Biomaterial Database

Human papillomavirus 16 E7 protein is associated with the nuclear matrix. 1991

I Greenfield, and J Nickerson, and S Penman, and M Stanley

Department of Pathology, University of Cambridge, United Kingdom.

The cellular localization of the human papillomavirus (HPV)-16 E7 gene product in the cell lines CaSki and SiHa has been determined by both biochemical and immunocytochemical methods. These measurements show E7 to be localized in the cell nucleus, specifically with the nonchromatin nuclear structure or nuclear matrix. This localization of E7 required an unambiguous fractionation of the nuclear constituents. This was achieved by using a gentle sequential fractionation procedure to prepare the scaffold consisting of the nuclear matrix and intermediate filaments (NM-IF). Chromatin was cleaved with nuclease and the resulting nucleosomes eluted with 0.25 M ammonium sulfate. Immunostaining of cells after this extraction procedure with monoclonal antibodies (mAbs) to E7 revealed a fine grained, punctate nuclear fluorescence in CaSki and SiHa, which was absent in normal cervical keratinocytes and the HPV-negative cell line C33.1. Western blots of cell fractions with these mAbs showed that E7 was localized in the NM-IF fraction in SiHa and CaSki but was not detected in HPV-negative cells. A second protein of slightly higher mobility is identified by these antisera in HPV-16-containing cells. The data suggest that the previous inability to directly visualize E7 by immunocytology is due to the masking of epitopes by cellular components and not to low levels of protein.

UI	MeSH Term	Description	Entries
D007150	Immunohistochemistry	Histochemical localization of immunoreactive substances using labeled antibodies as reagents.	Immunocytochemistry,Immunogold Techniques,Immunogold-Silver Techniques,Immunohistocytochemistry,Immunolabeling Techniques,Immunogold Technics,Immunogold-Silver Technics,Immunolabeling Technics,Immunogold Silver Technics,Immunogold Silver Techniques,Immunogold Technic,Immunogold Technique,Immunogold-Silver Technic,Immunogold-Silver Technique,Immunolabeling Technic,Immunolabeling Technique,Technic, Immunogold,Technic, Immunogold-Silver,Technic, Immunolabeling,Technics, Immunogold,Technics, Immunogold-Silver,Technics, Immunolabeling,Technique, Immunogold,Technique, Immunogold-Silver,Technique, Immunolabeling,Techniques, Immunogold,Techniques, Immunogold-Silver,Techniques, Immunolabeling
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D009856	Oncogene Proteins, Viral	Products of viral oncogenes, most commonly retroviral oncogenes. They usually have transforming and often protein kinase activities.	Viral Oncogene Proteins,Viral Transforming Proteins,v-onc Proteins,Transforming Proteins, Viral,v onc Proteins
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D005455	Fluorescent Antibody Technique	Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.	Antinuclear Antibody Test, Fluorescent,Coon's Technique,Fluorescent Antinuclear Antibody Test,Fluorescent Protein Tracing,Immunofluorescence Technique,Coon's Technic,Fluorescent Antibody Technic,Immunofluorescence,Immunofluorescence Technic,Antibody Technic, Fluorescent,Antibody Technics, Fluorescent,Antibody Technique, Fluorescent,Antibody Techniques, Fluorescent,Coon Technic,Coon Technique,Coons Technic,Coons Technique,Fluorescent Antibody Technics,Fluorescent Antibody Techniques,Fluorescent Protein Tracings,Immunofluorescence Technics,Immunofluorescence Techniques,Protein Tracing, Fluorescent,Protein Tracings, Fluorescent,Technic, Coon's,Technic, Fluorescent Antibody,Technic, Immunofluorescence,Technics, Fluorescent Antibody,Technics, Immunofluorescence,Technique, Coon's,Technique, Fluorescent Antibody,Technique, Immunofluorescence,Techniques, Fluorescent Antibody,Techniques, Immunofluorescence,Tracing, Fluorescent Protein,Tracings, Fluorescent Protein
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D015153	Blotting, Western	Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.	Immunoblotting, Western,Western Blotting,Western Immunoblotting,Blot, Western,Immunoblot, Western,Western Blot,Western Immunoblot,Blots, Western,Blottings, Western,Immunoblots, Western,Immunoblottings, Western,Western Blots,Western Blottings,Western Immunoblots,Western Immunoblottings
D015530	Nuclear Matrix	The residual framework structure of the CELL NUCLEUS that maintains many of the overall architectural features of the cell nucleus including the nuclear lamina with NUCLEAR PORE complex structures, residual CELL NUCLEOLI and an extensive fibrogranular structure in the nuclear interior. (Advan. Enzyme Regul. 2002; 42:39-52)	Nuclear Scaffold,Nucleoskeleton,Matrices, Nuclear,Matrix, Nuclear,Nuclear Matrices,Nuclear Scaffolds,Nucleoskeletons,Scaffold, Nuclear,Scaffolds, Nuclear
D050725	Papillomavirus E7 Proteins	ONCOGENE PROTEINS from papillomavirus that deregulate the CELL CYCLE of infected cells and lead to NEOPLASTIC CELL TRANSFORMATION. Papillomavirus E7 proteins have been shown to interact with various regulators of the cell cycle including RETINOBLASTOMA PROTEIN and certain cyclin-dependent kinase inhibitors.	E7 Oncogene Proteins,Oncogene Protein E7, Papillomavirus,E7 Proteins, Papillomavirus,Oncogene Proteins, E7
D027383	Papillomaviridae	A family of small, non-enveloped DNA viruses infecting birds and most mammals, especially humans. They are grouped into multiple genera, but the viruses are highly host-species specific and tissue-restricted. They are commonly divided into hundreds of papillomavirus "types", each with specific gene function and gene control regions, despite sequence homology. Human papillomaviruses are found in the genera ALPHAPAPILLOMAVIRUS; BETAPAPILLOMAVIRUS; GAMMAPAPILLOMAVIRUS; and MUPAPILLOMAVIRUS.