Polycystin-1 regulates actin cytoskeleton organization and directional cell migration through a novel PC1-Pacsin 2-N-Wasp complex

Abstract

How epithelial cells form a tubule with defined length and lumen diameter remains a fundamental question in cell and developmental biology. Loss of control of tubule lumen size in multiple organs including the kidney, liver and pancreas features polycystic kidney disease (PKD). To gain insights into autosomal dominant polycystic kidney disease, we performed yeast two-hybrid screens using the C-terminus of polycystin-1 (PC1) as bait. Here, we report that PC1 interacts with Pacsin 2, a cytoplasmic phosphoprotein that has been implicated in cytoskeletal organization, vesicle trafficking and more recently in cell intercalation during gastrulation. PC1 binds to a 107-residue fragment containing the α3 helix of the F-BAR domain of Pacsin 2 via a coiled-coil domain in its C-tail. PC1 and Pacsin 2 co-localize on the lamellipodia of migrating kidney epithelial cells. PC1 and Pacsin 2-deficient kidney epithelial cells migrate at a slower speed with reduced directional persistency. We further demonstrate that PC1, Pacsin 2 and N-Wasp are in the same protein complex, and both PC1 and Pacsin 2 are required for N-Wasp/Arp2/3-dependent actin remodeling. We propose that PC1 modulates actin cytoskeleton rearrangements and directional cell migration through the Pacsin 2/N-Wasp/Arp2/3 complex, which consequently contributes to the establishment and maintenance of the sophisticated tubular architecture. Disruption of this complex contributes to cyst formation in PKD.

Polycystic Kidney Disease with Steatocystoma Multiplex: Evidences for a Disruptive Effect of Mutated Polycystin-1 on Keratin 17 Polymerisation

“…Similar changes were also observed in keratinocytes from patients with SM associated with pachyonychia congenita type 2 (1). Polycystin-1 (PC1) is a large (~4,302 residues) integral membrane with 11 transmembrane domains (7). The PC1-Pacsin 2-N-Wasp complex is thought to contribute to the formation and maintenance of normal kidney tubular structures (7).…”

“…Polycystin-1 (PC1) is a large (~4,302 residues) integral membrane with 11 transmembrane domains (7). The PC1-Pacsin 2-N-Wasp complex is thought to contribute to the formation and maintenance of normal kidney tubular structures (7). The putative role of PC1 in epidermis is unknown (8).…”

The Future of Polycystic Kidney Disease Research—As Seen By the 12 Kaplan Awardees

“…59 We recently found that PC1 is present in the lamellipodia in migrating kidney tubular epithelial cells. 67 binds to an F-bar protein Pacsin 2 and regulates Pacsin 2 interaction with NWasp, an activator of the actin nucleator Arp2/3 protein complex. We found that disorganization of the actin cytoskeleton is a feature of PKD in vivo and that a novel PC1-Pacsin 2-N-Wasp complex is required for the actin remodeling and directional cell migration.…”

“…We found that disorganization of the actin cytoskeleton is a feature of PKD in vivo and that a novel PC1-Pacsin 2-N-Wasp complex is required for the actin remodeling and directional cell migration. 67 Directional cell migration is essential for the regeneration and maintenance of the epithelium and kidney development. 68 We propose that a defective actin cytoskeleton and directional cell migration contributes cyst formation.…”

Neuroproteomics and Systems Biology Approach to Identify Temporal Biomarker Changes Post Experimental Traumatic Brain Injury in Rats

“…Although its function in TBI is still unclear, a study has revealed the involvement of PACSIN in signal transduction to the cytoskeleton of neurons through phosphorylation by protein kinase C and casein kinase 2 (80–82). Importantly, this phosphorylation of casein kinase 2 has been proven to precipitate Rac1-dependent spine formation in dendrites of hippocampal neurons (83).…”