title: More than colocalizing with polycystin-1, polycystin-L is in the centrosome.
abstract: Polycystin-1 and polycystin-2 are involved in autosomal dominant polycystic kidney disease by unknown mechanisms. These two proteins are located in primary cilia where they mediate mechanosensation, suggesting a link between cilia function and renal disease. In this study, we sought to characterize the subcellular localization of polycystin-L, a closely related member of polycystin-2, in epithelial renal cell lines. We have shown that endogenous polycystin-l subcellular distribution is different in proliferative and nonproliferative cultures. Polycystin-L is found mostly in the endoplasmic reticulum in subconfluent cell cultures, while in confluent cells it is redistributed to sites of cell-cell contact and to the primary cilium as is polycystin-1. Subcellular fractionation confirmed a common distribution of polycystin-L and polycystin-1 in the fractions corresponding to those containing the plasma membrane of postconfluent cells. Reciprocal coimmunoprecipitation experiments showed that polycystin-L was associated with polycystin-1 in a common complex in both subconfluent and confluent cell cultures. Interestingly, we also identified a novel site for a polycystin member (polycystin-L) in unciliated cells, the centrosome, which allowed us to reveal an involvement of polycystin-l in cell proliferation.
authors.affiliation: Département de Physiologie et Biophysique, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec, Canada.
authors.forename: Eva-Flore
authors.initials: EF
authors.lastname: Bui-Xuan
authors.forename: Qiang
authors.initials: Q
authors.lastname: Li
authors.forename: Xing-Zhen
authors.initials: XZ
authors.lastname: Chen
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Boucher
authors.forename: Richard
authors.initials: R
authors.lastname: Sandford
authors.forename: Jing
authors.initials: J
authors.lastname: Zhou
authors.forename: Nuria
authors.initials: N
authors.lastname: Basora
mesh_terms: D000818:Animals; D015220:Calcium Channels; D002460:Cell Line; D002462:Cell Membrane / Q000737:chemistry / Q000502:physiology; D049109:Cell Proliferation; D018385:Centrosome / Q000737:chemistry* / Q000502:physiology; D002923:Cilia / Q000737:chemistry / Q000502:physiology; D004285:Dogs; D004721:Endoplasmic Reticulum / Q000737:chemistry / Q000502:physiology; D004847:Epithelial Cells / Q000737:chemistry / Q000166:cytology / Q000502:physiology; D007150:Immunohistochemistry; D007668:Kidney / Q000737:chemistry / Q000166:cytology / Q000502:physiology; D007685:Kidney Tubules, Collecting / Q000737:chemistry / Q000166:cytology / Q000502:physiology; D008562:Membrane Glycoproteins / Q000032:analysis; D051379:Mice; D010750:Phosphoproteins / Q000032:analysis; D051381:Rats; D011956:Receptors, Cell Surface; D050396:TRPP Cation Channels / Q000032:analysis*
chemical_list: D015220:Calcium Channels; D008562:Membrane Glycoproteins; D010750:Phosphoproteins; D011956:Receptors, Cell Surface; D050396:TRPP Cation Channels; C486487:Pkd2l1 protein, mouse; C512699:polycystin-L, rat