RESUMO
Human papillomavirus type 16 (HPV16) is the most common cause of cervical cancer, but most infections are transient with lesions not progressing to cancer. There is a lack of specific biomarkers for early cancer risk stratification. This study aimed to explore the intrahost HPV16 genomic variation in longitudinal samples from HPV16-infected women with different cervical lesion severity (normal, low-grade, and high-grade). The TaME-seq deep sequencing protocol was used to generate whole genome HPV16 sequences of 102 samples collected over time from 40 individuals. Single nucleotide variants (SNVs) and intrahost SNVs (iSNVs) were identified in the viral genomes. A majority of individuals had a unique set of SNVs and these SNVs were stable over time. Overall, the number of iSNVs and APOBEC3-induced iSNVs were significantly lower in high-grade relative to normal and low-grade samples. A significant increase in the number of APOBEC3-induced iSNVs over time was observed for normal samples when compared to high-grade. Our results indicates that the lower incidence of iSNVs and APOBEC3-induced iSNVs in high-grade lesions may have implications for novel biomarkers discoveries, potentially aiding early stratification of HPV-induced cervical precancerous lesions.
Assuntos
Variação Genética , Genoma Viral , Papillomavirus Humano 16 , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Infecções por Papillomavirus/virologia , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/isolamento & purificação , Estudos Longitudinais , Neoplasias do Colo do Útero/virologia , Neoplasias do Colo do Útero/patologia , Adulto , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
DNA processing chain A (DprA) is a DNA-binding protein that is ubiquitous in bacteria and expressed in some archaea. DprA is active in many bacterial species that are competent for transformation of DNA, but its role in Neisseriameningitidis (Nm) is not well characterized. An Nm mutant lacking DprA was constructed, and the phenotypes of the wild-type and ΔdprA mutant were compared. The salient feature of the phenotype of dprA null cells is the total lack of competence for genetic transformation shown by all of the donor DNA substrates tested in this study. Here, Nm wild-type and dprA null cells appeared to be equally resistant to genotoxic stress. The gene encoding DprANm was cloned and overexpressed, and the biological activities of DprANm were further investigated. DprANm binds ssDNA more strongly than dsDNA, but lacks DNA uptake sequence-specific DNA binding. DprANm dimerization and interaction with the C-terminal part of the single-stranded binding protein SSBNmwere demonstrated. dprA is co-expressed with smg, a downstream gene of unknown function, and the gene encoding topoisomerase 1, topA.
Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Membrana/metabolismo , Neisseria meningitidis/metabolismo , Transformação Bacteriana , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/genética , Neisseria meningitidis/química , Neisseria meningitidis/genética , Alinhamento de SequênciaRESUMO
Although anogenital cancers have been on a gradual rise in developing countries in the past few decades, they have been understudied. The objective was to investigate genotypic diversity of anogenital HPV amongst women reporting for routine cervical cancer screening in Harare in Zimbabwe. A cross-sectional study that enrolled 144 women ≥18 years from a cervical cancer-screening clinic was performed. Each woman provided a self-collected cervico-vaginal swab (VS) and a clinician-collected anal swab (CCAS). HIV testing was offered and cervical cytology was performed. Both VS and CCAS samples were HPV genotyped, using amplicon sequencing of the L1 gene region with Illumina technology. Mean age of the women was 39.9 (range 18-83 years, SD ± 11.0). HPV prevalence was 72% (104/144) in VS and 48% (69/144) in CCAS. The most common genotypes detected in both VS and CCAS were HPV18, HPV52, and HPV16. Sixty two percent of the subjects had multiple genotypic HPV infections. The odds of being HPV-positive among HIV-infected women were higher than in HIV-negative women in both the vagina and the anus (CCAS OR = 4.8; CI 2.4-9.8, P < 0.001) and (VS OR = 2.9; CI 1.3-6.4, P = 0.005). High HPV prevalence and diverse genotypes were detected in both the vagina and anus. Anal oncogenic HPV infection was common. HPV 52 was one of the most common oncogenic genotypes in both the vagina and anus. HIV co-infection played a significant role in the prevalence of HPV. These data have implications for design of primary and secondary programs for prevention of anogenital cancer in Zimbabwe.
