More than colocalizing with polycystin-1, polycystin-L is in the centrosome.
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.
Bui-Xuan
Eva-Flore
EF
Département de Physiologie et Biophysique, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec, Canada.
Li
Qiang
Q
Chen
Xing-Zhen
XZ
Boucher
Catherine A
CA
Sandford
Richard
R
Zhou
Jing
J
Basora
Nuria
N
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*
D015220:Calcium Channels; D008562:Membrane Glycoproteins; D010750:Phosphoproteins; D011956:Receptors, Cell Surface; D050396:TRPP Cation Channels; C486487:Pkd2l1 protein, mouse; C512699:polycystin-L, rat