J Biol Chem. 2002 Jun 7;277(23):20763-73. Epub 2002 Mar 18.
Identification, characterization, and localization of a novel kidney polycystin-1-polycystin-2 complex.
Newby, L. J., Streets, A. J., Zhao, Y., Harris, P. C., Ward, C. J., Ong, A. C.,
["Sheffield Kidney Institute, University Section of Medicine, Division of Clinical Sciences, University of Sheffield, Sheffield S5 7AU, United Kingdom."]
["Sheffield Kidney Institute, University Section of Medicine, Division of Clinical Sciences, University of Sheffield, Sheffield S5 7AU, United Kingdom."]
The functions of the two proteins defective in autosomal dominant polycystic kidney disease, polycystin-1 and polycystin-2, have not been fully clarified, but it has been hypothesized that they may heterodimerize to form a "polycystin complex" involved in cell adhesion. In this paper, we demonstrate for the first time the existence of a native polycystin complex in mouse kidney tubular cells transgenic for PKD1, non-transgenic kidney cells, and normal adult human kidney. Polycystin-1 is heavily N-glycosylated, and several glycosylated forms of polycystin-1 differing in their sensitivity to endoglycosidase H (Endo H) were found; in contrast, native polycystin-2 was fully Endo H-sensitive. Using highly specific antibodies to both proteins, we show that polycystin-2 associates selectively with two species of full-length polycystin-1, one Endo H-sensitive and the other Endo H-resistant; importantly, the latter could be further enriched in plasma membrane fractions and co-immunoprecipitated with polycystin-2. Finally, a subpopulation of this complex co-localized to the lateral cell borders of PKD1 transgenic kidney cells. These results demonstrate that polycystin-1 and polycystin-2 interact in vivo to form a stable heterodimeric complex and suggest that disruption of this complex is likely to be of primary relevance to the pathogenesis of cyst formation in autosomal dominant polycystic kidney disease.
PMID: 11901144
 Screening
Validation: In vitro validation
Validation: In vivo validation
Characterization
Functional consequence
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Validation: In vivo validation
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| Assay with endogenous proteins | Assay with overexpressed proteins | Reference | ||||||||
| Cell or tissue | Cell or tissue | TRP channel construct | Interactor construct | |||||||
| TRP channel | Interactor | Method | Species | Region | Species | Region | ||||
| TRPP1 |
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PKD1/Polycystin-1 | Co-immunoprecipitation | COS-1 | 11901144 | |||||
| TRPP1 |
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PKD1/Polycystin-1 | Co-immunoprecipitation | Human kidney lysates | 11901144 | |||||
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