Philippe Clertant

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Nucleotide sequencing has revealed a common genetic organization for three papillomaviruses: BPV-1 (bovine papillomavirus type 1), HPV-1 (human papillomavirus type 1a) and HPV-6 (human papillomavirus type 6b). Several open reading frames, corresponding to as yet uncharacterized proteins, were observed in these genomes in the region that is required for(More)
We identified a new member of the phosducin-like (PhLP) protein family that is predominantly, if not exclusively, expressed in male and female germ cells. In situ analysis on testis sections and analysis of purified spermatogenic cell fractions evidenced a stage-specific expression with high levels of RNA and protein in pachytene spermatocytes and round(More)
Incubation of crude extracts from cells lytically infected with polyoma virus in the presence of periodate-oxidized [alpha-32P]ATP led to the radioactive labeling of one main polypeptide immunoprecipitated by anti-T antigen antibodies. It was absent from extracts of mock-infected cells and exhibited an apparent Mr value of 105,000, identical with that of(More)
Tumour-specific antigens (TSA; ref. 1) have been exploited in the diagnosis and imaging of human cancer and anti-TSA antibodies have therapeutic potential. Vaccination with TSA or anti-idiotypic (TSA) antibodies has also been used to control tumour growth in model systems. An effective immune response nevertheless demands copresentation of antigen with host(More)
Extracts prepared from either mouse cells or monkey cells were examined for the ability to support in vitro bovine papillomavirus type 1 (BPV1) DNA replication, and they were used in parallel as a source of host replication proteins for affinity chromatography. DNA synthesis exhibited an absolute requirement for BPV1 E1 protein. In contrast to previous(More)
Bovine papillomavirus E1 protein was found to be as efficient as the simian virus 40 large T antigen in initiating DNA synthesis in a cell-free system derived from COS1 cells. Multiple rounds of DNA synthesis occur, initiated at the bovine papillomavirus type 1 origin. Therefore, E1 functions in vitro as a lytic virus initiator.
We previously devised cell-free conditions supporting efficient replication of bovine papillomavirus type 1 (BPV1) DNA (C. Bonne-Andréa, S. Santucci, and P. Clertant, J. Virol. 69:3201-3205, 1995): the use of highly active preparations of viral initiator protein E1, together with extract from a particular cell source, allowed the synthesis of complete DNA(More)
The E1 open reading frame (ORF) of bovine papillomavirus type 1 is required for the persistence of viral genomes as multicopy plasmid molecules in transformed rodent fibroblasts. E1 has been reported to contain two separate complementation groups (M and R, corresponding to N- and C-terminal domains, respectively) which regulate viral replication. However,(More)
Binding of nucleotides to a specific site of the large T proteins of polyoma and SV40 viruses was demonstrated by covalent affinity labeling with periodate-oxidized [alpha-32P]ATP (oxATP) (Clertant, P., and Cuzin, F. (1982) J. Biol. Chem. 257, 6300-6305). This site appears different from the catalytic site of these proteins for ATP hydrolysis: (i)(More)
Replication of bovine papillomavirus type 1 (BPV-1) DNA has been shown to require two viral proteins known to interact in a molecular complex: E2, a transcription activator, and E1, another nuclear phosphoprotein, which binds to the replication origin and for which helicase/ATPase activities have previously been reported. Here we characterize the BPV-1 E1(More)