Polycystin:In vitrosynthesis,in vivotissue expression, and subcellular localization identifies a large membrane-associated protein
Open Access
- 10 June 1997
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences of the United States of America
- Vol. 94 (12), 6397-6402
- https://doi.org/10.1073/pnas.94.12.6397
Abstract
The primary structure of polycystin predicts a large integral membrane protein with multiple cell recognition motifs, but its function remains unknown. Insight into polycystin’s normal function and its role in the development of autosomal dominant polycystic kidney disease (PKD1) requires the assembly of an extensive collection of molecular reagents to examine its expression and create model systems for functional studies. Development of these crucial reagents has been complicated due to the presence of transcriptionally active homologous loci. We have assembled the authentic full-length PKD1 cDNA and demonstrated expression of polycystin in vitro. Polyclonal antibodies directed against distinct extra- and intracellular domains specifically immunoprecipitated in vitro translated polycystin. The panel of antibodies was used to determine localization of polycystin in renal epithelial and endothelial cell lines and tissues of fetal, adult, and cystic origins. In normal adult kidney and maturing fetal nephrons, polycystin expression was confined to epithelial cells of the distal nephron and vascular endothelial cells. Expression in the proximal nephron was only observed after injury-induced cell proliferation. Polycystin expression was confined to ductal epithelium in liver, pancreas, and breast, and restricted to astrocytes in normal brain. We report clear evidence for the membrane localization of polycystin by both tissue sections and by confocal microscopy in cultured renal and endothelial cells. Interestingly, when cultured cells made cell–cell contact, polycystin was localized to the lateral membranes of cells in contact. These data suggest that polycystin is likely to have a widespread role in epithelial cell differentiation and maturation and in cell–cell interactions.Keywords
This publication has 31 references indexed in Scilit:
- A GTPase Controlling Nuclear Trafficking: Running the Right Way or Walking RANdomly?Cell, 1996
- PKD2 , a Gene for Polycystic Kidney Disease That Encodes an Integral Membrane ProteinScience, 1996
- A dominant mutation in the Ikaros gene leads to rapid development of leukemia and lymphomaCell, 1995
- Polycystic kidney disease: The complete structure of the PKD1 gene and its proteinCell, 1995
- Autosomal dominant polycystic kidney disease: Localization of the second gene to chromosome 4q13–q23Genomics, 1993
- Identification and Partial Characterization of a Candidate Gene for X-Linked Retinopathies Using a Lateral ApproachGenomics, 1993
- Polycystic kidney disease: Primary extracellular matrix abnormality or defective cellular differentiation?Kidney International, 1993
- A highly polymorphic DNA marker linked to adult polycystic kidney disease on chromosome 16Nature, 1985
- Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications.Proceedings of the National Academy of Sciences, 1979
- Cleavage of Structural Proteins during the Assembly of the Head of Bacteriophage T4Nature, 1970