| Title: |
A Ciliary Phosphoinositide Pathway Regulates the Dosage of Polycystins in Primary Cilia |
| Authors: |
Chen, Chuan; Wang, Zhifei; Gao, Yue; Ellis, Madilyn R.; Ji, Biyun; Sieben, Cynthia J.; Haycraft, Courtney J.; Croyle, Mandy; Aghevli, Ariana; Xu, Qingwen; Robichaud, Jielu H.; He, Kai; Chen, Chunhua; Huang, Yan; Yoder, Bradley K.; Hu, Jinghua; Harris, Peter C.; Yu, Yong; Ling, Kun |
| Contributors: |
U.S. Department of Defense; National Institute of Diabetes and Digestive and Kidney Diseases; Pilot and Feasibility sub-awards from Mayo Clinic Translational PKD Center; Baltimore PKD Center; NIDDK; U54 center grant to Maryland PKD Research and Translation Core Center; Center for Individualized Medicine, Mayo Clinic |
| Source: |
Journal of the American Society of Nephrology ; ISSN 1046-6673 1533-3450 |
| Publisher Information: |
Ovid Technologies (Wolters Kluwer Health) |
| Publication Year: |
2025 |
| Description: |
Key Points Inositol polyphosphate-5-phosphatase E (INPP5E) and type Ig phosphatidylinositol-4-phosphate 5-kinase (PIPKIγ) coordinated the homeostasis of phosphatidylinositol-4-phosphate and phosphatidylinositol-4,5-bisphosphate in primary cilia. Modulating INPP5E or PIPKIγ activity changed the level of polycystin-1 and polycystin-2 in primary cilia. INPP5E inhibition increased the hypomorphic PKD1 variants (PC1-R3277C) in cilia and reduced cystogenesis in the kidney in vitro . Background Autosomal dominant polycystic kidney disease is mainly caused by mutations in PKD1 and PKD2 , which encode polycystin-1 (PC1) and polycystin-2 (PC2), respectively. PC1 and PC2 assemble a cation channel complex enriched in primary cilium, a sensory organelle associated with various developmental diseases, including polycystic kidney disease (PKD). Accumulating evidence supports the necessity of functional polycystin (PC) complex in cilia to prevent cystogenesis in the kidney, indicating that improving their ciliary levels may ameliorate defects underlying PKD pathogenesis. Yet, molecular mechanisms underlying the ciliary targeting and homeostasis of the PC complex are not fully understood. Methods Indirect immunofluorescence microscopy was used to monitor ciliary levels of PC1 and PC2 in renal epithelial cells. Electrophysiology analysis in oocytes was used to determine the channel activity of the PC complex. Cystogenesis in the kidney was measured using in vitro 3D-Matrigel cell models and ex vivo mouse embryonic kidney models. Results Suppressing inositol polyphosphate-5-phosphatase E (INPP5E) or activating type Ig phosphatidylinositol-4-phosphate 5-kinase raised ciliary levels of the PC complex in both normal renal epithelial cells and cells carrying autosomal dominant polycystic kidney disease mutations that interrupt the trafficking of PCs into cilia, including GANAB inactivation and the trafficking PKD1 mutation p.Arg3277Cys (RC). PC1 RC formed a complex with PC2 and exhibited normal channel activity in vitro . An INPP5E ... |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| DOI: |
10.1681/asn.0000000942 |
| DOI: |
10.1681/ASN.0000000942 |
| Availability: |
https://doi.org/10.1681/asn.0000000942; https://journals.lww.com/10.1681/ASN.0000000942 |
| Accession Number: |
edsbas.8AE8D06 |
| Database: |
BASE |