using type specific primers followed by sequencing. Phylogenetic analysis for the VP7 gene of 25 representative strains was done. RESULTS: Among hospitalized and OPD patients, 53.4% and 47.5% cases were positive for rotaviruses, respectively. Unlike previous studies where G1 was predominant, in hospitalized cases G9 rotavirus strains were most prevalent (40%), followed by G2 (39.6%) whereas G1 and G12 occurred at 16.4% and 5.6% frequency. In OPD cases, the most prevalent strain was G2 (40.3%), followed by G1, G9 and G12 at 25.5%, 22.8%, 9.3%, respectively. Phylogenetically the G1, G2 and G9 strains from Kolkata did not cluster with corresponding genotypes of Rotarix, RotaTeq and Rotavac (116E) vaccine strains. CONCLUSION: The study highlights the high prevalence of RV in children with gastroenteritis in Kolkata. The circulating genotypes have changed over the time with predominance of G9 and G2 strains during 2011-2013. The current G2, G9 and G1 Kolkata strains shared low amino acid homologies with current vaccine strains. Although there is substantial evidence for cross protection of vaccines against a variety of strains, still the strain variation should be monitored post vaccine introduction to determine if it has any impact on vaccine effectiveness.


Asunto(s)
Gastroenteritis/epidemiología , Filogenia , Infecciones por Rotavirus/epidemiología , Rotavirus/genética , Antígenos Virales/genética , Proteínas de la Cápside/genética , Preescolar , Diarrea/epidemiología , Diarrea/virología , Gastroenteritis/virología , Genotipo , Hospitalización , Humanos , India/epidemiología , Lactante , Epidemiología Molecular , Infecciones por Rotavirus/virología
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