ViralORFeome: an integrated database to generate a versatile collection of viral ORFs.

Large collections of protein-encoding open reading frames (ORFs) established in a versatile recombination-based cloning system have been instrumental to study protein functions in high-throughput assays. Such 'ORFeome' resources have been developed for several organisms but in virology, plasmid collections covering a significant fraction of the virosphere are still needed. In this perspective, we present ViralORFeome 1.0 (http://www.viralorfeome.com), an open-access database and management system that provides an integrated set of bioinformatic tools to clone viral ORFs in the Gateway(R) system. ViralORFeome provides a convenient interface to navigate through virus genome sequences, to design ORF-specific cloning primers, to validate the sequence of generated constructs and to browse established collections of virus ORFs. Most importantly, ViralORFeome has been designed to manage all possible variants or mutants of a given ORF so that the cloning procedure can be applied to any emerging virus strain. A subset of plasmid constructs generated with ViralORFeome platform has been tested with success for heterologous protein expression in different expression systems at proteome scale. ViralORFeome should provide our community with a framework to establish a large collection of virus ORF clones, an instrumental resource to determine functions, activities and binding partners of viral proteins.

Mutation and abnormal expression of the p53 gene in the viral skin carcinogenesis of epidermodysplasia verruciformis.

Patients suffering from epidermodysplasia verruciformis are prone to nonmelanoma skin cancers, due to an inherited abnormal susceptibility to the oncogenic human papillomavirus type 5. Genotoxic sunlight ultraviolet B radiations are likely to be a cofactor. Lesions of two human-papillomavirus-type-5-infected epidermodysplasia verruciformis patients collected during an 8 y period were retrospectively studied for p53 mutations in exons 5 through 8 by a polymerase chain reaction single-strand conformation polymorphism technique and/or by DNA sequencing of amplified exons. Mutations were detected in 11 of 26 (42.3%) specimens, including five (62.5%) squamous cell carcinomas, three (33.3%) Bowen's carcinomas in situ, two (40%) actinic keratoses, and one (33%) benign lesion. The nine mutations characterized by sequencing were shown to be missense and to affect mutational hotspots in human cancers. Five were C-->T transitions at dicytidine sites considered as ultraviolet signature mutations. Two were transversions (C-->G and C-->A) at dicytidine sites and two were C-->T transitions at nondipyrimidine sites. A marked p53 immunoreactivity was disclosed in 72.7% of 11 invasive carcinomas, 55.6% of nine carcinomas in situ, 37.5% of eight actinic keratoses, and one of three benign lesions. This includes 81.8% of 11 specimens with a p53 mutation but also 50% of 14 specimens with no mutation detected. A dysfunction of the p53 gene is thus likely to play a part in epidermodysplasia verruciformis carcinogenesis, either due to ultraviolet-B-induced p53 mutations, as in nonmelanoma skin cancers in the general population, or involving other mutagens or mechanisms. The part played by human papillomavirus type 5 proteins expressed in epidermodysplasia verruciformis keratinocytes remains to be determined.

Human papillomavirus testing in women with mild cytologic atypia.

OBJECTIVE: To evaluate the efficiency of human papillomavirus (HPV) testing by Hybrid Capture II (Digene Diagnostics Inc., Silver Spring, MD) with regard to detecting biopsy-confirmed cervical intraepithelial neoplasia (CIN) or high-grade CIN in women with mild atypia, compared with the efficiencies of polymerase chain reaction (PCR), Southern blot hybridization, and cytology. METHODS: We prospectively studied 378 women with atypical squamous cells of undetermined significance (ASCUS) (n = 111) or low-grade squamous intraepithelial lesions (SILs) (n = 267) demonstrated by referral cytology. We did repeat cytology, sampling for detection of HPV DNA by Hybrid Capture II, PCR, and Southern blot hybridization, and colposcopic evaluation with cervical biopsies. RESULTS: All participants underwent the Hybrid Capture II test and 320 underwent the three HPV tests. Sensitivities of Hybrid Capture II for detecting CIN and high-grade CIN (0.81 and 0.86, respectively) were similar to those of cytology (0.83 and 0.82, respectively) and PCR (0.77 and 0.95, respectively), and higher than those of Southern blot hybridization (0.48 and 0.45, respectively). Compared with cytology, combined triage with Hybrid Capture II improved sensitivities for detecting CIN (0.94 versus 0.83, P <.001) and high-grade CIN (0.96 versus 0.85), though the latter difference was not significant (P =.17). In women with ASCUS, sensitivities of combined triage and cytology for detecting CIN were 0.94 and 0.71, respectively (P =.01), and sensitivities of the two methods for detecting high-grade CIN were 0.92 and 0.66, respectively (P =.13). The increase in sensitivity was lower among women with low-grade SILs; for these women, cytology had high sensitivity (0.86 for CIN and 1.00 for high-grade CIN). The specificity of combined triage was significantly lower than that of cytology in both groups. CONCLUSION: Compared with repeat cytology, combined triage with HPV testing markedly improves sensitivity for detecting CIN in women with ASCUS, but at the expense of specificity.

A cottontail rabbit papillomavirus strain (CRPVb) with strikingly divergent E6 and E7 oncoproteins: An insight in the evolution of papillomaviruses.

We previously observed that warts induced by an isolate of cottontail rabbit papillomavirus (CRPV) showed incomplete instead of systemic regression in some domestic rabbits. We report that the viral isolate contained, as a major component, a CRPV strain (CRPVb) showing an unexpectedly high divergence in the E6 and E7 open reading frames (ORFs), compared to the prototype CRPVa present in the isolate as a minor component. The E6 and E7 oncoproteins of CRPVa and -b disclosed only 87.5% identical amino acids and differed in size by three and two amino acids, respectively. This divergence involved (i) a great number (4.4%) of nucleotide substitutions and a high rate (83.3%) of nonsynonymous mutations; (ii) mutations changing the E6 and E7 stop codons; and (iii) in-frame sequence insertions in the E6 ORF (18 nucleotides) and downstream of the mutated E7 stop codon (6 nucleotides), both likely to result from a duplication of adjacent sequences. These extensive differences could account for distinct biological and antigenic properties. Strikingly, only four (0.8%) amino acids of the L1 major capsid protein were variable. Thus, it seems likely that sequence duplications and mutations affecting stop codons exert a strong selection pressure on the fixation of nonsynonymous mutations and that phylogenetic calculations based only on point mutations may misevaluate the time scale of the evolution of papillomaviruses.

Multiple pigmented cutaneous papules associated with a novel canine papillomavirus in an immunosuppressed dog.

Cutaneous papillomavirus infection was diagnosed in a 6-year-old female Boxer dog that was under long-term corticosteroid therapy for atopic dermatitis. Multiple black, rounded papules were present on the ventral skin. Spontaneous regression occurred within 3 weeks after cessation of corticosteroids. Histologically, the lesions consisted of well-demarcated cup-shaped foci of epidermal endophytic hyperplasia with marked parakeratosis. In the upper stratum spinosum and in the stratum granulosum, solitary or small collections of enlarged keratinocytes were observed with basophilic intranuclear inclusion bodies and a single eosinophilic fibrillar cytoplasmic inclusion. Ultrastructurally, viruslike particles (40-45 nm in diameter) were observed within the nucleus, free or aggregated in crystalline arrays. Undulating fibrillar material, thought to be a modified keratin protein, was observed in the cytoplasmic inclusion. Immunohistochemistry, restriction enzyme analysis, and molecular hybridization experiments indicated that these distinctive clinical, histologic, and cytologic features were associated with a novel canine papillomavirus.

A novel genital human papillomavirus (HPV), HPV type 74, found in immunosuppressed patients.

The genome of a novel human papillomavirus (HPV) type, HPV74, was cloned from an iatrogenically immunosuppressed woman with persisting low-grade vaginal intraepithelial neoplasia. HPV74 was found to be phylogenetically related to the low-risk HPV types 6, 11, 44, and 55. HPV74 or a variant of this type was found in specimens from three additional immunosuppressed women but not in about 3,000 anogenital specimens from immunocompetent patients.

[Action of small peptides, fragments of ACTH on the incorporation of P32 in brain proteins in vitro]. / Action de petits peptides, fragments d'ACTH, sur l'incorporation de P32 dans les protéines cérébrales in vitro.

Some small peptides, ACTH sequences, are able to modify the 32P incorporation in brain proteins in vitro. The possibility that these peptides play a role in the regulation mechanism of some brain functions through differentiated protein-kinases could be considered.