title: [Prekeratin expression of simple epithelia in the cells of long-term cultured epithelial lines of the rat liver].
abstract: Prekeratin of simple epithelia with m.m. 55 kD (PK55) was found in all the studied tumorigenic and non-tumorigenic liver epithelial cell lines of the IAR series by means of indirect immunofluorescent methods in combination with corresponding monoclonal antibodies. The most prominent expression was observed in some tumorigenic cell lines. Expression of PK55 was reversible--the cells lost prekeratin in low density cultures. It has been found that the synthesis of prekeratins with m.m. 49 kD (PK49) and 40 kD (PK40) began on reaching higher cell densities than those needed for PK55 synthesis in IAR6-7 line. The PK40 appeared in cells spread on the substratum, while the PK49 was observed in upper poorly spread cells of ridges in multilayered dense cultures. Thus, the synthesis of prekeratins is not constitutive at least for some types of epithelial cells. Specific cell-to-cell interactions are presumably needed for each particular prekeratin synthesis induction.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000032:analysis; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000378:metabolism / Q000473:pathology; D002478:Cells, Cultured; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D005786:Gene Expression Regulation; D007381:Intermediate Filament Proteins / Q000096:biosynthesis* / Q000276:immunology; D007633:Keratins / Q000096:biosynthesis* / Q000276:immunology; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D008970:Molecular Weight; D011498:Protein Precursors / Q000096:biosynthesis* / Q000276:immunology; D051381:Rats; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; D007381:Intermediate Filament Proteins; D011498:Protein Precursors; C004818:prekeratin; D007633:Keratins
vernacular_title: Ekspressiia prekeratinov prostykh épiteliĭ v kletkakh dlitel'no kul'tiviruemykh épitelial'nykh liniĭ pecheni krys.