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Reddy Palicharla V, Mukhopadhyay S. Molecular and structural perspectives on protein trafficking to the primary cilium membrane. Biochem Soc Trans 2024; 52:1473-1487. [PMID: 38864436 DOI: 10.1042/bst20231403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 05/23/2024] [Accepted: 05/24/2024] [Indexed: 06/13/2024]
Abstract
The primary cilium is a dynamic subcellular compartment templated from the mother centriole or basal body. Cilia are solitary and tiny, but remarkably consequential in cellular pathways regulating proliferation, differentiation, and maintenance. Multiple transmembrane proteins such as G-protein-coupled receptors, channels, enzymes, and membrane-associated lipidated proteins are enriched in the ciliary membrane. The precise regulation of ciliary membrane content is essential for effective signal transduction and maintenance of tissue homeostasis. Surprisingly, a few conserved molecular factors, intraflagellar transport complex A and the tubby family adapter protein TULP3, mediate the transport of most membrane cargoes into cilia. Recent advances in cryogenic electron microscopy provide fundamental insights into these molecular players. Here, we review the molecular players mediating cargo delivery into the ciliary membrane through the lens of structural biology. These mechanistic insights into ciliary transport provide a framework for understanding of disease variants in ciliopathies, enable precise manipulation of cilia-mediated pathways, and provide a platform for the development of targeted therapeutics.
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Affiliation(s)
- Vivek Reddy Palicharla
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, U.S.A
| | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, U.S.A
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2
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Tham MS, Cottle DL, Zylberberg AK, Short KM, Jones LK, Chan P, Conduit SE, Dyson JM, Mitchell CA, Smyth IM. Deletion of Aurora kinase A prevents the development of polycystic kidney disease in mice. Nat Commun 2024; 15:371. [PMID: 38191531 PMCID: PMC10774271 DOI: 10.1038/s41467-023-44410-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 12/09/2023] [Indexed: 01/10/2024] Open
Abstract
Aurora Kinase A (AURKA) promotes cell proliferation and is overexpressed in different types of polycystic kidney disease (PKD). To understand AURKA's role in regulating renal cyst development we conditionally deleted the gene in mouse models of Autosomal Dominant PKD (ADPKD) and Joubert Syndrome, caused by Polycystin 1 (Pkd1) and Inositol polyphosphate-5-phosphatase E (Inpp5e) mutations respectively. We show that while Aurka is dispensable for collecting duct development and homeostasis, its deletion prevents cyst formation in both disease models. Cross-comparison of transcriptional changes implicated AKT signaling in cyst prevention and we show that (i) AURKA and AKT physically interact, (ii) AURKA regulates AKT activity in a kinase-independent manner and (iii) inhibition of AKT can reduce disease severity. AKT activation also regulates Aurka expression, creating a feed-forward loop driving renal cystogenesis. We find that the AURKA kinase inhibitor Alisertib stabilises the AURKA protein, agonizing its cystogenic functions. These studies identify AURKA as a master regulator of renal cyst development in different types of PKD, functioning in-part via AKT.
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Affiliation(s)
- Ming Shen Tham
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Denny L Cottle
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
| | - Allara K Zylberberg
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Kieran M Short
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Lynelle K Jones
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Perkin Chan
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Sarah E Conduit
- Cancer Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Jennifer M Dyson
- Cancer Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Christina A Mitchell
- Cancer Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Ian M Smyth
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
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Yanda MK, Ciobanu C, Guggino WB, Cebotaru L. CFTR and PC2, partners in the primary cilia in autosomal dominant polycystic kidney disease. Am J Physiol Cell Physiol 2023; 325:C682-C693. [PMID: 37519231 PMCID: PMC10635646 DOI: 10.1152/ajpcell.00197.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 07/13/2023] [Accepted: 07/27/2023] [Indexed: 08/01/2023]
Abstract
Defects in the primary cilium are associated with autosomal dominant polycystic kidney disease (ADPKD). We used a combination of animal models, Western blotting, and confocal microscopy and discovered that CFTR and polycystin 2 (PC2) are both colocalized to the cilium in normal kidneys, with the levels of both being decreased in cystic epithelia. Cilia were longer in CFTR-null mice and in cystic cells in our ADPKD animal models. We examined septin 2, known to play a role in cilia length, to act as a diffusion barrier and to serve as an enhancer of proliferation. We found that septin 2 protein levels were upregulated and colocalized strongly with CFTR in cystic cells. Application of VX-809, the CFTR corrector, restored CFTR and PC2 toward normal in the cilia, decreased the protein levels of septin 2, and drastically reduced septin 2 colocalization with CFTR. Our data suggest that CFTR is present in the cilia and plays a role there, perhaps through its conductance of Cl-. We also postulate that septin 2 is important for localizing CFTR to the apical membrane in cystic epithelia.NEW & NOTEWORTHY CFTR is present in the primary cilia together with polycystin 2 (PC2). Ablation of CFTR makes cilia longer suggesting that CFTR plays a role there, perhaps through its conductance of Cl.
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Affiliation(s)
- Murali K Yanda
- The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Cristian Ciobanu
- The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - William B Guggino
- The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Liudmila Cebotaru
- The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
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4
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Van Sciver RE, Long AB, Katz HG, Gigante ED, Caspary T. Ciliary ARL13B inhibits developmental kidney cystogenesis in mouse. Dev Biol 2023; 500:1-9. [PMID: 37209936 PMCID: PMC10330881 DOI: 10.1016/j.ydbio.2023.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 05/15/2023] [Accepted: 05/17/2023] [Indexed: 05/22/2023]
Abstract
ARL13B is a small GTPase enriched in cilia. Deletion of Arl13b in mouse kidney results in renal cysts and an associated absence of primary cilia. Similarly, ablation of cilia leads to kidney cysts. To investigate whether ARL13B functions from within cilia to direct kidney development, we examined kidneys of mice expressing an engineered cilia-excluded ARL13B variant, ARL13BV358A. These mice retained renal cilia and developed cystic kidneys. Because ARL13B functions as a guanine nucleotide exchange factor (GEF) for ARL3, we examined kidneys of mice expressing an ARL13B variant that lacks ARL3 GEF activity, ARL13BR79Q. We found normal kidney development with no evidence of cysts in these mice. Taken together, our results show that ARL13B functions within cilia to inhibit renal cystogenesis during mouse development, and that this function does not depend on its role as a GEF for ARL3.
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Affiliation(s)
- Robert E Van Sciver
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA, 30322, USA.
| | - Alyssa B Long
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA, 30322, USA.
| | - Harrison G Katz
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA, 30322, USA; Department of Biology, Brown University, Providence, RI, 02912, USA.
| | - Eduardo D Gigante
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA, 30322, USA; Graduate Program in Neuroscience, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA, 30322, USA; Department of Biology, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
| | - Tamara Caspary
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA, 30322, USA.
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Ateshian GA, Spack KA, Hone JC, Azeloglu EU, Gusella GL. Computational study of biomechanical drivers of renal cystogenesis. Biomech Model Mechanobiol 2023; 22:1113-1127. [PMID: 37024601 PMCID: PMC10524738 DOI: 10.1007/s10237-023-01704-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 02/12/2023] [Indexed: 04/08/2023]
Abstract
Renal cystogenesis is the pathological hallmark of autosomal dominant polycystic kidney disease, caused by PKD1 and PKD2 mutations. The formation of renal cysts is a common manifestation in ciliopathies, a group of syndromic disorders caused by mutation of proteins involved in the assembly and function of the primary cilium. Cystogenesis is caused by the derailment of the renal tubular architecture and tissue deformation that eventually leads to the impairment of kidney function. However, the biomechanical imbalance of cytoskeletal forces that are altered in cells with Pkd1 mutations has never been investigated, and its nature and extent remain unknown. In this computational study, we explored the feasibility of various biomechanical drivers of renal cystogenesis by examining several hypothetical mechanisms that may promote morphogenetic markers of cystogenesis. Our objective was to provide physics-based guidance for our formulation of hypotheses and our design of experimental studies investigating the role of biomechanical disequilibrium in cystogenesis. We employed the finite element method to explore the role of (1) wild-type versus mutant cell elastic modulus; (2) contractile stress magnitude in mutant cells; (3) localization and orientation of contractile stress in mutant cells; and (4) sequence of cell contraction and cell proliferation. Our objective was to identify the factors that produce the characteristic tubular cystic growth. Results showed that cystogenesis occurred only when mutant cells contracted along the apical-basal axis, followed or accompanied by cell proliferation, as long as mutant cells had comparable or lower elastic modulus than wild-type cells, with their contractile stresses being significantly greater than their modulus. Results of these simulations allow us to focus future in vitro and in vivo experimental studies on these factors, helping us formulate physics-based hypotheses for renal tubule cystogenesis.
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Affiliation(s)
- Gerard A Ateshian
- Department of Mechanical Engineering, Columbia University, New York, NY, USA.
- Department of Biomedical Engineering, Columbia University, New York, NY, USA.
| | - Katherine A Spack
- Department of Biomedical Engineering, Columbia University, New York, NY, USA
| | - James C Hone
- Department of Mechanical Engineering, Columbia University, New York, NY, USA
| | - Evren U Azeloglu
- Department of Medicine, Division of Nephrology, Mount Sinai School of Medicine, New York, NY, USA
- Department of Pharmacological Sciences, Mount Sinai School of Medicine, New York, NY, USA
| | - G Luca Gusella
- Department of Medicine, Division of Nephrology, Mount Sinai School of Medicine, New York, NY, USA
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Van Sciver RE, Long AB, Katz HG, Gigante ED, Caspary T. Ciliary ARL13B inhibits developmental kidney cystogenesis in mouse. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.08.527739. [PMID: 36798281 PMCID: PMC9934666 DOI: 10.1101/2023.02.08.527739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
ARL13B is a small GTPase enriched in cilia. Deletion of Arl13b in mouse kidney results in renal cysts and an associated absence of primary cilia. Similarly, ablation of cilia leads to kidney cysts. To investigate whether ARL13B functions from within cilia to direct kidney development, we examined kidneys of mice expressing an engineered cilia-excluded ARL13B variant, ARL13BV358A. These mice retained renal cilia and developed cystic kidneys. Because ARL13B functions as a guanine nucleotide exchange factor (GEF) for ARL3, we examined kidneys of mice expressing an ARL13B variant that lacks ARL3 GEF activity, ARL13BR79Q. We found normal kidney development with no evidence of cysts in these mice. Taken together, our results show that ARL13B functions within cilia to inhibit renal cystogenesis during mouse development, and that this function does not depend on its role as a GEF for ARL3.
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Affiliation(s)
- Robert E. Van Sciver
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA
| | - Alyssa B. Long
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA
| | - Harrison G. Katz
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA
- Present address: Department of Biology, Brown University, Providence, RI 02912, USA
| | - Eduardo D. Gigante
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA
- Graduate Program in Neuroscience, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA
- Present address: Department of Biology, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Tamara Caspary
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA
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Palicharla VR, Hwang SH, Somatilaka BN, Legué E, Shimada IS, Familiari NE, Tran VM, Woodruff JB, Liem KF, Mukhopadhyay S. Interactions between TULP3 tubby domain and ARL13B amphipathic helix promote lipidated protein transport to cilia. Mol Biol Cell 2023; 34:ar18. [PMID: 36652335 PMCID: PMC10011728 DOI: 10.1091/mbc.e22-10-0473] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The primary cilium is a nexus for cell signaling and relies on specific protein trafficking for function. The tubby family protein TULP3 transports integral membrane proteins into cilia through interactions with the intraflagellar transport complex-A (IFT-A) and phosphoinositides. It was previously shown that short motifs called ciliary localization sequences (CLSs) are necessary and sufficient for TULP3-dependent ciliary trafficking of transmembrane cargoes. However, the mechanisms by which TULP3 regulates ciliary compartmentalization of nonintegral, membrane-associated proteins and whether such trafficking requires TULP3-dependent CLSs is unknown. Here we show that TULP3 is required for ciliary transport of the Joubert syndrome-linked palmitoylated GTPase ARL13B through a CLS. An N-terminal amphipathic helix, preceding the GTPase domain of ARL13B, couples with the TULP3 tubby domain for ciliary trafficking, irrespective of palmitoylation. ARL13B transport requires TULP3 binding to IFT-A but not to phosphoinositides, indicating strong membrane-proximate interactions, unlike transmembrane cargo transport requiring both properties of TULP3. TULP3-mediated trafficking of ARL13B also regulates ciliary enrichment of farnesylated and myristoylated downstream effectors of ARL13B. The lipidated cargoes show distinctive depletion kinetics from kidney epithelial cilia with relation to Tulp3 deletion-induced renal cystogenesis. Overall, these findings indicate an expanded role of the tubby domain in capturing analogous helical secondary structural motifs from diverse cargoes.
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Affiliation(s)
- Vivek Reddy Palicharla
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Sun-Hee Hwang
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | | | - Emilie Legué
- Vertebrate Developmental Biology Program, Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520
| | - Issei S Shimada
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Nicole E Familiari
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Vanna M Tran
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Jeffrey B Woodruff
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Karel F Liem
- Vertebrate Developmental Biology Program, Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520
| | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
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Li XW, Ran JH, Zhou H, He JZ, Qiu ZW, Wang SY, Wu MN, Zhu S, An YP, Ma A, Li M, Quan YZ, Li NN, Ren CQ, Yang BX. 1-Indanone retards cyst development in ADPKD mouse model by stabilizing tubulin and down-regulating anterograde transport of cilia. Acta Pharmacol Sin 2023; 44:406-420. [PMID: 35906293 PMCID: PMC9889777 DOI: 10.1038/s41401-022-00937-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 06/03/2022] [Indexed: 02/04/2023] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease. Cyst development in ADPKD involves abnormal epithelial cell proliferation, which is affected by the primary cilia-mediated signal transduction in the epithelial cells. Thus, primary cilium has been considered as a therapeutic target for ADPKD. Since ADPKD exhibits many pathological features similar to solid tumors, we investigated whether targeting primary cilia using anti-tumor agents could alleviate the development of ADPKD. Twenty-four natural compounds with anti-tumor activity were screened in MDCK cyst model, and 1-Indanone displayed notable inhibition on renal cyst growth without cytotoxicity. This compound also inhibited cyst development in embryonic kidney cyst model. In neonatal kidney-specific Pkd1 knockout mice, 1-Indanone remarkably slowed down kidney enlargement and cyst expansion. Furthermore, we demonstrated that 1-Indanone inhibited the abnormal elongation of cystic epithelial cilia by promoting tubulin polymerization and significantly down-regulating expression of anterograde transport motor protein KIF3A and IFT88. Moreover, we found that 1-Indanone significantly down-regulated ciliary coordinated Wnt/β-catenin, Hedgehog signaling pathways. These results demonstrate that 1-Indanone inhibits cystic cell proliferation by reducing abnormally prolonged cilia length in cystic epithelial cells, suggesting that 1-Indanone may hold therapeutic potential to retard cyst development in ADPKD.
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Affiliation(s)
- Xiao-Wei Li
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Jian-Hua Ran
- Department of Anatomy, College of Basic Medicine, Chongqing Medical University, Chongqing, 400016, China
| | - Hong Zhou
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Jin-Zhao He
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Zhi-Wei Qiu
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Shu-Yuan Wang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Meng-Na Wu
- Department of Anatomy, College of Basic Medicine, Chongqing Medical University, Chongqing, 400016, China
| | - Shuai Zhu
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Yong-Pan An
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Ang Ma
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Min Li
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Ya-Zhu Quan
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Nan-Nan Li
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Chao-Qun Ren
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Bao-Xue Yang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China.
- Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, 100191, China.
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9
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Girardet L, Cyr DG, Belleannée C. Arl13b controls basal cell stemness properties and Hedgehog signaling in the mouse epididymis. Cell Mol Life Sci 2022; 79:556. [PMID: 36261680 DOI: 10.1007/s00018-022-04570-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 09/09/2022] [Accepted: 09/22/2022] [Indexed: 11/30/2022]
Abstract
Epithelial cells orchestrate a series of intercellular signaling events in response to tissue damage. While the epididymis is composed of a pseudostratified epithelium that controls the acquisition of male fertility, the maintenance of its integrity in the context of tissue damage or inflammation remains largely unknown. Basal cells of the epididymis contain a primary cilium, an organelle that controls cellular differentiation in response to Hedgehog signaling cues. Hypothesizing its contribution to epithelial homeostasis, we knocked out the ciliary component ARL13B in keratin 5-positive basal cells. In this model, the reduced size of basal cell primary cilia was associated with impaired Hedgehog signaling and the loss of KRT5, KRT14, and P63 basal cell markers. When subjected to tissue injury, the epididymal epithelium from knock-out mice displayed imbalanced rates of cell proliferation/apoptosis and failed to properly regenerate in vivo. This response was associated with changes in the transcriptomic landscape related to immune response, cell differentiation, cell adhesion, and triggered severe hypoplasia of the epithelium. Together our results indicate that the ciliary GTPase, ARL13B, participates in the transduction of the Hedgehog signaling pathway to maintain basal cell stemness needed for tissue regeneration. These findings provide new insights into the role of basal cell primary cilia as safeguards of pseudostratified epithelia.
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Affiliation(s)
- Laura Girardet
- Faculty of Medicine, Department of Obstetrics, Gynecology and Reproduction, Université Laval, CHU de Québec Research Center (CHUL), Quebec City, QC, Canada
| | - Daniel G Cyr
- Faculty of Medicine, Department of Obstetrics, Gynecology and Reproduction, Université Laval, CHU de Québec Research Center (CHUL), Quebec City, QC, Canada.,Laboratory for Reproductive Toxicology, INRS-Centre Armand-Frappier Santé Biotechnologie, Université du Québec, Laval, QC, Canada
| | - Clémence Belleannée
- Faculty of Medicine, Department of Obstetrics, Gynecology and Reproduction, Université Laval, CHU de Québec Research Center (CHUL), Quebec City, QC, Canada.
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10
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Jafari Khamirani H, Palicharla VR, Dastgheib SA, Dianatpour M, Imanieh MH, Tabei SS, Besse W, Mukhopadhyay S, Liem KF. A pathogenic variant of TULP3 causes renal and hepatic fibrocystic disease. Front Genet 2022; 13:1021037. [PMID: 36276950 PMCID: PMC9585244 DOI: 10.3389/fgene.2022.1021037] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 09/22/2022] [Indexed: 11/26/2022] Open
Abstract
Patient variants in Tubby Like Protein-3 (TULP3) have recently been associated with progressive fibrocystic disease in tissues and organs. TULP3 is a ciliary trafficking protein that links membrane-associated proteins to the intraflagellar transport complex A. In mice, mutations in Tulp3 drive phenotypes consistent with ciliary dysfunction which include renal cystic disease, as part of a ciliopathic spectrum. Here we report two sisters from consanguineous parents with fibrocystic renal and hepatic disease harboring a homozygous missense mutation in TULP3 (NM_003324.5: c.1144C>T, p.Arg382Trp). The R382W patient mutation resides within the C-terminal Tubby domain, a conserved domain required for TULP3 to associate with phosphoinositides. We show that inner medullary collecting duct-3 cells expressing the TULP3 R382W patient variant have a severely reduced ability to localize the membrane-associated proteins ARL13b, INPP5E, and GPR161 to the cilium, consistent with a loss of TULP3 function. These studies establish Arginine 382 as a critical residue in the Tubby domain, which is essential for TULP3-mediated protein trafficking within the cilium, and expand the phenotypic spectrum known to result from recessive deleterious mutations in TULP3.
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Affiliation(s)
| | - Vivek Reddy Palicharla
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | | | - Mehdi Dianatpour
- Department of Medical Genetics, Shiraz University of Medical Sciences, Shiraz, Iran
- Stem Cells Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad Hadi Imanieh
- Gastroenterohepatology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Seyed Sajjad Tabei
- Shiraz Nephro-Urology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Whitney Besse
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, CT, United States
| | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Karel F. Liem
- Vertebrate Developmental Biology Program, Department of Pediatrics, Yale University School of Medicine, New Haven, CT, United States
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11
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Hsieh CL, Jerman SJ, Sun Z. Non-cell-autonomous activation of hedgehog signaling contributes to disease progression in a mouse model of renal cystic ciliopathy. Hum Mol Genet 2022; 31:4228-4240. [PMID: 35904445 PMCID: PMC9759329 DOI: 10.1093/hmg/ddac175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 07/10/2022] [Accepted: 07/26/2022] [Indexed: 01/21/2023] Open
Abstract
Polycystic kidney disease (PKD) is a ciliopathy characterized by fluid-filled epithelial cysts in the kidney. Although it is well established that the primary cilium is essential for hedgehog (HH) signaling and HH signaling is abnormally activated in multiple PKD models, the mechanism and function of HH activation in PKD pathogenesis remain incompletely understood. Here we used a transgenic HH reporter mouse line to identify the target tissue of HH signaling in Arl13f/f;Ksp-Cre mutant kidney, in which the cilia biogenesis gene Arl13b is specifically deleted in epithelial cells of the distal nephron. In addition, we used a co-culture system to dissect cross-talk between epithelial and mesenchymal cells in the absence of expanding cysts. Finally, we treated Arl13bf/f;Ksp-Cre mice with the GLI inhibitor GANT61 and analyzed its impact on PKD progression in this model. We found that deletion of Arl13b in epithelial cells in the mouse kidney, in vivo, led to non-cell-autonomous activation of the HH pathway in the interstitium. In vitro, when co-cultured with mesenchymal cells, Arl13b-/- epithelial cells produced more sonic hedgehog in comparison to cells expressing Arl13b. Reciprocally, HH signaling was activated in mesenchymal cells co-cultured with Arl13b-/- epithelial cells. Finally, whole body inhibition of the HH pathway by GANT61 reduced the number of proliferating cells, inhibited cyst progression and fibrosis and preserved kidney function in Arl13bf/f;Ksp-Cre mice. Our results reveal non-cell-autonomous activation of HH signaling in the interstitium of the Arl13bf/f;Ksp-Cre kidney and suggest that abnormal activation of the HH pathway contributes to disease progression.
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Affiliation(s)
- Chia-Ling Hsieh
- Department of Genetics, Yale University School of Medicine, 333 Cedar St., New Haven, CT 06520, USA
| | - Stephanie Justine Jerman
- Department of Genetics, Yale University School of Medicine, 333 Cedar St., New Haven, CT 06520, USA
| | - Zhaoxia Sun
- To whom correspondence should be addressed. Tel: +1 2037853589; Fax: +1 2037857227;
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12
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Walker RV, Maranto A, Palicharla VR, Hwang SH, Mukhopadhyay S, Qian F. Cilia-Localized Counterregulatory Signals as Drivers of Renal Cystogenesis. Front Mol Biosci 2022; 9:936070. [PMID: 35832738 PMCID: PMC9272769 DOI: 10.3389/fmolb.2022.936070] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 05/30/2022] [Indexed: 12/18/2022] Open
Abstract
Primary cilia play counterregulatory roles in cystogenesis—they inhibit cyst formation in the normal renal tubule but promote cyst growth when the function of polycystins is impaired. Key upstream cilia-specific signals and components involved in driving cystogenesis have remained elusive. Recent studies of the tubby family protein, Tubby-like protein 3 (TULP3), have provided new insights into the cilia-localized mechanisms that determine cyst growth. TULP3 is a key adapter of the intraflagellar transport complex A (IFT-A) in the trafficking of multiple proteins specifically into the ciliary membrane. Loss of TULP3 results in the selective exclusion of its cargoes from cilia without affecting their extraciliary pools and without disrupting cilia or IFT-A complex integrity. Epistasis analyses have indicated that TULP3 inhibits cystogenesis independently of the polycystins during kidney development but promotes cystogenesis in adults when polycystins are lacking. In this review, we discuss the current model of the cilia-dependent cyst activation (CDCA) mechanism in autosomal dominant polycystic kidney disease (ADPKD) and consider the possible roles of ciliary and extraciliary polycystins in regulating CDCA. We then describe the limitations of this model in not fully accounting for how cilia single knockouts cause significant cystic changes either in the presence or absence of polycystins. Based on available data from TULP3/IFT-A-mediated differential regulation of cystogenesis in kidneys with deletion of polycystins either during development or in adulthood, we hypothesize the existence of cilia-localized components of CDCA (cCDCA) and cilia-localized cyst inhibition (CLCI) signals. We develop the criteria for cCDCA/CLCI signals and discuss potential TULP3 cargoes as possible cilia-localized components that determine cystogenesis in kidneys during development and in adult mice.
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Affiliation(s)
- Rebecca V. Walker
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Anthony Maranto
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | | | - Sun-Hee Hwang
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, United States
| | - Saikat Mukhopadhyay
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, United States
| | - Feng Qian
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
- *Correspondence: Feng Qian,
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13
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Paschereit F, Schindelmann KH, Hummel M, Schneider J, Stoltenburg-Didinger G, Kaindl AM. Cerebral Abnormalities in Spina Bifida: A Neuropathological Study. Pediatr Dev Pathol 2022; 25:107-123. [PMID: 34614376 PMCID: PMC9109215 DOI: 10.1177/10935266211040500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Spina bifida (SB) is the most common neural tube defect in humans. Here, we analyzed systematically the neuropathological findings of the brain in SB cases. METHODS 79 cases with SB aperta (SBA) and 6 cases with SB occulta (SBO) autopsied at the Charité Neuropathology from 1974 to 2000 were re-evaluated retrospectively. For this, case files and spinal cord as well as brain sections were studied. RESULTS While no brain malformations were detected in SBO cases, 95% of SBA cases had brain malformations. Main brain anomalies identified were hydrocephalus (71%), Chiari II malformation (36%), heterotopia (34%), other cerebellar anomalies (36%), gyrification defects (33%), and ependymal denudation (29%). Hydrocephalus was observed as early as gestational week 17 and was highly associated to Chiari II and ependymal denudation. In 55% SBA was accompanied by further anomalies not primarily affecting the CNS. CONCLUSION We confirm using neuropathologic methods brain malformations in most SBA but none in SBO cases. In addition to our previous radiologic study, we now demonstrate the high prevalence of cerebellar malformations and cerebral heterotopias in SBA. The early detection of hydrocephalus and Chiari II malformation in fetuses raises the question whether these arise parallel rather than in strict temporal sequence.
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Affiliation(s)
- Fabienne Paschereit
- Institute of Cell Biology and Neurobiology, Charité—Universitätsmedizin Berlin, Berlin, Germany,Department of Pediatric Neurology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Kim Hannah Schindelmann
- Institute of Cell Biology and Neurobiology, Charité—Universitätsmedizin Berlin, Berlin, Germany,Department of Pediatric Neurology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Michael Hummel
- Institute of Pathology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Joanna Schneider
- Department of Pediatric Neurology, Charité—Universitätsmedizin Berlin, Berlin, Germany,Center for Chronically Sick Children (Sozialpädiatrisches Zentrum, SPZ), Charité—Universitätsmedizin Berlin, Berlin, Germany
| | | | - Angela M Kaindl
- Institute of Cell Biology and Neurobiology, Charité—Universitätsmedizin Berlin, Berlin, Germany,Department of Pediatric Neurology, Charité—Universitätsmedizin Berlin, Berlin, Germany,Center for Chronically Sick Children (Sozialpädiatrisches Zentrum, SPZ), Charité—Universitätsmedizin Berlin, Berlin, Germany,Angela M Kaindl, Department of Pediatric Neurology, Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany.
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14
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Yu SS, Wang E, Chiang CY, Cheng PH, Yeh YS, Wu YY, Chiou YY, Jiang ST. Large deletion of Wdr19 in developing renal tubules disrupts primary ciliogenesis leading to polycystic kidney disease in mice. J Pathol 2022; 257:5-16. [PMID: 35007346 DOI: 10.1002/path.5863] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 12/03/2021] [Accepted: 01/06/2022] [Indexed: 11/11/2022]
Abstract
WD repeat domain 19 (Wdr19) is a major component of the intraflagellar transport (IFT) machinery, which is involved in the function of primary cilia. However, the effects of Wdr19 on primary cilia formation, cystogenesis, and polycystic kidney disease (PKD) progression remain unclear. To study these effects, we generated three lines of kidney-specific conditional knockout mice: Wdr19-knockout (Wdr19-KO, Wdr19f/- ::Cdh16-CreTg/0 ), Pkd1-knockout (Pkd1-KO, Pkd1f/- ::Cdh16-CreTg/0 ), and Wdr19/Pkd1-double knockout (Wdr19&Pkd1-dKO, Wdr19f/- ;Pkd1f/- ::Cdh16-CreTg/0 ) mice. Ultrastructural analysis using transmission electron microscopy (TEM) indicated that the primary cilia were almost absent at postnatal day 10 in Wdr19-KO mice compared with Pkd1-KO and wild-type (WT) mice. However, the primary cilia appeared structurally normal even if malfunctional in Pkd1-deficient cysts. The Pkd1-KO mice had the most severe PKD progression, including the shortest lifespan (14 days) and the largest renal cysts, among the three knockout lines. Thus, the molecular mechanism of renal cystogenesis in Wdr19-KO mice (primary cilia abrogation) was different from that in Pkd1-KO mice (primary cilia malfunction). In summary, Wdr19 deficiency leads to primary cilia abrogation and renal cyst formation. Wdr19 is primarily proposed to participate in retrograde IFT and to be crucial for the construction of primary cilia, which are critical organelles for tubulogenesis in the developing kidneys. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Shang-Shiuan Yu
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, 70457, Taiwan.,National Laboratory Animal Center, National Applied Research Laboratories, Tainan, 74147, Taiwan
| | - Ellian Wang
- Department of Physiology, National Cheng Kung University Medical College, Tainan, 70101, Taiwan
| | - Chih-Ying Chiang
- National Laboratory Animal Center, National Applied Research Laboratories, Tainan, 74147, Taiwan
| | - Po-Hao Cheng
- National Laboratory Animal Center, National Applied Research Laboratories, Tainan, 74147, Taiwan
| | - Yu-Shan Yeh
- National Laboratory Animal Center, National Applied Research Laboratories, Tainan, 74147, Taiwan
| | - Ying-Ying Wu
- National Laboratory Animal Center, National Applied Research Laboratories, Tainan, 74147, Taiwan
| | - Yuan-Yow Chiou
- National Laboratory Animal Center, National Applied Research Laboratories, Tainan, 74147, Taiwan.,Division of Pediatric Nephrology, Department of Pediatrics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, 70403, Taiwan
| | - Si-Tse Jiang
- National Laboratory Animal Center, National Applied Research Laboratories, Tainan, 74147, Taiwan
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15
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Suciu SK, Long AB, Caspary T. Smoothened and ARL13B are critical in mouse for superior cerebellar peduncle targeting. Genetics 2021; 218:6300527. [PMID: 34132778 PMCID: PMC8864748 DOI: 10.1093/genetics/iyab084] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 06/15/2021] [Indexed: 01/07/2023] Open
Abstract
Patients with the ciliopathy Joubert syndrome present with physical anomalies, intellectual disability, and a hindbrain malformation described as the "molar tooth sign" due to its appearance on an MRI. This radiological abnormality results from a combination of hypoplasia of the cerebellar vermis and inappropriate targeting of the white matter tracts of the superior cerebellar peduncles. ARL13B is a cilia-enriched regulatory GTPase established to regulate cell fate, cell proliferation, and axon guidance through vertebrate Hedgehog signaling. In patients, mutations in ARL13B cause Joubert syndrome. To understand the etiology of the molar tooth sign, we used mouse models to investigate the role of ARL13B during cerebellar development. We found that ARL13B regulates superior cerebellar peduncle targeting and these fiber tracts require Hedgehog signaling for proper guidance. However, in mouse, the Joubert-causing R79Q mutation in ARL13B does not disrupt Hedgehog signaling nor does it impact tract targeting. We found a small cerebellar vermis in mice lacking ARL13B function but no cerebellar vermis hypoplasia in mice expressing the Joubert-causing R79Q mutation. In addition, mice expressing a cilia-excluded variant of ARL13B that transduces Hedgehog normally showed normal tract targeting and vermis width. Taken together, our data indicate that ARL13B is critical for the control of cerebellar vermis width as well as superior cerebellar peduncle axon guidance, likely via Hedgehog signaling. Thus, our work highlights the complexity of ARL13B in molar tooth sign etiology.
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Affiliation(s)
- Sarah K Suciu
- Genetics and Molecular Biology Graduate Program, Emory University, Atlanta, GA 30322, USA,Department of Human Genetics, Emory University, Atlanta, GA 30322, USA
| | - Alyssa B Long
- Department of Human Genetics, Emory University, Atlanta, GA 30322, USA
| | - Tamara Caspary
- Department of Human Genetics, Emory University, Atlanta, GA 30322, USA,Corresponding author: Department of Human Genetics, 615 Michael Street, Suite 301, Atlanta, GA 30322.
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16
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Xie N, Bai Y, Qiao L, Bai Y, Wu J, Li Y, Jiang M, Xu B, Ni Z, Yuan T, Shi Y, Wu K, Xu F, Wang J, Dong L, Liu N. ARL4C might serve as a prognostic factor and a novel therapeutic target for gastric cancer: bioinformatics analyses and biological experiments. J Cell Mol Med 2021; 25:4014-4027. [PMID: 33724652 PMCID: PMC8051716 DOI: 10.1111/jcmm.16366] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 10/24/2020] [Accepted: 01/08/2021] [Indexed: 12/19/2022] Open
Abstract
The ADP‐ribosylation factor‐like proteins (ARLs) have been proved to regulate the malignant phenotypes of several cancers. However, the exact role of ARLs in gastric cancer (GC) remains elusive. In this study, we systematically investigate the expression status, interactive relations, potential pathways, genetic variations and clinical values of ARLs in GC. We find that ARLs are significantly dysregulated in GC and involved in various cancer‐related pathways. Subsequently, machine learning models identify ARL4C as one of the two most significant clinical indicators among ARLs for GC. Furthermore, ARL4C silencing remarkably inhibits the growth and metastasis of GC cells both in vitro and in vivo. Moreover, enrichment analysis indicates that ARL4C is highly correlated with TGF‐β1 signalling. Correspondingly, TGF‐β1 treatment dramatically increases ARL4C expression and ARL4C knockdown inhibits the phosphorylation level of Smads, downstream factors of TGF‐β1. Meanwhile, the coexpression of ARL4C and TGF‐β1 worsens the prognosis of GC patients. Our work comprehensively demonstrates the crucial role of ARLs in the carcinogenesis of GC and the specific mechanisms underlying the GC‐promoting effects of TGF‐β1. More importantly, we uncover the great promise of ARL4C‐targeted therapy in improving the efficacy of TGF‐β1 inhibitors for GC patients.
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Affiliation(s)
- Ning Xie
- Department of Gastroenterology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Shaanxi Key Laboratory of Gastrointestinal Motility Disorders, Xi'an Jiaotong University, Xi'an, China
| | - Yunfan Bai
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Japan
| | - Lu Qiao
- Department of Gastroenterology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Shaanxi Key Laboratory of Gastrointestinal Motility Disorders, Xi'an Jiaotong University, Xi'an, China
| | - Yuru Bai
- Department of Gastroenterology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Shaanxi Key Laboratory of Gastrointestinal Motility Disorders, Xi'an Jiaotong University, Xi'an, China
| | - Jian Wu
- State Key Laboratory of Cancer Biology, National Clinical Research Center for Digestive Diseases and Xijing Hospital of Digestive Diseases, the Fourth Military Medical University, Xi'an, China
| | - Yan Li
- Department of Gastroenterology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Shaanxi Key Laboratory of Gastrointestinal Motility Disorders, Xi'an Jiaotong University, Xi'an, China
| | - Mingzuo Jiang
- State Key Laboratory of Cancer Biology, National Clinical Research Center for Digestive Diseases and Xijing Hospital of Digestive Diseases, the Fourth Military Medical University, Xi'an, China
| | - Bing Xu
- Department of Gastroenterology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Zhen Ni
- State Key Laboratory of Cancer Biology, National Clinical Research Center for Digestive Diseases and Xijing Hospital of Digestive Diseases, the Fourth Military Medical University, Xi'an, China
| | - Ting Yuan
- State Key Laboratory of Cancer Biology, National Clinical Research Center for Digestive Diseases and Xijing Hospital of Digestive Diseases, the Fourth Military Medical University, Xi'an, China
| | - Yongquan Shi
- State Key Laboratory of Cancer Biology, National Clinical Research Center for Digestive Diseases and Xijing Hospital of Digestive Diseases, the Fourth Military Medical University, Xi'an, China
| | - Kaichun Wu
- State Key Laboratory of Cancer Biology, National Clinical Research Center for Digestive Diseases and Xijing Hospital of Digestive Diseases, the Fourth Military Medical University, Xi'an, China
| | - Feng Xu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an, China
| | - Jinhai Wang
- Department of Gastroenterology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Shaanxi Key Laboratory of Gastrointestinal Motility Disorders, Xi'an Jiaotong University, Xi'an, China
| | - Lei Dong
- Department of Gastroenterology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Shaanxi Key Laboratory of Gastrointestinal Motility Disorders, Xi'an Jiaotong University, Xi'an, China
| | - Na Liu
- Department of Gastroenterology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Shaanxi Key Laboratory of Gastrointestinal Motility Disorders, Xi'an Jiaotong University, Xi'an, China
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17
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Partisani M, Baron CL, Ghossoub R, Fayad R, Pagnotta S, Abélanet S, Macia E, Brau F, Lacas-Gervais S, Benmerah A, Luton F, Franco M. EFA6A, an exchange factor for Arf6, regulates early steps in ciliogenesis. J Cell Sci 2021; 134:237326. [PMID: 33483367 DOI: 10.1242/jcs.249565] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 11/20/2020] [Indexed: 12/13/2022] Open
Abstract
Ciliogenesis is a coordinated process initiated by the recruitment and fusion of pre-ciliary vesicles at the distal appendages of the mother centriole through mechanisms that remain unclear. Here, we report that EFA6A (also known as PSD), an exchange factor for the small G protein Arf6, is involved in early stage of ciliogenesis by promoting the fusion of distal appendage vesicles forming the ciliary vesicle. EFA6A is present in the vicinity of the mother centriole before primary cilium assembly and prior to the arrival of Arl13B-containing vesicles. During ciliogenesis, EFA6A initially accumulates at the mother centriole and later colocalizes with Arl13B along the ciliary membrane. EFA6A depletion leads to the inhibition of ciliogenesis, the absence of centrosomal Rab8-positive structures and the accumulation of Arl13B-positive vesicles around the distal appendages. Our results uncover a novel fusion machinery, comprising EFA6A, Arf6 and Arl13B, that controls the coordinated fusion of ciliary vesicles docked at the distal appendages of the mother centriole.
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Affiliation(s)
- Mariagrazia Partisani
- Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275 CNRS-Université Côte d'Azur, 660, route des lucioles, 06560 Valbonne, France
| | - Carole L Baron
- Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275 CNRS-Université Côte d'Azur, 660, route des lucioles, 06560 Valbonne, France
| | - Rania Ghossoub
- Centre de Recherche en Cancérologie de Marseille (CRCM), Inserm, U1068-CNRS UMR7258, Aix-Marseille Université, Institut Paoli-Calmettes, 13009 Marseille, France
| | - Racha Fayad
- Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275 CNRS-Université Côte d'Azur, 660, route des lucioles, 06560 Valbonne, France
| | - Sophie Pagnotta
- Centre Commun de Microscopie Appliquée (CCMA), Université Côte d'Azur Parc Valrose, 06103 Nice cedex 2, France
| | - Sophie Abélanet
- Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275 CNRS-Université Côte d'Azur, 660, route des lucioles, 06560 Valbonne, France
| | - Eric Macia
- Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275 CNRS-Université Côte d'Azur, 660, route des lucioles, 06560 Valbonne, France
| | - Frédéric Brau
- Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275 CNRS-Université Côte d'Azur, 660, route des lucioles, 06560 Valbonne, France
| | - Sandra Lacas-Gervais
- Centre Commun de Microscopie Appliquée (CCMA), Université Côte d'Azur Parc Valrose, 06103 Nice cedex 2, France
| | - Alexandre Benmerah
- Université de Paris, Imagine Institute, Laboratory of Inherited Kidney Diseases, INSERM UMR 1163, F-75015, Paris, France
| | - Frédéric Luton
- Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275 CNRS-Université Côte d'Azur, 660, route des lucioles, 06560 Valbonne, France
| | - Michel Franco
- Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275 CNRS-Université Côte d'Azur, 660, route des lucioles, 06560 Valbonne, France
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18
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Hanna RM, Streja E, Kalantar-Zadeh K. Burden of Anemia in Chronic Kidney Disease: Beyond Erythropoietin. Adv Ther 2021; 38:52-75. [PMID: 33123967 PMCID: PMC7854472 DOI: 10.1007/s12325-020-01524-6] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 10/03/2020] [Indexed: 02/08/2023]
Abstract
Anemia is a frequent comorbidity of chronic kidney disease (CKD) and is associated with a considerable burden because of decreased patient health-related quality of life and increased healthcare resource utilization. Based on observational data, anemia is associated with an increased risk of CKD progression, cardiovascular events, and all-cause mortality. The current standard of care includes oral or intravenous iron supplementation, erythropoiesis-stimulating agents, and red blood cell transfusion. However, each of these therapies has its own set of population-specific patient concerns, including increased risk of cardiovascular disease, thrombosis, and mortality. Patients receiving dialysis or those who have concurrent diabetes or high blood pressure may be at greater risk of developing these complications. In particular, treatment with high doses of erythropoiesis-stimulating agents has been associated with increased rates of hospitalization, cardiovascular events, and mortality. Resistance to erythropoiesis-stimulating agents remains a therapeutic challenge in a subset of patients. Hypoxia-inducible factor transcription factors, which regulate several genes involved in erythropoiesis and iron metabolism, can be stabilized by a new class of drugs that act as inhibitors of hypoxia-inducible factor prolyl-hydroxylase enzymes to promote erythropoiesis and elevate hemoglobin levels. Here, we review the burden of anemia of chronic kidney disease, the shortcomings of current standard of care, and the potential practical advantages of hypoxia-inducible factor prolyl-hydroxylase inhibitors in the treatment of patients with anemia of CKD.
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Affiliation(s)
- Ramy M Hanna
- Division of Nephrology, Hypertension and Kidney Transplantation, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California, Irvine School of Medicine, Orange, CA, USA
| | - Elani Streja
- Division of Nephrology and Hypertension, University of California, Irvine School of Medicine, Orange, CA, USA
| | - Kamyar Kalantar-Zadeh
- Division of Nephrology and Hypertension, University of California, Irvine School of Medicine, Orange, CA, USA.
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19
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Streets AJ, Prosseda PP, Ong AC. Polycystin-1 regulates ARHGAP35-dependent centrosomal RhoA activation and ROCK signaling. JCI Insight 2020; 5:135385. [PMID: 32663194 PMCID: PMC7455122 DOI: 10.1172/jci.insight.135385] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 07/08/2020] [Indexed: 11/17/2022] Open
Abstract
Mutations in PKD1 (encoding for polycystin-1 [PC1]) are found in 80%–85% of patients with autosomal dominant polycystic kidney disease (ADPKD). We tested the hypothesis that changes in actin dynamics result from PKD1 mutations through dysregulation of compartmentalized centrosomal RhoA signaling mediated by specific RhoGAP (ARHGAP) proteins resulting in the complex cellular cystic phenotype. Initial studies revealed that the actin cytoskeleton was highly disorganized in cystic cells derived from patients with PKD1 and was associated with an increase in total and centrosomal active RhoA and ROCK signaling. Using cilia length as a phenotypic readout for centrosomal RhoA activity, we identified ARHGAP5, -29, and -35 as essential regulators of ciliation in normal human renal tubular cells. Importantly, a specific decrease in centrosomal ARHGAP35 was observed in PKD1-null cells using a centrosome-targeted proximity ligation assay and by dual immunofluorescence labeling. Finally, the ROCK inhibitor hydroxyfasudil reduced cyst expansion in both human PKD1 3D cyst assays and an inducible Pkd1 mouse model. In summary, we report a potentially novel interaction between PC1 and ARHGAP35 in the regulation of centrosomal RhoA activation and ROCK signaling. Targeting the RhoA/ROCK pathway inhibited cyst formation in vitro and in vivo, indicating its relevance to ADPKD pathogenesis and for developing new therapies to inhibit cyst initiation. Polycystin-1, the major protein mutated in autosomal dominant polycystic kidney disease, activates centrosomal RhoA activity via interaction with the Rho-GAP protein ARHGAP35, resulting in shorter cilia.
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20
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Cilia and polycystic kidney disease. Semin Cell Dev Biol 2020; 110:139-148. [PMID: 32475690 DOI: 10.1016/j.semcdb.2020.05.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 05/03/2020] [Accepted: 05/03/2020] [Indexed: 11/20/2022]
Abstract
Polycystic kidney disease (PKD), comprising autosomal dominant polycystic kidney disease (ADPKD) and autosomal recessive polycystic kidney disease (ARPKD), is characterized by incessant cyst formation in the kidney and liver. ADPKD and ARPKD represent the leading genetic causes of renal disease in adults and children, respectively. ADPKD is caused by mutations in PKD1 encoding polycystin1 (PC1) and PKD2 encoding polycystin 2 (PC2). PC1/2 are multi-pass transmembrane proteins that form a complex localized in the primary cilium. Predominant ARPKD cases are caused by mutations in polycystic kidney and hepatic disease 1 (PKHD1) gene that encodes the Fibrocystin/Polyductin (FPC) protein, whereas a small subset of cases are caused by mutations in DAZ interacting zinc finger protein 1 like (DZIP1L) gene. FPC is a type I transmembrane protein, localizing to the cilium and basal body, in addition to other compartments, and DZIP1L encodes a transition zone/basal body protein. Apparently, PC1/2 and FPC are signaling molecules, while the mechanism that cilia employ to govern renal tubule morphology and prevent cyst formation is unclear. Nonetheless, recent genetic and biochemical studies offer a glimpse of putative physiological malfunctions and the pathomechanisms underlying both disease entities. In this review, I summarize the results of genetic studies that deduced the function of PC1/2 on cilia and of cilia themselves in cyst formation in ADPKD, and I discuss studies regarding regulation of polycystin biogenesis and cilia trafficking. I also summarize the synergistic genetic interactions between Pkd1 and Pkhd1, and the unique tissue patterning event controlled by FPC, but not PC1. Interestingly, while DZIP1L mutations generate compromised PC1/2 cilia expression, FPC deficiency does not affect PC1/2 biogenesis and ciliary localization, indicating that divergent mechanisms could lead to cyst formation in ARPKD. I conclude by outlining promising areas for future PKD research and highlight rationales for potential therapeutic interventions for PKD treatment.
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21
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Chien HJ, Xue YT, Chen HC, Wu KY, Lai CC. Proteomic analysis of rat kidney under maleic acid treatment by SWATH-MS technology. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2020; 34 Suppl 1:e8633. [PMID: 31677360 DOI: 10.1002/rcm.8633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 10/03/2019] [Accepted: 10/09/2019] [Indexed: 06/10/2023]
Abstract
RATIONALE Maleic acid is an industrial-grade chemical that is often used in adhesives, stabilizers, and preservatives. It is unknown whether long-term consumption of maleic acid modified starch is harmful to humans. However, many studies have indicated that maleic acid causes renal tubular damage in animal models, even as the associated pathways remain unclear. Sequential window acquisition of all theoretical fragment ion spectra (SWATH) is the most innovative of the label-free quantitative technologies which have better quantification performance. Therefore, SWATH technology was used to investigate the effect of maleic acid on the rat kidney proteome in this study. METHODS Sprague-Dawley(SD) rats were treated with 0 mg/kg (control), 6 mg/kg (low-dose), 10 mg/kg (medium-dose), and 60 mg/kg (high-dose) of maleic acid. After kidney protein extraction, 28% SDS-PAGE was used, followed by in-gel digestion and desalting. Next, the samples were analyzed with ultra-performance liquid chromatography (UPLC) coupled with quadrupole time-of-flight mass spectrometry (Q-TOF MS), and data-dependent acquisition (DDA) and SWATH technology were also used. The gene ontology and pathway analysis were accomplished. Ultimately, these protein biomarkers were validated by using scheduled high-resolution multiple reaction monitoring (sMRMHR ). RESULTS Comparisons of the control group with the other three groups revealed that 95, 130, and 103 proteins were expressed at significantly different levels in the control group and in the low-dose, medium-dose, and high-dose groups, respectively. According to the gene ontology analysis, the major processes that these proteins were involved in were metabolic processes, biological regulation, cellular processes, and responses to stimuli; the major functions that these proteins were involved in were binding, hydrolase activity, catalytic activity, and oxidoreductase activity; and the major cellular components hat they were involved in were the cytoplasm, extracellular region, membrane, and mitochondria. According to the KEGG pathway analysis, these proteins were involved in 35 pathways, five of which, the carbohydrate metabolism, folate biosynthesis, renal tubular resorption, amino acid metabolism, and Ras signaling pathways, are discussed in this study. Ultimately, 19 proteins involved in 12 important pathways were validated by sMRMHR . CONCLUSIONS It was demonstrated that maleic acid caused insufficient energy production, which might lead to a decrease in the activity of the sodium-potassium ATP pump and hydrogen ion ATP pump, which could in turn have caused renal tubular resorption and hydrogen ion regulation to be blocked, thus leading to the accumulation of hydrogen ions in the renal tubules, which would then result in renal tubular acidification followed finally by Fanconi syndrome.
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Affiliation(s)
- Han-Ju Chien
- Institute of Molecular Biology, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Yu-Ting Xue
- Institute of Molecular Biology, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Hsin-Chang Chen
- Institute of Occupational Medicine and Industrial Hygiene, College of Public Health, National Taiwan University, No. 17, ShiuJou Road, Taipei, 10055, Taiwan
| | - Kuen-Yuh Wu
- Institute of Occupational Medicine and Industrial Hygiene, College of Public Health, National Taiwan University, No. 17, ShiuJou Road, Taipei, 10055, Taiwan
| | - Chien-Chen Lai
- Institute of Molecular Biology, National Chung Hsing University, Taichung, 40227, Taiwan
- Graduate Institute of Chinese Medical Science, China Medical University, Taichung, 40447, Taiwan
- Advanced Plant Biotechnology Center, National Chung Hsing University, Taichung, 40402, Taiwan
- Department of Pharmacology, National Defense Medical Center, Taipei City, 11490, Taiwan
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22
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Kuhns S, Seixas C, Pestana S, Tavares B, Nogueira R, Jacinto R, Ramalho JS, Simpson JC, Andersen JS, Echard A, Lopes SS, Barral DC, Blacque OE. Rab35 controls cilium length, function and membrane composition. EMBO Rep 2019; 20:e47625. [PMID: 31432619 PMCID: PMC6776896 DOI: 10.15252/embr.201847625] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 07/23/2019] [Accepted: 07/31/2019] [Indexed: 12/12/2022] Open
Abstract
Rab and Arl guanine nucleotide-binding (G) proteins regulate trafficking pathways essential for the formation, function and composition of primary cilia, which are sensory devices associated with Sonic hedgehog (Shh) signalling and ciliopathies. Here, using mammalian cells and zebrafish, we uncover ciliary functions for Rab35, a multitasking G protein with endocytic recycling, actin remodelling and cytokinesis roles. Rab35 loss via siRNAs, morpholinos or knockout reduces cilium length in mammalian cells and the zebrafish left-right organiser (Kupffer's vesicle) and causes motile cilia-associated left-right asymmetry defects. Consistent with these observations, GFP-Rab35 localises to cilia, as do GEF (DENND1B) and GAP (TBC1D10A) Rab35 regulators, which also regulate ciliary length and Rab35 ciliary localisation. Mammalian Rab35 also controls the ciliary membrane levels of Shh signalling regulators, promoting ciliary targeting of Smoothened, limiting ciliary accumulation of Arl13b and the inositol polyphosphate 5-phosphatase (INPP5E). Rab35 additionally regulates ciliary PI(4,5)P2 levels and interacts with Arl13b. Together, our findings demonstrate roles for Rab35 in regulating cilium length, function and membrane composition and implicate Rab35 in pathways controlling the ciliary levels of Shh signal regulators.
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Affiliation(s)
- Stefanie Kuhns
- School of Biomolecular and Biomedical ScienceUniversity College DublinDublin 4Ireland
- Department of Biochemistry and Molecular BiologyUniversity of Southern DenmarkOdense MDenmark
| | - Cecília Seixas
- CEDOCNOVA Medical School|Faculdade de Ciências MédicasUniversidade NOVA de LisboaLisboaPortugal
| | - Sara Pestana
- CEDOCNOVA Medical School|Faculdade de Ciências MédicasUniversidade NOVA de LisboaLisboaPortugal
| | - Bárbara Tavares
- CEDOCNOVA Medical School|Faculdade de Ciências MédicasUniversidade NOVA de LisboaLisboaPortugal
| | - Renata Nogueira
- CEDOCNOVA Medical School|Faculdade de Ciências MédicasUniversidade NOVA de LisboaLisboaPortugal
| | - Raquel Jacinto
- CEDOCNOVA Medical School|Faculdade de Ciências MédicasUniversidade NOVA de LisboaLisboaPortugal
| | - José S Ramalho
- CEDOCNOVA Medical School|Faculdade de Ciências MédicasUniversidade NOVA de LisboaLisboaPortugal
| | - Jeremy C Simpson
- School of Biology and Environmental ScienceUniversity College DublinDublin 4Ireland
| | - Jens S Andersen
- Department of Biochemistry and Molecular BiologyUniversity of Southern DenmarkOdense MDenmark
| | | | - Susana S Lopes
- CEDOCNOVA Medical School|Faculdade de Ciências MédicasUniversidade NOVA de LisboaLisboaPortugal
| | - Duarte C Barral
- CEDOCNOVA Medical School|Faculdade de Ciências MédicasUniversidade NOVA de LisboaLisboaPortugal
| | - Oliver E Blacque
- School of Biomolecular and Biomedical ScienceUniversity College DublinDublin 4Ireland
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Sztul E, Chen PW, Casanova JE, Cherfils J, Dacks JB, Lambright DG, Lee FJS, Randazzo PA, Santy LC, Schürmann A, Wilhelmi I, Yohe ME, Kahn RA. ARF GTPases and their GEFs and GAPs: concepts and challenges. Mol Biol Cell 2019; 30:1249-1271. [PMID: 31084567 PMCID: PMC6724607 DOI: 10.1091/mbc.e18-12-0820] [Citation(s) in RCA: 156] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 02/26/2019] [Accepted: 03/11/2019] [Indexed: 12/12/2022] Open
Abstract
Detailed structural, biochemical, cell biological, and genetic studies of any gene/protein are required to develop models of its actions in cells. Studying a protein family in the aggregate yields additional information, as one can include analyses of their coevolution, acquisition or loss of functionalities, structural pliability, and the emergence of shared or variations in molecular mechanisms. An even richer understanding of cell biology can be achieved through evaluating functionally linked protein families. In this review, we summarize current knowledge of three protein families: the ARF GTPases, the guanine nucleotide exchange factors (ARF GEFs) that activate them, and the GTPase-activating proteins (ARF GAPs) that have the ability to both propagate and terminate signaling. However, despite decades of scrutiny, our understanding of how these essential proteins function in cells remains fragmentary. We believe that the inherent complexity of ARF signaling and its regulation by GEFs and GAPs will require the concerted effort of many laboratories working together, ideally within a consortium to optimally pool information and resources. The collaborative study of these three functionally connected families (≥70 mammalian genes) will yield transformative insights into regulation of cell signaling.
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Affiliation(s)
- Elizabeth Sztul
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Pei-Wen Chen
- Department of Biology, Williams College, Williamstown, MA 01267
| | - James E. Casanova
- Department of Cell Biology, University of Virginia, Charlottesville, VA 22908
| | - Jacqueline Cherfils
- Laboratoire de Biologie et Pharmacologie Appliquée, CNRS and Ecole Normale Supérieure Paris-Saclay, 94235 Cachan, France
| | - Joel B. Dacks
- Division of Infectious Disease, Department of Medicine, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - David G. Lambright
- Program in Molecular Medicine and Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Amherst, MA 01605
| | - Fang-Jen S. Lee
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | | | - Lorraine C. Santy
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA 16802
| | - Annette Schürmann
- German Institute of Human Nutrition, 85764 Potsdam-Rehbrücke, Germany
| | - Ilka Wilhelmi
- German Institute of Human Nutrition, 85764 Potsdam-Rehbrücke, Germany
| | - Marielle E. Yohe
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| | - Richard A. Kahn
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322-3050
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24
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Legué E, Liem KF. Tulp3 Is a Ciliary Trafficking Gene that Regulates Polycystic Kidney Disease. Curr Biol 2019; 29:803-812.e5. [PMID: 30799240 DOI: 10.1016/j.cub.2019.01.054] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 11/12/2018] [Accepted: 01/21/2019] [Indexed: 12/17/2022]
Abstract
The primary cilium is an organelle essential for cell signaling pathways. One of the most common human genetic diseases is autosomal dominant polycystic kidney disease (ADPKD), which is caused by mutations in the PKD1 or PKD2 genes that encode Polycystin 1 and 2 (PC1/2), transmembrane proteins that translocate to the cilium. Mutations in genes that disrupt ciliogenesis also cause kidney cysts as part of a "ciliopathic" disease spectrum. The molecular mechanisms that link cilia function with renal cystic diseases are not well understood, and the mechanistic relationship between ADPKD and ciliopathic PKD is not known. Here we identify the gene Tubby-like protein-3 (Tulp3) as a key regulator of renal cystic disease from a forward genetic screen in the mouse. Mice homozygous for a hypomorphic missense mutation within the conserved Tubby domain of Tulp3 develop cysts at late embryonic stages, leading to severe postnatal loss of kidney function. In contrast to other ciliopathic disease models, Tulp3 mutations do not affect ciliogenesis. Instead, we demonstrate that Tulp3 is essential for the trafficking of the Joubert syndrome-associated small GTPase Arl13b into kidney cilia. We show that reduction of Pkd1 dosage promotes cystogenesis in the Tulp3 conditional ciliopathic PKD model. However, in an adult model of ADPKD utilizing inducible conditional Pkd1 deletion, concomitant removal of Tulp3 surprisingly ameliorates cystic disease. Therefore, Tulp3 controls distinct ciliary pathways that positively or negatively regulate cystogenesis depending on the cellular context.
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Affiliation(s)
- Emilie Legué
- Vertebrate Developmental Biology Program, Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| | - Karel F Liem
- Vertebrate Developmental Biology Program, Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
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25
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Hwang SH, Somatilaka BN, Badgandi H, Palicharla VR, Walker R, Shelton JM, Qian F, Mukhopadhyay S. Tulp3 Regulates Renal Cystogenesis by Trafficking of Cystoproteins to Cilia. Curr Biol 2019; 29:790-802.e5. [PMID: 30799239 DOI: 10.1016/j.cub.2019.01.047] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 11/09/2018] [Accepted: 01/17/2019] [Indexed: 12/25/2022]
Abstract
Polycystic kidney disease proteins, polycystin-1 and polycystin-2, localize to primary cilia. Polycystin knockouts have severe cystogenesis compared to ciliary disruption, whereas simultaneous ciliary loss suppresses excessive cyst growth. These data suggest the presence of a cystogenic activator that is inhibited by polycystins and an independent but relatively minor cystogenic inhibitor, either of which are cilia dependent. However, current genetic models targeting cilia completely ablate the compartment, making it difficult to uncouple cystoprotein function from ciliary localization. Thus, the role of cilium-generated signaling in cystogenesis is unclear. We recently demonstrated that the tubby family protein Tulp3 determines ciliary trafficking of polycystins in kidney collecting duct cells without affecting protein levels or cilia. Here, we demonstrate that embryonic-stage, nephron-specific Tulp3 knockout mice developed cystic kidneys, while retaining intact cilia. Cystic kidneys showed increased mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK), mTOR, and persistently high cyclic AMP (cAMP) signaling, suggesting contribution of multiple factors to cystogenesis. Based on kidney-to-body-weight ratio, cystic index, and epithelial proliferation in developing tubules or cysts, the severity of cystogenesis upon Tulp3 deletion was intermediate between that caused by loss of polycystin-1 or cilia. However, concomitant Tulp3 loss did not inhibit cystogenesis in polycystin-1 knockouts, unlike ciliary disruption. Interestingly, ciliary trafficking of the small guanosine triphosphatase (GTPase) Arl13b, loss of which causes cystogenic severity similar to ciliary loss, was reduced prior to cyst initiation. Thus, we propose that cystogenesis in Tulp3 mutants results from a reduction of ciliary levels of polycystins, Arl13b, and Arl13b-dependent lipidated cargoes. Arl13b might be the ciliary factor that represses cystogenesis distinct from polycystins.
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Affiliation(s)
- Sun-Hee Hwang
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Bandarigoda N Somatilaka
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Hemant Badgandi
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Vivek Reddy Palicharla
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Rebecca Walker
- Division of Nephrology, University of Maryland School of Medicine, 655 West Baltimore Street, Baltimore, MD 21201, USA
| | - John M Shelton
- Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Feng Qian
- Division of Nephrology, University of Maryland School of Medicine, 655 West Baltimore Street, Baltimore, MD 21201, USA
| | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
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26
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Dilan TL, Moye AR, Salido EM, Saravanan T, Kolandaivelu S, Goldberg AFX, Ramamurthy V. ARL13B, a Joubert Syndrome-Associated Protein, Is Critical for Retinogenesis and Elaboration of Mouse Photoreceptor Outer Segments. J Neurosci 2019; 39:1347-1364. [PMID: 30573647 PMCID: PMC6381253 DOI: 10.1523/jneurosci.1761-18.2018] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 11/16/2018] [Accepted: 12/12/2018] [Indexed: 11/21/2022] Open
Abstract
Mutations in the Joubert syndrome-associated small GTPase ARL13B are linked to photoreceptor impairment and vision loss. To determine the role of ARL13B in the development, function, and maintenance of ciliated photoreceptors, we generated a pan-retina knock-out (Six3-Cre) and a rod photoreceptor-specific inducible conditional knock-out (Pde6g-CreERT2) of ARL13B using murine models. Embryonic deletion of ARL13B led to defects in retinal development with reduced cell proliferation. In the absence of ARL13B, photoreceptors failed to develop outer segment (OS) membranous discs and axonemes, resulting in loss of function and rapid degeneration. Additionally, the majority of photoreceptor basal bodies did not dock properly at the apical edge of the inner segments. The removal of ARL13B in adult rod photoreceptor cells after maturation of OS resulted in loss of photoresponse and vesiculation in the OS. Before changes in photoresponse, removal of ARL13B led to mislocalization of rhodopsin, prenylated phosphodiesterase-6 (PDE6), and intraflagellar transport protein-88 (IFT88). Our findings show that ARL13B is required at multiple stages of retinogenesis, including early postnatal proliferation of retinal progenitor cells, development of photoreceptor cilia, and morphogenesis of photoreceptor OS discs regardless of sex. Last, our results establish a need for ARL13B in photoreceptor maintenance and protein trafficking.SIGNIFICANCE STATEMENT The normal development of photoreceptor cilia is essential to create functional, organized outer segments with stacked membrane discs that house the phototransduction proteins necessary for sight. Our study identifies a complex role for ARL13B, a small GTPase linked to Joubert syndrome and visual impairment, at various stages of photoreceptor development. Loss of ARL13B led to defects in retinal proliferation, altered placement of basal bodies crucial for components of the cilium (transition zone) to emanate, and absence of photoreceptor-stacked discs. These defects led to extinguished visual response and dysregulated protein trafficking. Our findings show the complex role ARL13B plays in photoreceptor development, viability, and function. Our study accounts for the severe retinal impairment observed in ARL13B-linked Joubert syndrome patients.
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Affiliation(s)
- Tanya L Dilan
- Department of Ophthalmology and Neuroscience
- Department of Biochemistry
| | - Abigail R Moye
- Department of Ophthalmology and Neuroscience
- Department of Biochemistry
| | | | | | | | | | - Visvanathan Ramamurthy
- Department of Ophthalmology and Neuroscience,
- Department of Biochemistry
- WVU Rockefeller Neuroscience Institute, West Virginia University, Morgantown, West Virginia 26506, and
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27
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Baehr W, Hanke-Gogokhia C, Sharif A, Reed M, Dahl T, Frederick JM, Ying G. Insights into photoreceptor ciliogenesis revealed by animal models. Prog Retin Eye Res 2018; 71:26-56. [PMID: 30590118 DOI: 10.1016/j.preteyeres.2018.12.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 12/10/2018] [Accepted: 12/18/2018] [Indexed: 12/11/2022]
Abstract
Photoreceptors are polarized neurons, with very specific subcellular compartmentalization and unique requirements for protein expression and trafficking. Each photoreceptor contains an outer segment, the site of photon capture that initiates vision, an inner segment that houses the biosynthetic machinery and a synaptic terminal for signal transmission to downstream neurons. Outer segments and inner segments are connected by a connecting cilium (CC), the equivalent of a transition zone (TZ) of primary cilia. The connecting cilium is part of the basal body/axoneme backbone that stabilizes the outer segment. This report will update the reader on late developments in photoreceptor ciliogenesis and transition zone formation, specifically in mouse photoreceptors, focusing on early events in photoreceptor ciliogenesis. The connecting cilium, an elongated and narrow structure through which all outer segment proteins and membrane components must traffic, functions as a gate that controls access to the outer segment. Here we will review genes and their protein products essential for basal body maturation and for CC/TZ genesis, sorted by phenotype. Emphasis is given to naturally occurring mouse mutants and gene knockouts that interfere with CC/TZ formation and ciliogenesis.
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Affiliation(s)
- Wolfgang Baehr
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA.
| | - Christin Hanke-Gogokhia
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Ali Sharif
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Michelle Reed
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Tiffanie Dahl
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Jeanne M Frederick
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Guoxin Ying
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
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28
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Silva LM, Jacobs DT, Allard BA, Fields TA, Sharma M, Wallace DP, Tran PV. Inhibition of Hedgehog signaling suppresses proliferation and microcyst formation of human Autosomal Dominant Polycystic Kidney Disease cells. Sci Rep 2018; 8:4985. [PMID: 29563577 PMCID: PMC5862907 DOI: 10.1038/s41598-018-23341-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 03/09/2018] [Indexed: 12/13/2022] Open
Abstract
Autosomal Dominant Polycystic Kidney Disease (ADPKD) is caused by mutation of PKD1 or PKD2, which encode polycystin 1 and 2, respectively. The polycystins localize to primary cilia and the functional loss of the polycystin complex leads to the formation and progressive growth of fluid-filled cysts in the kidney. The pathogenesis of ADPKD is complex and molecular mechanisms connecting ciliary dysfunction to renal cystogenesis are unclear. Primary cilia mediate Hedgehog signaling, which modulates cell proliferation and differentiation in a tissue-dependent manner. Previously, we showed that Hedgehog signaling was increased in cystic kidneys of several PKD mouse models and that Hedgehog inhibition prevented cyst formation in embryonic PKD mouse kidneys treated with cAMP. Here, we show that in human ADPKD tissue, Hedgehog target and activator, Glioma 1, was elevated and localized to cyst-lining epithelial cells and to interstitial cells, suggesting increased autocrine and paracrine Hedgehog signaling in ADPKD, respectively. Further, Hedgehog inhibitors reduced basal and cAMP-induced proliferation of ADPKD cells and cyst formation in vitro. These data suggest that Hedgehog signaling is increased in human ADPKD and that suppression of Hedgehog signaling can counter cellular processes that promote cyst growth in vitro.
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Affiliation(s)
- Luciane M Silva
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS, USA.,Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Damon T Jacobs
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS, USA.,Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Bailey A Allard
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS, USA.,Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Timothy A Fields
- Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS, USA.,Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Madhulika Sharma
- Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS, USA.,Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Darren P Wallace
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA.,Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS, USA.,Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Pamela V Tran
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS, USA. .,Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA.
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29
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Bay SN, Long AB, Caspary T. Disruption of the ciliary GTPase Arl13b suppresses Sonic hedgehog overactivation and inhibits medulloblastoma formation. Proc Natl Acad Sci U S A 2018; 115:1570-1575. [PMID: 29378965 PMCID: PMC5816136 DOI: 10.1073/pnas.1706977115] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Medulloblastoma (MB) is the most common malignant pediatric brain tumor, and overactivation of the Sonic Hedgehog (Shh) signaling pathway, which requires the primary cilium, causes 30% of MBs. Current treatments have known negative side effects or resistance mechanisms, so new treatments are necessary. Shh signaling mutations, like those that remove Patched1 (Ptch1) or activate Smoothened (Smo), cause tumors dependent on the presence of cilia. Genetic ablation of cilia prevents these tumors by removing Gli activator, but cilia are a poor therapeutic target since they support many biological processes. A more appropriate strategy would be to identify a protein that functionally disentangles Gli activation and ciliogenesis. Our mechanistic understanding of the ciliary GTPase Arl13b predicts that it could be such a target. Arl13b mutants retain short cilia, and loss of Arl13b results in ligand-independent, constitutive, low-level pathway activation but prevents maximal signaling without disrupting Gli repressor. Here, we show that deletion of Arl13b reduced Shh signaling levels in the presence of oncogenic SmoA1, suggesting Arl13b acts downstream of known tumor resistance mechanisms. Knockdown of ARL13B in human MB cell lines and in primary mouse MB cell culture decreased proliferation. Importantly, loss of Arl13b in a Ptch1-deleted mouse model of MB inhibited tumor formation. Postnatal depletion of Arl13b does not lead to any overt phenotypes in the epidermis, liver, or cerebellum. Thus, our in vivo and in vitro studies demonstrate that disruption of Arl13b inhibits cilia-dependent oncogenic Shh overactivation.
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Affiliation(s)
- Sarah N Bay
- Department of Human Genetics, Emory University, Atlanta, GA 30322
- Genetics and Molecular Biology Program, Emory University, Atlanta, GA 30322
| | - Alyssa B Long
- Department of Human Genetics, Emory University, Atlanta, GA 30322
| | - Tamara Caspary
- Department of Human Genetics, Emory University, Atlanta, GA 30322;
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Deficiency of primary cilia in kidney epithelial cells induces epithelial to mesenchymal transition. Biochem Biophys Res Commun 2018; 496:450-454. [DOI: 10.1016/j.bbrc.2018.01.079] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 01/11/2018] [Indexed: 01/15/2023]
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Hanke-Gogokhia C, Wu Z, Sharif A, Yazigi H, Frederick JM, Baehr W. The guanine nucleotide exchange factor Arf-like protein 13b is essential for assembly of the mouse photoreceptor transition zone and outer segment. J Biol Chem 2017; 292:21442-21456. [PMID: 29089384 DOI: 10.1074/jbc.ra117.000141] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Revised: 10/24/2017] [Indexed: 01/17/2023] Open
Abstract
Arf-like protein 13b (ARL13b) is a small GTPase that functions as a guanosine nucleotide exchange factor (GEF) for ARL3-GDP. ARL13b is located exclusively in photoreceptor outer segments (OS) presumably anchored to discs by palmitoylation, whereas ARL3 is an inner segment cytoplasmic protein. Hypomorphic mutations affecting the ARL13b G-domain inactivate GEF activity and lead to Joubert syndrome (JS) in humans. However, the molecular mechanisms in ARL13b mutation-induced Joubert syndrome, particularly the function of primary cilia, are still incompletely understood. Because Arl13b germline knockouts in mouse are lethal, we generated retina-specific deletions of ARL13b in which ARL3-GTP formation is impaired. In mouse retArl13b-/- central retina at postnatal day 6 (P6) and older, outer segments were absent, thereby preventing trafficking of outer segment proteins to their destination. Ultrastructure of postnatal day 10 (P10) central retArl13b-/- photoreceptors revealed docking of basal bodies to cell membranes, but mature transition zones and disc structures were absent. Deletion of ARL13b in adult mice via tamoxifen-induced Cre/loxP recombination indicated that axonemes gradually shorten and outer segments progressively degenerate. IFT88, essential for anterograde intraflagellar transport (IFT), was significantly reduced at tamArl13b-/- basal bodies, suggesting impairment of intraflagellar transport. AAV2/8 vector-mediated ARL13b expression in the retArl13b-/- retina rescued ciliogenesis.
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Affiliation(s)
- Christin Hanke-Gogokhia
- From the Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Science Center, Salt Lake City, Utah 84132
| | - Zhijian Wu
- NEI, National Institutes of Health, Bethesda, Maryland 20892
| | - Ali Sharif
- From the Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Science Center, Salt Lake City, Utah 84132
| | - Hussein Yazigi
- From the Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Science Center, Salt Lake City, Utah 84132
| | - Jeanne M Frederick
- From the Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Science Center, Salt Lake City, Utah 84132
| | - Wolfgang Baehr
- From the Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Science Center, Salt Lake City, Utah 84132, .,Department of Neurobiology and Anatomy, University of Utah Health Science Center, Salt Lake City, Utah 84132, and.,Department of Biology, University of Utah, Salt Lake City, Utah 84112
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Roy K, Jerman S, Jozsef L, McNamara T, Onyekaba G, Sun Z, Marin EP. Palmitoylation of the ciliary GTPase ARL13b is necessary for its stability and its role in cilia formation. J Biol Chem 2017; 292:17703-17717. [PMID: 28848045 PMCID: PMC5663873 DOI: 10.1074/jbc.m117.792937] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Revised: 08/18/2017] [Indexed: 01/01/2023] Open
Abstract
Primary cilia are hairlike extensions of the plasma membrane of most mammalian cells that serve specialized signaling functions. To traffic properly to cilia, multiple cilia proteins rely on palmitoylation, the post-translational attachment of a saturated 16-carbon lipid. However, details regarding the mechanism of how palmitoylation affects cilia protein localization and function are unknown. Herein, we investigated the protein ADP-ribosylation factor-like GTPase 13b (ARL13b) as a model palmitoylated ciliary protein. Using biochemical, cellular, and in vivo studies, we found that ARL13b palmitoylation occurs in vivo in mouse kidneys and that it is required for trafficking to and function within cilia. Myristoylation, a 14-carbon lipid, is shown to largely substitute for palmitoylation with regard to cilia localization of ARL13b, but not with regard to its function within cilia. The functional importance of palmitoylation results in part from a dramatic increase in ARL13b stability, which is not observed with myristoylation. Additional results show that blockade of depalmitoylation slows the degradation of ARL13b that occurs during cilia resorption, raising the possibility that the sensitivity of ARL13b stability to palmitoylation may be exploited by the cell to accelerate degradation of ARL13b by depalmitoylating it. Together, the results show that palmitoylation plays a unique and critical role in controlling the localization, stability, abundance, and thus function of ARL13b. Pharmacological manipulation of protein palmitoylation may be a strategy to alter cilia function.
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Affiliation(s)
- Kasturi Roy
- From the Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine, New Haven, Connecticut 06520-8029 and
| | - Stephanie Jerman
- the Department of Genetics, Yale University School of Medicine, New Haven, Connecticut 06520-8029
| | - Levente Jozsef
- From the Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine, New Haven, Connecticut 06520-8029 and
| | - Thomas McNamara
- From the Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine, New Haven, Connecticut 06520-8029 and
| | - Ginikanwa Onyekaba
- From the Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine, New Haven, Connecticut 06520-8029 and
| | - Zhaoxia Sun
- the Department of Genetics, Yale University School of Medicine, New Haven, Connecticut 06520-8029
| | - Ethan P Marin
- From the Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine, New Haven, Connecticut 06520-8029 and
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Ye H, Wang X, Constans MM, Sussman CR, Chebib FT, Irazabal MV, Young WF, Harris PC, Kirschner LS, Torres VE. The regulatory 1α subunit of protein kinase A modulates renal cystogenesis. Am J Physiol Renal Physiol 2017; 313:F677-F686. [PMID: 28615245 DOI: 10.1152/ajprenal.00119.2017] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 06/09/2017] [Accepted: 06/12/2017] [Indexed: 11/22/2022] Open
Abstract
The failure of the polycystins (PCs) to function in primary cilia is thought to be responsible for autosomal dominant polycystic kidney disease (ADPKD). Primary cilia integrate multiple cellular signaling pathways, including calcium, cAMP, Wnt, and Hedgehog, which control cell proliferation and differentiation. It has been proposed that mutated PCs result in reduced intracellular calcium, which in turn upregulates cAMP, protein kinase A (PKA) signaling, and subsequently other proliferative signaling pathways. However, the role of PKA in ADPKD has not been directly ascertained in vivo, although the expression of the main regulatory subunit of PKA in cilia and other compartments (PKA-RIα, encoded by PRKAR1A) is increased in a mouse model orthologous to ADPKD. Therefore, we generated a kidney-specific knockout of Prkar1a to examine the consequences of constitutive upregulation of PKA on wild-type and Pkd1 hypomorphic (Pkd1RC) backgrounds. Kidney-specific loss of Prkar1a induced renal cystic disease and markedly aggravated cystogenesis in the Pkd1RC models. In both settings, it was accompanied by upregulation of Src, Ras, MAPK/ERK, mTOR, CREB, STAT3, Pax2 and Wnt signaling. On the other hand, Gli3 repressor activity was enhanced, possibly contributing to hydronephrosis and impaired glomerulogenesis in some animals. To assess the relevance of these observations in humans we looked for and found evidence for kidney and liver cystic phenotypes in the Carney complex, a tumoral syndrome caused by mutations in PRKAR1A These observations expand our understanding of the pathogenesis of ADPKD and demonstrate the importance of PRKAR1A highlighting PKA as a therapeutic target in ADPKD.
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Affiliation(s)
- Hong Ye
- Mayo Clinic, Rochester Minnesota; and
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Schenk H, Müller-Deile J, Kinast M, Schiffer M. Disease modeling in genetic kidney diseases: zebrafish. Cell Tissue Res 2017; 369:127-141. [PMID: 28331970 DOI: 10.1007/s00441-017-2593-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 02/22/2017] [Indexed: 01/07/2023]
Abstract
Growing numbers of translational genomics studies are based on the highly efficient and versatile zebrafish (Danio rerio) vertebrate model. The increasing types of zebrafish models have improved our understanding of inherited kidney diseases, since they not only display pathophysiological changes but also give us the opportunity to develop and test novel treatment options in a high-throughput manner. New paradigms in inherited kidney diseases have been developed on the basis of the distinct genome conservation of approximately 70 % between zebrafish and humans in terms of existing gene orthologs. Several options are available to determine the functional role of a specific gene or gene sets. Permanent genome editing can be induced via complete gene knockout by using the CRISPR/Cas-system, among others, or via transient modification by using various morpholino techniques. Cross-species rescues succeeding knockdown techniques are employed to determine the functional significance of a target gene or a specific mutation. This article summarizes the current techniques and discusses their perspectives.
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Affiliation(s)
- Heiko Schenk
- Department of Medicine/Nephrology, Hannover Medical School, Hannover, Germany
- Mount Desert Island Biological Laboratory, Salisbury Cove, Bar Harbor, Me., USA
| | - Janina Müller-Deile
- Department of Medicine/Nephrology, Hannover Medical School, Hannover, Germany
- Mount Desert Island Biological Laboratory, Salisbury Cove, Bar Harbor, Me., USA
| | - Mark Kinast
- Department of Medicine/Nephrology, Hannover Medical School, Hannover, Germany
- Mount Desert Island Biological Laboratory, Salisbury Cove, Bar Harbor, Me., USA
| | - Mario Schiffer
- Department of Medicine/Nephrology, Hannover Medical School, Hannover, Germany.
- Mount Desert Island Biological Laboratory, Salisbury Cove, Bar Harbor, Me., USA.
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