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Nagpal S, Swaminathan K, Beaudet D, Verdier M, Wang S, Berger CL, Berger F, Hendricks AG. Optogenetic control of kinesin-1, -2, -3 and dynein reveals their specific roles in vesicular transport. Cell Rep 2024; 43:114649. [PMID: 39159044 DOI: 10.1016/j.celrep.2024.114649] [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: 06/30/2023] [Revised: 07/04/2024] [Accepted: 08/01/2024] [Indexed: 08/21/2024] Open
Abstract
Each cargo in a cell employs a unique set of motor proteins for its transport. To dissect the roles of each type of motor, we developed optogenetic inhibitors of endogenous kinesin-1, -2, -3 and dynein motors and examined their effect on the transport of early endosomes, late endosomes, and lysosomes. While kinesin-1, -3, and dynein transport vesicles at all stages of endocytosis, kinesin-2 primarily drives late endosomes and lysosomes. Transient optogenetic inhibition of kinesin-1 or dynein causes both early and late endosomes to move more processively by relieving competition with opposing motors. Kinesin-2 and -3 support long-range transport, and optogenetic inhibition reduces the distances that their cargoes move. These results suggest that the directionality of transport is controlled through regulating kinesin-1 and dynein activity. On vesicles transported by several kinesin and dynein motors, modulating the activity of a single type of motor on the cargo is sufficient to direct motility.
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Affiliation(s)
- Sahil Nagpal
- Department of Bioengineering, McGill University, Montreal, QC H3A 0E9, Canada
| | | | - Daniel Beaudet
- Department of Bioengineering, McGill University, Montreal, QC H3A 0E9, Canada
| | - Maud Verdier
- Department of Bioengineering, McGill University, Montreal, QC H3A 0E9, Canada; Department of Biomedical Engineering and Health, Episen, Université Paris-Est Créteil, 94010 Créteil Cedex, France
| | - Samuel Wang
- Department of Bioengineering, McGill University, Montreal, QC H3A 0E9, Canada
| | - Christopher L Berger
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, VT 05405-0075, USA
| | - Florian Berger
- Cell Biology, Neurobiology, and Biophysics, Department of Biology, Utrecht University, Utrecht, the Netherlands
| | - Adam G Hendricks
- Department of Bioengineering, McGill University, Montreal, QC H3A 0E9, Canada.
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2
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Walker MF, Zhang J, Steiner W, Ku PI, Zhu JF, Michaelson Z, Yen YC, Lee A, Long AB, Casey MJ, Poddar A, Nelson IB, Arveseth CD, Nagel F, Clough R, LaPotin S, Kwan KM, Schulz S, Stewart RA, Tesmer JJG, Caspary T, Subramanian R, Ge X, Myers BR. GRK2 kinases in the primary cilium initiate SMOOTHENED-PKA signaling in the Hedgehog cascade. PLoS Biol 2024; 22:e3002685. [PMID: 39138140 PMCID: PMC11322411 DOI: 10.1371/journal.pbio.3002685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 05/21/2024] [Indexed: 08/15/2024] Open
Abstract
During Hedgehog (Hh) signal transduction in development and disease, the atypical G protein-coupled receptor (GPCR) SMOOTHENED (SMO) communicates with GLI transcription factors by binding the protein kinase A catalytic subunit (PKA-C) and physically blocking its enzymatic activity. Here, we show that GPCR kinase 2 (GRK2) orchestrates this process during endogenous mouse and zebrafish Hh pathway activation in the primary cilium. Upon SMO activation, GRK2 rapidly relocalizes from the ciliary base to the shaft, triggering SMO phosphorylation and PKA-C interaction. Reconstitution studies reveal that GRK2 phosphorylation enables active SMO to bind PKA-C directly. Lastly, the SMO-GRK2-PKA pathway underlies Hh signal transduction in a range of cellular and in vivo models. Thus, GRK2 phosphorylation of ciliary SMO and the ensuing PKA-C binding and inactivation are critical initiating events for the intracellular steps in Hh signaling. More broadly, our study suggests an expanded role for GRKs in enabling direct GPCR interactions with diverse intracellular effectors.
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Affiliation(s)
- Madison F. Walker
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Jingyi Zhang
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, California, United States of America
| | - William Steiner
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Pei-I Ku
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, USA; Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Ju-Fen Zhu
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Zachary Michaelson
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Yu-Chen Yen
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
| | - Annabel Lee
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Alyssa B. Long
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Mattie J. Casey
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Abhishek Poddar
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, USA; Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Isaac B. Nelson
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Corvin D. Arveseth
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | | | - Ryan Clough
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Sarah LaPotin
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Kristen M. Kwan
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Stefan Schulz
- 7TM Antibodies GmbH, Jena, Germany
- Institute of Pharmacology and Toxicology, University Hospital Jena, Jena, Germany
| | - Rodney A. Stewart
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - John J. G. Tesmer
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana, United States of America
| | - Tamara Caspary
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Radhika Subramanian
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, USA; Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Xuecai Ge
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, California, United States of America
| | - Benjamin R. Myers
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
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3
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Hoard TM, Liu K, Cadigan KM, Giger RJ, Allen BL. Semaphorin Receptors Antagonize Wnt Signaling Through Beta-Catenin Degradation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.29.596372. [PMID: 38854152 PMCID: PMC11160715 DOI: 10.1101/2024.05.29.596372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Precise control of morphogen signaling levels is essential for proper development. An outstanding question is: what mechanisms ensure proper morphogen activity and correct cellular responses? Previous work has identified Semaphorin (SEMA) receptors, Neuropilins (NRPs) and Plexins (PLXNs), as positive regulators of the Hedgehog (HH) signaling pathway. Here, we provide evidence that NRPs and PLXNs antagonize Wnt signaling in both fibroblasts and epithelial cells. Further, Nrp1/2 deletion in fibroblasts results in elevated baseline Wnt pathway activity and increased maximal responses to Wnt stimulation. Notably, and in contrast to HH signaling, SEMA receptor-mediated Wnt antagonism is independent of primary cilia. Mechanistically, PLXNs and NRPs act downstream of Dishevelled (DVL) to destabilize β-catenin (CTNNB1) in a proteosome-dependent manner. Further, NRPs, but not PLXNs, act in a GSK3β/CK1-dependent fashion to antagonize Wnt signaling, suggesting distinct repressive mechanisms for these SEMA receptors. Overall, this study identifies SEMA receptors as novel Wnt pathway antagonists that may also play larger roles integrating signals from multiple inputs.
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Affiliation(s)
- Tyler M Hoard
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Katie Liu
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Kenneth M Cadigan
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Roman J Giger
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Benjamin L Allen
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
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4
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Tingey M, Ruba A, Jiang Z, Yang W. Deciphering vesicle-assisted transport mechanisms in cytoplasm to cilium trafficking. Front Cell Neurosci 2024; 18:1379976. [PMID: 38860265 PMCID: PMC11163138 DOI: 10.3389/fncel.2024.1379976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 05/13/2024] [Indexed: 06/12/2024] Open
Abstract
The cilium, a pivotal organelle crucial for cell signaling and proper cell function, relies on meticulous macromolecular transport from the cytoplasm for its formation and maintenance. While the intraflagellar transport (IFT) pathway has traditionally been the focus of extensive study concerning ciliogenesis and ciliary maintenance, recent research highlights a complementary and alternative mechanism-vesicle-assisted transport (VAT) in cytoplasm to cilium trafficking. Despite its potential significance, the VAT pathway remains largely uncharacterized. This review explores recent studies providing evidence for the dynamics of vesicle-related diffusion and transport within the live primary cilium, employing high-speed super-resolution light microscopy. Additionally, we analyze the spatial distribution of vesicles in the cilium, mainly relying on electron microscopy data. By scrutinizing the VAT pathways that facilitate cargo transport into the cilium, with a specific emphasis on recent advancements and imaging data, our objective is to synthesize a comprehensive model of ciliary transport through the integration of IFT-VAT mechanisms.
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Affiliation(s)
| | | | | | - Weidong Yang
- Department of Biology, Temple University, Philadelphia, PA, United States
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5
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Waas B, Carpenter BS, Franks NE, Merchant OQ, Verhey KJ, Allen BL. Dual and opposing roles for the kinesin-2 motor, KIF17, in Hedgehog-dependent cerebellar development. SCIENCE ADVANCES 2024; 10:eade1650. [PMID: 38669326 PMCID: PMC11051677 DOI: 10.1126/sciadv.ade1650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 03/26/2024] [Indexed: 04/28/2024]
Abstract
While the kinesin-2 motors KIF3A and KIF3B have essential roles in ciliogenesis and Hedgehog (HH) signal transduction, potential role(s) for another kinesin-2 motor, KIF17, in HH signaling have yet to be explored. Here, we investigated the contribution of KIF17 to HH-dependent cerebellar development, where Kif17 is expressed in both HH-producing Purkinje cells and HH-responding cerebellar granule neuron progenitors (CGNPs). Germline Kif17 deletion in mice results in cerebellar hypoplasia due to reduced CGNP proliferation, a consequence of decreased HH pathway activity mediated through decreased Sonic HH (SHH) protein. Notably, Purkinje cell-specific Kif17 deletion partially phenocopies Kif17 germline mutants. Unexpectedly, CGNP-specific Kif17 deletion results in the opposite phenotype-increased CGNP proliferation and HH target gene expression due to altered GLI transcription factor processing. Together, these data identify KIF17 as a key regulator of HH-dependent cerebellar development, with dual and opposing roles in HH-producing Purkinje cells and HH-responding CGNPs.
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Affiliation(s)
- Bridget Waas
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Brandon S. Carpenter
- Department of Molecular and Cellular Biology, College of Science and Mathematics, Kennesaw State University, Kennesaw, GA, 30061, USA
| | - Nicole E. Franks
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Olivia Q. Merchant
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Kristen J. Verhey
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Benjamin L. Allen
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
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6
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Adams JM, Sawe C, Rogers S, Reid J, Dasari R, Engelke MF. Characterization of the disease-causing mechanism of KIF3B mutations from ciliopathy patients. Front Mol Biosci 2024; 11:1327963. [PMID: 38665936 PMCID: PMC11043552 DOI: 10.3389/fmolb.2024.1327963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 03/04/2024] [Indexed: 04/28/2024] Open
Abstract
The heterodimeric kinesin-2 motor (KIF3A/KIF3B with accessory protein KAP3) drives intraflagellar transport, essential for ciliogenesis and ciliary function. Three point mutations in the KIF3B subunit have recently been linked to disease in humans (E250Q and L523P) and Bengal cats (A334T) (Cogné et al., Am. J. Hum. Genet., 2020, 106, 893-904). Patients display retinal atrophy and, in some cases, other ciliopathy phenotypes. However, the molecular mechanism leading to disease is currently unknown. Here, we used Kif3a -/- ;Kif3b -/- (knockout) 3T3 cells, which cannot make cilia, to characterize these mutations. While reexpression of KIF3B(E250Q) and KIF3B(L523P) did not rescue ciliogenesis, reexpression of wildtype or KIF3B(A334T) restored ciliogenesis to wildtype levels. Fluorescent tagging revealed that the E250Q mutant decorated microtubules and thus is a rigor mutation. The L523P mutation, in the alpha-helical stalk domain, surprisingly did not affect formation of the KIF3A/KIF3B/KAP3 complex but instead impaired motility along microtubules. Lastly, expression of the A334T motor was reduced in comparison to all other motors, and this motor displayed an impaired ability to disperse the Golgi complex when artificially linked to this high-load cargo. In summary, this work uses cell-based assays to elucidate the molecular effects of disease-causing mutations in the KIF3B subunit on the kinesin-2 holoenzyme.
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Affiliation(s)
| | | | | | | | | | - Martin F. Engelke
- School of Biological Sciences, Cell Physiology, Illinois State University, Normal, IL, United States
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7
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Fasawe AS, Adams JM, Engelke MF. KIF3A tail domain phosphorylation is not required for ciliogenesis in mouse embryonic fibroblasts. iScience 2024; 27:109149. [PMID: 38405607 PMCID: PMC10884758 DOI: 10.1016/j.isci.2024.109149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 11/21/2023] [Accepted: 02/01/2024] [Indexed: 02/27/2024] Open
Abstract
Primary cilia are essential signaling organelles that protrude from most cells in the body. Heterodimeric kinesin-2 (KIF3A/KIF3B/KAP3) powers several intracellular transport processes, including intraflagellar transport (IFT), essential for ciliogenesis. A long-standing question is how a motor protein is differentially regulated for specific cargos. Since phosphorylation of the KIF3A tail domain was suggested to regulate the activity of kinesin-2 for ciliogenesis, similarly as for the cytosolic cargo N-Cadherin, we set out to map the phosphosites involved in this regulation. Using well-characterized Kif3a-/-; Kif3b-/- mouse embryonic fibroblasts, we performed ciliogenesis rescue assays with a library of phosphomimetic mutants comprising all predicted phosphosites in the KIF3A tail domain. In contrast to previous reports, we found that KIF3A tail domain phosphorylation is dispensable for ciliogenesis in mammals. Thus, mammalian kinesin-2 is differently regulated for IFT than currently thought, consistent with the idea of differential regulation for ciliary and cytosolic cargo.
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Affiliation(s)
- Ayoola S. Fasawe
- School of Biological Sciences, Cell Physiology, Illinois State University, Normal, IL 61790, USA
| | - Jessica M. Adams
- School of Biological Sciences, Cell Physiology, Illinois State University, Normal, IL 61790, USA
| | - Martin F. Engelke
- School of Biological Sciences, Cell Physiology, Illinois State University, Normal, IL 61790, USA
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8
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Jung HJ, Dixon EE, Coleman R, Watnick T, Reiter JF, Outeda P, Cebotaru V, Woodward OM, Welling PA. Polycystin-2-dependent transcriptome reveals early response of autosomal dominant polycystic kidney disease. Physiol Genomics 2023; 55:565-577. [PMID: 37720991 PMCID: PMC11178268 DOI: 10.1152/physiolgenomics.00040.2023] [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: 05/15/2023] [Revised: 09/12/2023] [Accepted: 09/13/2023] [Indexed: 09/19/2023] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutations in polycystin genes, Pkd1 and Pkd2, but the underlying pathogenic mechanisms are poorly understood. To identify genes and pathways that operate downstream of polycystin-2 (PC2), a comprehensive gene expression database was created, cataloging changes in the transcriptome immediately following PC2 protein depletion. To explore cyst initiation processes, an immortalized mouse inner medullary collecting duct line was developed with the ability to knock out the Pkd2 gene conditionally. Genome-wide transcriptome profiling was performed using RNA sequencing in the cells immediately after PC2 was depleted and compared with isogenic control cells. Differentially expressed genes were identified, and a bioinformatic analysis pipeline was implemented. Altered expression of candidate cystogenic genes was validated in Pkd2 knockout mice. The expression of nearly 900 genes changed upon PC2 depletion. Differentially expressed genes were enriched for genes encoding components of the primary cilia, the canonical Wnt pathway, and MAPK signaling. Among the PC2-dependent ciliary genes, the transcription factor Glis3 was significantly downregulated. MAPK signaling formed a key node at the epicenter of PC2-dependent signaling networks. Activation of Wnt and MAPK signaling, concomitant with the downregulation of Glis3, was corroborated in Pkd2 knockout mice. The data identify a PC2 cilia-to-nucleus signaling axis and dysregulation of the Gli-similar subfamily of transcription factors as a potential initiator of cyst formation in ADPKD. The catalog of PC2-regulated genes should provide a valuable resource for future ADPKD research and new opportunities for drug development.NEW & NOTEWORTHY Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease. Mutations in polycystin genes cause the disease, but the underlying mechanisms of cystogenesis are unknown. To help fill this knowledge gap, we created an inducible cell model of ADPKD and assembled a catalog of genes that respond in immediate proximity to polycystin-2 depletion using transcriptomic profiling. The catalog unveils a ciliary signaling-to-nucleus axis proximal to polycystin-2 dysfunction, highlighting Glis, Wnt, and MAPK signaling.
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Affiliation(s)
- Hyun Jun Jung
- Division of Nephrology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Eryn E Dixon
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States
| | - Richard Coleman
- Division of Nephrology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Terry Watnick
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, United States
| | - Jeremy F Reiter
- Department of Biochemistry and Biophysics, University of California, San Francisco, California, United States
- Chan Zuckerberg Biohub, San Francisco, California, United States
| | - Patricia Outeda
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, United States
| | - Valeriu Cebotaru
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, United States
| | - Owen M Woodward
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States
| | - Paul A Welling
- Division of Nephrology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
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9
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Arora S, Rana M, Sachdev A, D’Souza JS. Appearing and disappearing acts of cilia. J Biosci 2023. [DOI: 10.1007/s12038-023-00326-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
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10
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Ishikawa H, Moore J, Diener DR, Delling M, Marshall WF. Testing the ion-current model for flagellar length sensing and IFT regulation. eLife 2023; 12:82901. [PMID: 36637158 PMCID: PMC9891718 DOI: 10.7554/elife.82901] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 01/12/2023] [Indexed: 01/14/2023] Open
Abstract
Eukaryotic cilia and flagella are microtubule-based organelles whose relatively simple shape makes them ideal for investigating the fundamental question of organelle size regulation. Most of the flagellar materials are transported from the cell body via an active transport process called intraflagellar transport (IFT). The rate of IFT entry into flagella, known as IFT injection, has been shown to negatively correlate with flagellar length. However, it remains unknown how the cell measures the length of its flagella and controls IFT injection. One of the most-discussed theoretical models for length sensing to control IFT is the ion-current model, which posits that there is a uniform distribution of Ca2+ channels along the flagellum and that the Ca2+ current from the flagellum into the cell body increases linearly with flagellar length. In this model, the cell uses the Ca2+ current to negatively regulate IFT injection. The recent discovery that IFT entry into flagella is regulated by the phosphorylation of kinesin through a calcium-dependent protein kinase has provided further impetus for the ion-current model. To test this model, we measured and manipulated the levels of Ca2+ inside of Chlamydomonas flagella and quantified IFT injection. Although the concentration of Ca2+ inside of flagella was weakly correlated with the length of flagella, we found that IFT injection was reduced in calcium-deficient flagella, rather than increased as the model predicted, and that variation in IFT injection was uncorrelated with the occurrence of flagellar Ca2+ spikes. Thus, Ca2+ does not appear to function as a negative regulator of IFT injection, hence it cannot form the basis of a stable length control system.
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Affiliation(s)
- Hiroaki Ishikawa
- Department of Biochemistry and Biophysics, University of California, San FranciscoSan FranciscoUnited States
| | - Jeremy Moore
- Kenyon College, Gambier, and Summer Research Training Program at University of California San FranciscoSan FranciscoUnited States
| | - Dennis R Diener
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
| | - Markus Delling
- Department of Physiology, University of California, San FranciscoSan FranciscoUnited States
| | - Wallace F Marshall
- Department of Biochemistry and Biophysics, University of California, San FranciscoSan FranciscoUnited States
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11
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Liu S, He Y, Li S, Gao X, Yang F. Kinesin family member 3A induces related diseases via wingless-related integration site/β-catenin signaling pathway. Sci Prog 2023; 106:368504221148340. [PMID: 36594221 PMCID: PMC10358705 DOI: 10.1177/00368504221148340] [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] [Indexed: 01/04/2023]
Abstract
Kinesin family member 3A is an important motor protein that participates in various physiological and pathological processes, including normal tissue development, homeostasis maintenance, tumor infiltration, and migration. The wingless-related integration site/β-catenin signaling pathway is essential for critical molecular mechanisms such as embryonic development, organogenesis, tissue regeneration, and carcinogenesis. Recent studies have examined the molecular mechanisms of kinesin family member 3A, among which the wingless-related integration site/β-catenin signaling pathway has gained attention. The interaction between kinesin family member 3A and the wingless-related integration site/β-catenin signaling pathway is compact and complex but is fascinating and worthy of further study. The upregulation and downregulation of kinesin family member 3A influence many diseases and patient survival through the wingless-related integration site/β-catenin signaling pathway. Therefore, this review mainly focuses on describing the kinesin family member 3A and wingless-related integration site/β-catenin signaling pathways and their associated diseases.
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Affiliation(s)
- Shupeng Liu
- Hebei Key Laboratory for Organ Fibrosis Research, School of Public Health, North China University of Science and Technology, Tangshan, Hebei Province, China
| | - Yang He
- Clinical Medicine College, North China University of Science and Technology, Tangshan, Hebei province, China
| | - Shifeng Li
- Hebei Key Laboratory for Organ Fibrosis Research, School of Public Health, North China University of Science and Technology, Tangshan, Hebei Province, China
| | - Xuemin Gao
- NHC Key Laboratory of Pneumoconiosis, Taiyuan, Shanxi Province, China
| | - Fang Yang
- Hebei Key Laboratory for Organ Fibrosis Research, School of Public Health, North China University of Science and Technology, Tangshan, Hebei Province, China
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12
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Arora S, Rana M, Sachdev A, D'Souza JS. Appearing and disappearing acts of cilia. J Biosci 2023; 48:8. [PMID: 36924208 PMCID: PMC10005925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
The past few decades have seen a rise in research on vertebrate cilia and ciliopathy, with interesting collaborations between basic and clinical scientists. This work includes studies on ciliary architecture, composition, evolution, and organelle generation and its biological role. The human body has cells that harbour any of the following four types of cilia: 9+0 motile, 9+0 immotile, 9+2 motile, and 9+2 immotile. Depending on the type, cilia play an important role in cell/fluid movement, mating, sensory perception, and development. Defects in cilia are associated with a wide range of human diseases afflicting the brain, heart, kidneys, respiratory tract, and reproductive system. These are commonly known as ciliopathies and affect millions of people worldwide. Due to their complex genetic etiology, diagnosis and therapy have remained elusive. Although model organisms like Chlamydomonas reinhardtii have been a useful source for ciliary research, reports of a fascinating and rewarding translation of this research into mammalian systems, especially humans, are seen. The current review peeks into one of the complex features of this organelle, namely its birth, the common denominators across the formation of both 9+0 and 9+2 ciliary types, the molecules involved in ciliogenesis, and the steps that go towards regulating their assembly and disassembly.
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Affiliation(s)
- Shashank Arora
- School of Biological Sciences, UM-DAE Centre for Excellence in Basic Sciences, Kalina Campus, Santacruz (E), Mumbai 400098, India
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13
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Garbouchian A, Montgomery AC, Gilbert SP, Bentley M. KAP is the neuronal organelle adaptor for Kinesin-2 KIF3AB and KIF3AC. Mol Biol Cell 2022; 33:ar133. [PMID: 36200888 PMCID: PMC9727798 DOI: 10.1091/mbc.e22-08-0336] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Kinesin-driven organelle transport is crucial for neuron development and maintenance, yet the mechanisms by which kinesins specifically bind their organelle cargoes remain undefined. In contrast to other transport kinesins, the neuronal function and specific organelle adaptors of heterodimeric Kinesin-2 family members KIF3AB and KIF3AC remain unknown. We developed a novel microscopy-based assay to define protein-protein interactions in intact neurons. The experiments found that both KIF3AB and KIF3AC bind kinesin-associated protein (KAP). These interactions are mediated by the distal C-terminal tail regions and not the coiled-coil domain. We used live-cell imaging in cultured hippocampal neurons to define the localization and trafficking parameters of KIF3AB and KIF3AC organelle populations. We discovered that KIF3AB/KAP and KIF3AC/KAP bind the same organelle populations and defined their transport parameters in axons and dendrites. The results also show that ∼12% of KIF3 organelles contain the RNA-binding protein adenomatous polyposis coli. These data point toward a model in which KIF3AB and KIF3AC use KAP as their neuronal organelle adaptor and that these kinesins mediate transport of a range of organelles.
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Affiliation(s)
- Alex Garbouchian
- Department of Biological Sciences and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Andrew C. Montgomery
- Department of Biological Sciences and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Susan P. Gilbert
- Department of Biological Sciences and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Marvin Bentley
- Department of Biological Sciences and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180,*Address correspondence to: Marvin Bentley ()
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14
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Hu Z, Meng J, Cai H, Ma N, Gao X, Li X, Xu Y. KIF3A inhibits nasopharyngeal carcinoma proliferation, migration and invasion by interacting with β-catenin to suppress its nuclear accumulation. Am J Cancer Res 2022; 12:5226-5240. [PMID: 36504907 PMCID: PMC9729906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 11/12/2022] [Indexed: 12/15/2022] Open
Abstract
Nasopharyngeal carcinoma (NPC) is a malignant epithelial tumor prevalent in southern China and Southeast Asia. Previous studies have shown that Kinesin Family Member 3A (KIF3A) plays a critical role in the oncogenesis of various cancer types. However, the role of KIF3A in NPC tumorigenesis and the mechanism underlying its function have not been reported. In this study, we found that KIF3A was significantly downregulated in NPC cells and tissues, and KIF3A expression in NPC patients was associated with tumor stage and was positively corrected with overall survival. In vitro and in vivo experiments indicated that overexpression of KIF3A inhibited NPC cell proliferation, migration, and invasion. Mechanistic studies found that KIF3A bound β-catenin and attenuated β-catenin aggregation in the nucleus. Moreover, rescue experiments demonstrated that the inhibitory effect of KIF3A on NPC proliferation, migration and invasion was partially dependent on β-catenin. Taken together, our data suggest that KIF3A interacts with β-catenin and attenuates NPC proliferation, migration, and invasion by suppressing the intranuclear aggregation of β-catenin. KIF3A may be a promising therapeutic target of patients with NPC.
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Affiliation(s)
- Zhe Hu
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical UniversityGuangzhou 510315, Guangdong, China
| | - Jinlan Meng
- Department of Physiology, School of Life Sciences and Biopharmaceutics, Guangdong Pharmaceutical UniversityGuangzhou 510006, Guangdong, China
| | - Hongbing Cai
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical UniversityGuangzhou 510315, Guangdong, China
| | - Na Ma
- Department of Physiology, School of Life Sciences and Biopharmaceutics, Guangdong Pharmaceutical UniversityGuangzhou 510006, Guangdong, China
| | - Xiujie Gao
- Department of Physiology, School of Life Sciences and Biopharmaceutics, Guangdong Pharmaceutical UniversityGuangzhou 510006, Guangdong, China
| | - Xiaojuan Li
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical UniversityGuangzhou 510315, Guangdong, China
| | - Yan Xu
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical UniversityGuangzhou 510315, Guangdong, China
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15
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Mechanisms of Regulation in Intraflagellar Transport. Cells 2022; 11:cells11172737. [PMID: 36078145 PMCID: PMC9454703 DOI: 10.3390/cells11172737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 08/30/2022] [Accepted: 08/31/2022] [Indexed: 11/30/2022] Open
Abstract
Cilia are eukaryotic organelles essential for movement, signaling or sensing. Primary cilia act as antennae to sense a cell’s environment and are involved in a wide range of signaling pathways essential for development. Motile cilia drive cell locomotion or liquid flow around the cell. Proper functioning of both types of cilia requires a highly orchestrated bi-directional transport system, intraflagellar transport (IFT), which is driven by motor proteins, kinesin-2 and IFT dynein. In this review, we explore how IFT is regulated in cilia, focusing from three different perspectives on the issue. First, we reflect on how the motor track, the microtubule-based axoneme, affects IFT. Second, we focus on the motor proteins, considering the role motor action, cooperation and motor-train interaction plays in the regulation of IFT. Third, we discuss the role of kinases in the regulation of the motor proteins. Our goal is to provide mechanistic insights in IFT regulation in cilia and to suggest directions of future research.
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16
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The physiological cargo adaptor of kinesin-2 functions as an evolutionary conserved lockpick. Proc Natl Acad Sci U S A 2022; 119:e2109378119. [PMID: 35947619 PMCID: PMC9388150 DOI: 10.1073/pnas.2109378119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Specific recognition of cellular cargo and efficient transport to its correct intracellular destination is an infrastructural challenge faced by most eukaryotic cells. This remarkable deed is accomplished by processive motor proteins that are subject to robust regulatory mechanisms. The first level of regulation entails the ability of the motor to suppress its own activity. This autoinhibition is eventually relieved by specific cargo binding. To better understand the role of the cargo during motor activation, we dissected the activation mechanism of the ciliary homodimeric kinesin-2 from Caenorhabditis elegans by its physiological cargo. In functional reconstitution assays, we identified two cargo adaptor proteins that together are necessary and sufficient to allosterically activate the autoinhibited motor. Surprisingly, the orthologous adaptor proteins from the unicellular green algae Chlamydomonas reinhardtii also fully activated the kinesin-2 from worm, even though C. reinhardtii itself lacks a homodimeric kinesin-2 motor. The latter suggested that a motor activation mechanism similar to the C. elegans model existed already well before metazoans evolved, and prompted us to scrutinize predicted homodimeric kinesin-2 orthologs in other evolutionarily distant eukaryotes. We show that the ciliate Tetrahymena thermophila not only possesses a homodimeric kinesin-2 but that it also shares the same allosteric activation mechanism that we delineated in the C. elegans model. Our results point to a much more fundamental role of homodimeric kinesin-2 in intraflagellar transport (IFT) than previously thought and warrant further scrutiny of distantly related organisms toward a comprehensive picture of the IFT process and its evolution.
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Loss of KAP3 decreases intercellular adhesion and impairs intracellular transport of laminin in signet ring cell carcinoma of the stomach. Sci Rep 2022; 12:5050. [PMID: 35322078 PMCID: PMC8943207 DOI: 10.1038/s41598-022-08904-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 03/14/2022] [Indexed: 12/14/2022] Open
Abstract
Signet-ring cell carcinoma (SRCC) is a unique subtype of gastric cancer that is impaired for cell-cell adhesion. The pathogenesis of SRCC remains unclear. Here, we show that expression of kinesin-associated protein 3 (KAP3), a cargo adaptor subunit of the kinesin superfamily protein 3 (KIF3), a motor protein, is specifically decreased in SRCC of the stomach. CRISPR/Cas9-mediated gene knockout experiments indicated that loss of KAP3 impairs the formation of circumferential actomyosin cables by inactivating RhoA, leading to the weakening of cell-cell adhesion. Furthermore, in KAP3 knockout cells, post-Golgi transport of laminin, a key component of the basement membrane, was inhibited, resulting in impaired basement membrane formation. Together, these findings uncover a potential role for KAP3 in the pathogenesis of SRCC of the stomach.
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Ift88, but not Kif3a, is required for establishment of the periciliary membrane compartment. Biochem Biophys Res Commun 2021; 584:19-25. [PMID: 34753064 DOI: 10.1016/j.bbrc.2021.10.075] [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: 09/17/2021] [Accepted: 10/29/2021] [Indexed: 11/22/2022]
Abstract
The primary cilium is a sensory organelle at the cell surface with integral functions in cell signaling. It contains a microtubular axoneme that is rooted in the basal body (BB) and serves as a scaffold for the movement of intraflagellar transport (IFT) particles by Kinesin-2 along the cilium. Ift88, a member of the anterograde moving IFT-B1 complex, as well as the Kinesin-2 subunit Kif3a are required for cilia formation. To facilitate signaling, the cilium restricts the access of molecules to its membrane ("ciliary gate"). This is thought to be mediated by cytoskeletal barriers ("subciliary domains") originating from the BB subdistal/distal appendages, the periciliary membrane compartment (PCMC) as well as the transition fibers and zone (TF/TZ). The PCMC is a poorly characterized membrane domain surrounding the ciliary base with exclusion of certain apical membrane proteins. Here we describe that Ift88, but not Kinesin-2, is required for the establishment of the PCMC in MDCK cells. Likewise, in C. elegans mutants of the Ift88 ortholog osm-5 fail to establish the PCMC, while Kinesin-2 deficient osm-3 mutants form PCMCs normally. Furthermore, disruption of IFT-B1 into two subcomplexes, while disrupting ciliogenesis, does not interfere with PCMC formation. Our findings suggest that cilia are not a prerequisite for the formation of the PCMC, and that separate machineries with partially overlapping functions are required for the establishment of each.
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Yue Y, Engelke MF, Blasius TL, Verhey KJ. Hedgehog-induced ciliary trafficking of kinesin-4 motor KIF7 requires intraflagellar transport but not KIF7's microtubule binding. Mol Biol Cell 2021; 33:br1. [PMID: 34705483 PMCID: PMC8886809 DOI: 10.1091/mbc.e21-04-0215] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The kinesin-4 motor KIF7 is a conserved regulator of the Hedgehog signaling pathway. In vertebrates, Hedgehog signaling requires the primary cilium, and KIF7 and Gli transcription factors accumulate at the cilium tip in response to Hedgehog activation. Unlike conventional kinesins, KIF7 is an immotile kinesin and its mechanism of ciliary accumulation is unknown. We generated KIF7 variants with altered microtubule binding or motility. We demonstrate that microtubule binding of KIF7 is not required for the increase in KIF7 or Gli localization at the cilium tip in response to Hedgehog signaling. In addition, we show that the immotile behavior of KIF7 is required to prevent ciliary localization of Gli transcription factors in the absence of Hedgehog signaling. Using an engineered kinesin-2 motor that enables acute inhibition of intraflagellar transport, we demonstrate that kinesin-2 KIF3A/KIF3B/KAP mediates the translocation of KIF7 to the cilium tip in response to Hedgehog pathway activation. Together, these results suggest that KIF7’s role at the tip of the cilium is unrelated to its ability to bind to microtubules.
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Affiliation(s)
- Yang Yue
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Martin F Engelke
- School of Biological Sciences, Illinois State University, Normal, IL 61790, USA
| | - T Lynne Blasius
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Kristen J Verhey
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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20
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Loo CKC, Pearen MA, Ramm GA. The Role of Sonic Hedgehog in Human Holoprosencephaly and Short-Rib Polydactyly Syndromes. Int J Mol Sci 2021; 22:ijms22189854. [PMID: 34576017 PMCID: PMC8468456 DOI: 10.3390/ijms22189854] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/03/2021] [Accepted: 09/09/2021] [Indexed: 12/18/2022] Open
Abstract
The Hedgehog (HH) signalling pathway is one of the major pathways controlling cell differentiation and proliferation during human development. This pathway is complex, with HH function influenced by inhibitors, promotors, interactions with other signalling pathways, and non-genetic and cellular factors. Many aspects of this pathway are not yet clarified. The main features of Sonic Hedgehog (SHH) signalling are discussed in relation to its function in human development. The possible role of SHH will be considered using examples of holoprosencephaly and short-rib polydactyly (SRP) syndromes. In these syndromes, there is wide variability in phenotype even with the same genetic mutation, so that other factors must influence the outcome. SHH mutations were the first identified genetic causes of holoprosencephaly, but many other genes and environmental factors can cause malformations in the holoprosencephaly spectrum. Many patients with SRP have genetic defects affecting primary cilia, structures found on most mammalian cells which are thought to be necessary for canonical HH signal transduction. Although SHH signalling is affected in both these genetic conditions, there is little overlap in phenotype. Possible explanations will be canvassed, using data from published human and animal studies. Implications for the understanding of SHH signalling in humans will be discussed.
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Affiliation(s)
- Christine K. C. Loo
- South Eastern Area Laboratory Services, Department of Anatomical Pathology, NSW Health Pathology, Prince of Wales Hospital, Sydney, NSW 2031, Australia
- Correspondence: ; Tel.: +61-2-93829015
| | - Michael A. Pearen
- Hepatic Fibrosis Group, Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Brisbane, QLD 4006, Australia; (M.A.P.); (G.A.R.)
| | - Grant A. Ramm
- Hepatic Fibrosis Group, Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Brisbane, QLD 4006, Australia; (M.A.P.); (G.A.R.)
- Faculty of Medicine, The University of Queensland, Brisbane, QLD 4006, Australia
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21
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Lam WY, Tang CSM, So MT, Yue H, Hsu JS, Chung PHY, Nicholls JM, Yeung F, Lee CWD, Ngo DN, Nguyen PAH, Mitchison HM, Jenkins D, O'Callaghan C, Garcia-Barceló MM, Lee SL, Sham PC, Lui VCH, Tam PKH. Identification of a wide spectrum of ciliary gene mutations in nonsyndromic biliary atresia patients implicates ciliary dysfunction as a novel disease mechanism. EBioMedicine 2021; 71:103530. [PMID: 34455394 PMCID: PMC8403738 DOI: 10.1016/j.ebiom.2021.103530] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 07/09/2021] [Accepted: 07/27/2021] [Indexed: 12/12/2022] Open
Abstract
Background Biliary atresia (BA) is the most common obstructive cholangiopathy in neonates, often progressing to end-stage cirrhosis. BA pathogenesis is believed to be multifactorial, but the genetic contribution, especially for nonsyndromic BA (common form: > 85%) remains poorly defined. Methods We conducted whole exome sequencing on 89 nonsyndromic BA trios to identify rare variants contributing to BA etiology. Functional evaluation using patients’ liver biopsies, human cell and zebrafish models were performed. Clinical impact on respiratory system was assessed with clinical evaluation, nasal nitric oxide (nNO), high speed video analysis and transmission electron microscopy. Findings We detected rare, deleterious de novo or biallelic variants in liver-expressed ciliary genes in 31.5% (28/89) of the BA patients. Burden test revealed 2.6-fold (odds ratio (OR) [95% confidence intervals (CI)]= 2.58 [1.15–6.07], adjusted p = 0.034) over-representation of rare, deleterious mutations in liver-expressed ciliary gene set in patients compared to controls. Functional analyses further demonstrated absence of cilia in the BA livers with KIF3B and TTC17 mutations, and knockdown of PCNT, KIF3B and TTC17 in human control fibroblasts and cholangiocytes resulted in reduced number of cilia. Additionally, CRISPR/Cas9-engineered zebrafish knockouts of KIF3B, PCNT and TTC17 displayed reduced biliary flow. Abnormally low level of nNO was detected in 80% (8/10) of BA patients carrying deleterious ciliary mutations, implicating the intrinsic ciliary defects. Interpretation Our findings support strong genetic susceptibility for nonsyndromic BA. Ciliary gene mutations leading to cholangiocyte cilia malformation and dysfunction could be a key biological mechanism in BA pathogenesis. Funding The study is supported by General Research Fund, HMRF Commissioned Paediatric Research at HKCH and Li Ka Shing Faculty of Medicine Enhanced New Staff Start-up Fund.
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Affiliation(s)
- Wai-Yee Lam
- Division of Paediatric Surgery, Department of Surgery, Li Ka Shing Faculty of Medicine, The University of Hong Kong, LKS Faculty of Medicine Building, 21 Sassoon Road, Hong Kong SAR, China; Dr Li Dak-Sum Research Centre, The University of Hong Kong, Hong Kong SAR, China
| | - Clara Sze-Man Tang
- Division of Paediatric Surgery, Department of Surgery, Li Ka Shing Faculty of Medicine, The University of Hong Kong, LKS Faculty of Medicine Building, 21 Sassoon Road, Hong Kong SAR, China; Dr Li Dak-Sum Research Centre, The University of Hong Kong, Hong Kong SAR, China
| | - Man-Ting So
- Division of Paediatric Surgery, Department of Surgery, Li Ka Shing Faculty of Medicine, The University of Hong Kong, LKS Faculty of Medicine Building, 21 Sassoon Road, Hong Kong SAR, China
| | - Haibing Yue
- Division of Paediatric Surgery, Department of Surgery, Li Ka Shing Faculty of Medicine, The University of Hong Kong, LKS Faculty of Medicine Building, 21 Sassoon Road, Hong Kong SAR, China
| | - Jacob Shujui Hsu
- Department of Psychiatry, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Patrick Ho-Yu Chung
- Division of Paediatric Surgery, Department of Surgery, Li Ka Shing Faculty of Medicine, The University of Hong Kong, LKS Faculty of Medicine Building, 21 Sassoon Road, Hong Kong SAR, China
| | - John M Nicholls
- Department of Pathology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Fanny Yeung
- Division of Paediatric Surgery, Department of Surgery, Li Ka Shing Faculty of Medicine, The University of Hong Kong, LKS Faculty of Medicine Building, 21 Sassoon Road, Hong Kong SAR, China
| | - Chun-Wai Davy Lee
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | | | | | - Hannah M Mitchison
- Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Dagan Jenkins
- Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Christopher O'Callaghan
- Respiratory, Critical Care & Anaesthesia Section, UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Maria-Mercè Garcia-Barceló
- Division of Paediatric Surgery, Department of Surgery, Li Ka Shing Faculty of Medicine, The University of Hong Kong, LKS Faculty of Medicine Building, 21 Sassoon Road, Hong Kong SAR, China
| | - So-Lun Lee
- Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, Hong Kong SAR, China
| | - Pak-Chung Sham
- Department of Psychiatry, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Vincent Chi-Hang Lui
- Division of Paediatric Surgery, Department of Surgery, Li Ka Shing Faculty of Medicine, The University of Hong Kong, LKS Faculty of Medicine Building, 21 Sassoon Road, Hong Kong SAR, China; Dr Li Dak-Sum Research Centre, The University of Hong Kong, Hong Kong SAR, China.
| | - Paul Kwong-Hang Tam
- Division of Paediatric Surgery, Department of Surgery, Li Ka Shing Faculty of Medicine, The University of Hong Kong, LKS Faculty of Medicine Building, 21 Sassoon Road, Hong Kong SAR, China; Dr Li Dak-Sum Research Centre, The University of Hong Kong, Hong Kong SAR, China.
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22
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Ho EK, Stearns T. Hedgehog signaling and the primary cilium: implications for spatial and temporal constraints on signaling. Development 2021; 148:dev195552. [PMID: 33914866 PMCID: PMC8126410 DOI: 10.1242/dev.195552] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The mechanisms of vertebrate Hedgehog signaling are linked to the biology of the primary cilium, an antenna-like organelle that projects from the surface of most vertebrate cell types. Although the advantages of restricting signal transduction to cilia are often noted, the constraints imposed are less frequently considered, and yet they are central to how Hedgehog signaling operates in developing tissues. In this Review, we synthesize current understanding of Hedgehog signal transduction, ligand secretion and transport, and cilia dynamics to explore the temporal and spatial constraints imposed by the primary cilium on Hedgehog signaling in vivo.
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Affiliation(s)
- Emily K. Ho
- Department of Developmental Biology, Stanford School of Medicine, Stanford, CA 94305, USA
| | - Tim Stearns
- Department of Biology, Stanford University, Stanford, CA 94305, USA
- Department of Genetics, Stanford School of Medicine, Stanford, CA 94305, USA
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23
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Yang Y, Chen M, Li J, Hong R, Yang J, Yu F, Li T, Yang S, Ran J, Guo C, Zhao Y, Luan Y, Liu M, Li D, Xie S, Zhou J. A cilium-independent role for intraflagellar transport 88 in regulating angiogenesis. Sci Bull (Beijing) 2021; 66:727-739. [PMID: 36654447 DOI: 10.1016/j.scib.2020.10.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 09/01/2020] [Accepted: 09/22/2020] [Indexed: 01/20/2023]
Abstract
Endothelial cilia are microtubule-based hair-like protrusions in the lumen ofblood vessels that function as fluid mechanosensors to regulate vascular hemodynamics.However, the functions of endothelial cilia in vascular development remain controversial. In this study, depletion of several key proteins responsible for ciliogenesis allows us to identify a cilium-independent role for intraflagellartransport88 (IFT88) in mammalian angiogenesis. Disruption of primary cilia by heat shock does not affect the angiogenic process. However, depletion of IFT88 significantly inhibits angiogenesis both in vitro and in vivo. IFT88 mediates angiogenesis by regulating the migration, polarization, proliferation, and oriented division of vascular endothelial cells. Further mechanistic studies demonstrate that IFT88 interacts with γ-tubulin and microtubule plus-end tracking proteins and promotes microtubule stability. Our findings indicate that IFT88 regulates angiogenesis through its actions in microtubule-based cellular processes, independent of its role in ciliogenesis.
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Affiliation(s)
- Yang Yang
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of the Ministry of Education, Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China; Department of Translational Medicine Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Miao Chen
- College of Life Sciences, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Institute of Biomedical Sciences, Shandong Normal University, Jinan 250014, China
| | - Jingrui Li
- College of Life Sciences, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Institute of Biomedical Sciences, Shandong Normal University, Jinan 250014, China
| | - Renjie Hong
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of the Ministry of Education, Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China
| | - Jia Yang
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of the Ministry of Education, Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China
| | - Fan Yu
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of the Ministry of Education, Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China
| | - Te Li
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of the Ministry of Education, Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China
| | - Song Yang
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of the Ministry of Education, Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China
| | - Jie Ran
- College of Life Sciences, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Institute of Biomedical Sciences, Shandong Normal University, Jinan 250014, China
| | - Chunyue Guo
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of the Ministry of Education, Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China
| | - Yi Zhao
- Department of Translational Medicine Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Yi Luan
- Department of Translational Medicine Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Min Liu
- College of Life Sciences, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Institute of Biomedical Sciences, Shandong Normal University, Jinan 250014, China
| | - Dengwen Li
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of the Ministry of Education, Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China
| | - Songbo Xie
- College of Life Sciences, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Institute of Biomedical Sciences, Shandong Normal University, Jinan 250014, China.
| | - Jun Zhou
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of the Ministry of Education, Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China; College of Life Sciences, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Institute of Biomedical Sciences, Shandong Normal University, Jinan 250014, China.
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24
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From observing to controlling: Inducible control of organelle dynamics and interactions. Curr Opin Cell Biol 2021; 71:69-76. [PMID: 33706236 DOI: 10.1016/j.ceb.2021.02.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/27/2021] [Accepted: 02/04/2021] [Indexed: 12/17/2022]
Abstract
The dynamics and interactions of cellular organelles underlie many aspects of cellular functioning. Until recently, assessment of organelle dynamics has been primarily observational or required whole-cell perturbations to assess the implications of altered organelle motility and positioning. However, thanks to recently developed and optimized intervention strategies, we now have the ability to control organelles in their unperturbed state, altering organelle positioning, membrane trafficking pathways, as well as organelle interactions. This can be performed both globally and locally, giving fine control over the range, reversibility, and extent of organelle dynamics. Here, we describe how these tools are currently used for controlling organelles and give insight into the exciting future of this emerging field.
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25
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Xie C, Martens JR. Potential Therapeutic Targets for Olfactory Dysfunction in Ciliopathies Beyond Single-Gene Replacement. Chem Senses 2021; 46:6159785. [PMID: 33690843 DOI: 10.1093/chemse/bjab010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Olfactory dysfunction is a common disorder in the general population. There are multiple causes, one of which being ciliopathies, an emerging class of human hereditary genetic disorders characterized by multiple symptoms due to defects in ciliary biogenesis, maintenance, and/or function. Mutations/deletions in a wide spectrum of ciliary genes have been identified to cause ciliopathies. Currently, besides symptomatic therapy, there is no available therapeutic treatment option for olfactory dysfunction caused by ciliopathies. Multiple studies have demonstrated that targeted gene replacement can restore the morphology and function of olfactory cilia in olfactory sensory neurons and further re-establish the odor-guided behaviors in animals. Therefore, targeted gene replacement could be potentially used to treat olfactory dysfunction in ciliopathies. However, due to the potential limitations of single-gene therapy for polygenic mutation-induced diseases, alternative therapeutic targets for broader curative measures need to be developed for olfactory dysfunction, and also for other symptoms in ciliopathies. Here we review the current understanding of ciliogenesis and maintenance of olfactory cilia. Furthermore, we emphasize signaling mechanisms that may be involved in the regulation of olfactory ciliary length and highlight potential alternative therapeutic targets for the treatment of ciliopathy-induced dysfunction in the olfactory system and even in other ciliated organ systems.
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Affiliation(s)
- Chao Xie
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, 1200 Newell Drive, Gainesville, FL 32610, USA.,Center for Smell and Taste, University of Florida College of Medicine, 1149 Newell Drive, Gainesville, FL 32610, USA
| | - Jeffrey R Martens
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, 1200 Newell Drive, Gainesville, FL 32610, USA.,Center for Smell and Taste, University of Florida College of Medicine, 1149 Newell Drive, Gainesville, FL 32610, USA
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26
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Gailey CD, Wang EJ, Jin L, Ahmadi S, Brautigan DL, Li X, Xu W, Scott MM, Fu Z. Phosphosite T674A mutation in kinesin family member 3A fails to reproduce tissue and ciliary defects characteristic of CILK1 loss of function. Dev Dyn 2021; 250:263-273. [PMID: 32935890 PMCID: PMC8460152 DOI: 10.1002/dvdy.252] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 09/10/2020] [Accepted: 09/11/2020] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Kinesin family member 3A (KIF3A) is a molecular motor protein in the heterotrimeric kinesin-2 complex that drives anterograde intraflagellar transport. This process plays a pivotal role in both biogenesis and maintenance of the primary cilium that supports tissue development. Ciliogenesis associated kinase 1 (CILK1) phosphorylates human KIF3A at Thr672. CILK1 loss of function causes ciliopathies that manifest profound and multiplex developmental defects, including hydrocephalus, polydactyly, shortened and hypoplastic bones and alveoli airspace deficiency, leading to perinatal lethality. Prior studies have raised the hypothesis that CILK1 phosphorylation of KIF3A is critical for its regulation of organ development. RESULTS We produced a mouse model with phosphorylation site Thr674 in mouse Kif3a mutated to Ala. Kif3a T674A homozygotes are viable and exhibit no skeletal and brain abnormalities, and only mildly reduced airspace in alveoli. Mouse embryonic fibroblasts carrying Kif3a T674A mutation show a normal rate of ciliation and a moderate increase in cilia length. CONCLUSION These results indicate that eliminating Kif3a Thr674 phosphorylation by Cilk1 is insufficient to reproduce the severe developmental defects in ciliopathies caused by Cilk1 loss of function. This suggests KIF3A-Thr672 phosphorylation by CILK1 is not essential for tissue development and other substrates are involved in CILK1 ciliopathies.
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Affiliation(s)
- Casey D. Gailey
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Eric J. Wang
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Li Jin
- Department of Orthopedic Surgery, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Sean Ahmadi
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia
| | - David L. Brautigan
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia
- NCI designated Cancer Center, Cancer Biology Program, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Xudong Li
- Department of Orthopedic Surgery, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Wenhao Xu
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Michael M. Scott
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Zheng Fu
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia
- NCI designated Cancer Center, Cancer Biology Program, University of Virginia School of Medicine, Charlottesville, Virginia
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27
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Quinn SM, Vargason T, Pokhrel N, Antony E, Hahn J, Gilbert SP. KIF3A accelerates KIF3C within the kinesin-2 heterodimer to generate symmetrical phosphate release rates for each processive step. J Biol Chem 2021; 296:100020. [PMID: 33144324 PMCID: PMC7948976 DOI: 10.1074/jbc.ra120.015272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/31/2020] [Accepted: 11/03/2020] [Indexed: 12/01/2022] Open
Abstract
Heterodimeric KIF3AC is a mammalian kinesin-2 that is highly expressed in the central nervous system and associated with vesicles in neurons. KIF3AC is an intriguing member of the kinesin-2 family because the intrinsic kinetics of KIF3A and KIF3C when expressed as homodimers and analyzed in vitro are distinctively different from each other. For example, the single-molecule velocities of the engineered homodimers KIF3AA and KIF3CC are 293 and 7.5 nm/s, respectively, whereas KIF3AC has a velocity of 186 nm/s. These results led us to hypothesize that heterodimerization alters the intrinsic catalytic properties of the two heads, and an earlier computational analysis predicted that processive steps would alternate between a fast step for KIF3A followed by a slow step for KIF3C resulting in asymmetric stepping. To test this hypothesis directly, we measured the presteady-state kinetics of phosphate release for KIF3AC, KIF3AA, and KIF3CC followed by computational modeling of the KIF3AC phosphate release transients. The results reveal that KIF3A and KIF3C retain their intrinsic ATP-binding and hydrolysis kinetics. Yet within KIF3AC, KIF3A activates the rate of phosphate release for KIF3C such that the coupled steps of phosphate release and dissociation from the microtubule become more similar for KIF3A and KIF3C. These coupled steps are the rate-limiting transition for the ATPase cycle suggesting that within KIF3AC, the stepping kinetics are similar for each head during the processive run. Future work will be directed to define how these properties enable KIF3AC to achieve its physiological functions.
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Affiliation(s)
- Sean M Quinn
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, New York, USA; Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Troy Vargason
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA; Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Nilisha Pokhrel
- The Department of Biology, Marquette University, Milwaukee, Wisconsin, USA
| | - Edwin Antony
- The Department of Biology, Marquette University, Milwaukee, Wisconsin, USA; The Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St Louis, Missouri, USA
| | - Juergen Hahn
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA; Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA; Department of Chemical & Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA.
| | - Susan P Gilbert
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, New York, USA; Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA.
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28
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Zhu X, Wang J, Li S, Lechtreck K, Pan J. IFT54 directly interacts with kinesin-II and IFT dynein to regulate anterograde intraflagellar transport. EMBO J 2020; 40:e105781. [PMID: 33368450 DOI: 10.15252/embj.2020105781] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 11/30/2020] [Accepted: 12/04/2020] [Indexed: 12/31/2022] Open
Abstract
The intraflagellar transport (IFT) machinery consists of the anterograde motor kinesin-II, the retrograde motor IFT dynein, and the IFT-A and -B complexes. However, the interaction among IFT motors and IFT complexes during IFT remains elusive. Here, we show that the IFT-B protein IFT54 interacts with both kinesin-II and IFT dynein and regulates anterograde IFT. Deletion of residues 342-356 of Chlamydomonas IFT54 resulted in diminished anterograde traffic of IFT and accumulation of IFT motors and complexes in the proximal region of cilia. IFT54 directly interacted with kinesin-II and this interaction was strengthened for the IFT54Δ342-356 mutant in vitro and in vivo. The deletion of residues 261-275 of IFT54 reduced ciliary entry and anterograde traffic of IFT dynein with accumulation of IFT complexes near the ciliary tip. IFT54 directly interacted with IFT dynein subunit D1bLIC, and deletion of residues 261-275 reduced this interaction. The interactions between IFT54 and the IFT motors were also observed in mammalian cells. Our data indicate a central role for IFT54 in binding the IFT motors during anterograde IFT.
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Affiliation(s)
- Xin Zhu
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong Province, China
| | - Jieling Wang
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Shufen Li
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Karl Lechtreck
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
| | - Junmin Pan
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong Province, China
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29
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van der Burght SN, Rademakers S, Johnson JL, Li C, Kremers GJ, Houtsmuller AB, Leroux MR, Jansen G. Ciliary Tip Signaling Compartment Is Formed and Maintained by Intraflagellar Transport. Curr Biol 2020; 30:4299-4306.e5. [DOI: 10.1016/j.cub.2020.08.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 07/13/2020] [Accepted: 08/07/2020] [Indexed: 02/07/2023]
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30
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Webb S, Mukhopadhyay AG, Roberts AJ. Intraflagellar transport trains and motors: Insights from structure. Semin Cell Dev Biol 2020; 107:82-90. [PMID: 32684327 PMCID: PMC7561706 DOI: 10.1016/j.semcdb.2020.05.021] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 05/19/2020] [Accepted: 05/26/2020] [Indexed: 11/17/2022]
Abstract
Intraflagellar transport (IFT) sculpts the proteome of cilia and flagella; the antenna-like organelles found on the surface of virtually all human cell types. By delivering proteins to the growing ciliary tip, recycling turnover products, and selectively transporting signalling molecules, IFT has critical roles in cilia biogenesis, quality control, and signal transduction. IFT involves long polymeric arrays, termed IFT trains, which move to and from the ciliary tip under the power of the microtubule-based motor proteins kinesin-II and dynein-2. Recent top-down and bottom-up structural biology approaches are converging on the molecular architecture of the IFT train machinery. Here we review these studies, with a focus on how kinesin-II and dynein-2 assemble, attach to IFT trains, and undergo precise regulation to mediate bidirectional transport.
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Affiliation(s)
- Stephanie Webb
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London, United Kingdom
| | - Aakash G Mukhopadhyay
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London, United Kingdom
| | - Anthony J Roberts
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London, United Kingdom.
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31
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Li S, Wan KY, Chen W, Tao H, Liang X, Pan J. Functional exploration of heterotrimeric kinesin-II in IFT and ciliary length control in Chlamydomonas. eLife 2020; 9:58868. [PMID: 33112235 PMCID: PMC7652414 DOI: 10.7554/elife.58868] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 10/28/2020] [Indexed: 12/27/2022] Open
Abstract
Heterodimeric motor organization of kinesin-II is essential for its function in anterograde IFT in ciliogenesis. However, the underlying mechanism is not well understood. In addition, the anterograde IFT velocity varies significantly in different organisms, but how this velocity affects ciliary length is not clear. We show that in Chlamydomonas motors are only stable as heterodimers in vivo, which is likely the key factor for the requirement of a heterodimer for IFT. Second, chimeric CrKinesin-II with human kinesin-II motor domains functioned in vitro and in vivo, leading to a ~ 2.8 fold reduced anterograde IFT velocity and a similar fold reduction in IFT injection rate that supposedly correlates with ciliary assembly activity. However, the ciliary length was only mildly reduced (~15%). Modeling analysis suggests a nonlinear scaling relationship between IFT velocity and ciliary length that can be accounted for by limitation of the motors and/or its ciliary cargoes, e.g. tubulin.
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Affiliation(s)
- Shufen Li
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Kirsty Y Wan
- Living Systems Institute, University of Exeter, Exeter, United Kingdom
| | - Wei Chen
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Hui Tao
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Xin Liang
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Junmin Pan
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
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32
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Nakayama K, Katoh Y. Architecture of the IFT ciliary trafficking machinery and interplay between its components. Crit Rev Biochem Mol Biol 2020; 55:179-196. [PMID: 32456460 DOI: 10.1080/10409238.2020.1768206] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Cilia and flagella serve as cellular antennae and propellers in various eukaryotic cells, and contain specific receptors and ion channels as well as components of axonemal microtubules and molecular motors to achieve their sensory and motile functions. Not only the bidirectional trafficking of specific proteins within cilia but also their selective entry and exit across the ciliary gate is mediated by the intraflagellar transport (IFT) machinery with the aid of motor proteins. The IFT-B complex, which is powered by the kinesin-2 motor, mediates anterograde protein trafficking from the base to the tip of cilia, whereas the IFT-A complex together with the dynein-2 complex mediates retrograde protein trafficking. The BBSome complex connects ciliary membrane proteins to the IFT machinery. Defects in any component of this trafficking machinery lead to abnormal ciliogenesis and ciliary functions, and results in a broad spectrum of disorders, collectively called the ciliopathies. In this review article, we provide an overview of the architectures of the components of the IFT machinery and their functional interplay in ciliary protein trafficking.
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Affiliation(s)
- Kazuhisa Nakayama
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Yohei Katoh
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
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33
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Wang EJ, Gailey CD, Brautigan DL, Fu Z. Functional Alterations in Ciliogenesis-Associated Kinase 1 (CILK1) that Result from Mutations Linked to Juvenile Myoclonic Epilepsy. Cells 2020; 9:E694. [PMID: 32178256 PMCID: PMC7140639 DOI: 10.3390/cells9030694] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 03/09/2020] [Accepted: 03/11/2020] [Indexed: 12/30/2022] Open
Abstract
Ciliopathies are a group of human genetic disorders associated with mutations that give rise to the dysfunction of primary cilia. Ciliogenesis-associated kinase 1 (CILK1), formerly known as intestinal cell kinase (ICK), is a conserved serine and threonine kinase that restricts primary (non-motile) cilia formation and length. Mutations in CILK1 are associated with ciliopathies and are also linked to juvenile myoclonic epilepsy (JME). However, the effects of the JME-related mutations in CILK1 on kinase activity and CILK1 function are unknown. Here, we report that JME pathogenic mutations in the CILK1 N-terminal kinase domain abolish kinase activity, evidenced by the loss of phosphorylation of kinesin family member 3A (KIF3A) at Thr672, while JME mutations in the C-terminal non-catalytic domain (CTD) have little effect on KIF3A phosphorylation. Although CILK1 variants in the CTD retain catalytic activity, they nonetheless lose the ability to restrict cilia length and also gain function in promoting ciliogenesis. We show that wild type CILK1 predominantly localizes to the base of the primary cilium; in contrast, JME variants of CILK1 are distributed along the entire axoneme of the primary cilium. These results demonstrate that JME pathogenic mutations perturb CILK1 function and intracellular localization. These CILK1 variants affect the primary cilium, independent of CILK1 phosphorylation of KIF3A. Our findings suggest that CILK1 mutations linked to JME result in alterations of primary cilia formation and homeostasis.
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Affiliation(s)
- Eric J. Wang
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA; (E.J.W.); (C.D.G.)
| | - Casey D. Gailey
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA; (E.J.W.); (C.D.G.)
| | - David L. Brautigan
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA;
- NCI-Designated Cancer Center, Cancer Biology Program, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Zheng Fu
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA; (E.J.W.); (C.D.G.)
- NCI-Designated Cancer Center, Cancer Biology Program, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
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34
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Zhao Q, Li S, Shao S, Wang Z, Pan J. FLS2 is a CDK-like kinase that directly binds IFT70 and is required for proper ciliary disassembly in Chlamydomonas. PLoS Genet 2020; 16:e1008561. [PMID: 32134924 PMCID: PMC7077844 DOI: 10.1371/journal.pgen.1008561] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 03/17/2020] [Accepted: 02/01/2020] [Indexed: 02/06/2023] Open
Abstract
Intraflagellar transport (IFT) is required for ciliary assembly and maintenance. While disruption of IFT may trigger ciliary disassembly, we show here that IFT mediated transport of a CDK-like kinase ensures proper ciliary disassembly. Mutations in flagellar shortening 2 (FLS2), encoding a CDK-like kinase, lead to retardation of cilia resorption and delay of cell cycle progression. Stimulation for ciliary disassembly induces gradual dephosphorylation of FLS2 accompanied with gradual inactivation. Loss of FLS2 or its kinase activity induces early onset of kinesin13 phosphorylation in cilia. FLS2 is predominantly localized in the cell body, however, it is transported to cilia upon induction of ciliary disassembly. FLS2 directly interacts with IFT70 and loss of this interaction inhibits its ciliary transport, leading to dysregulation of kinesin13 phosphorylation and retardation of ciliary disassembly. Thus, this work demonstrates that IFT plays active roles in controlling proper ciliary disassembly by transporting a protein kinase to cilia to regulate a microtubule depolymerizer. Cilia or eukaryotic flagella are cellular surface protrusions that function in cell motility as well as sensing. They are dynamic structures that undergo assembly and disassembly. Cilia are resorbed during cell cycle progression. Dysregulation of cilia resorption may cause delay of cell cycle progression, which underlies aberrant cell differentiation and even cancer. Ciliary resorption requires depolmerization of axonemal microtubules that is mediated by kinesin13. Using the unicellular green alga, Chlamydomonas, we have identified a CDK-like kinase FLS2 that when mutated retards cilia resorption, leading to delay of cell cycle progression. FLS2, a cell body protein, is transported to cilia via intraflagellar transport upon induction of cilia resorption. FLS2 directly interacts with IFT70 and loss of this interaction inhibits transport of FLS2 to cilia and fails to regulate proper phosphorylation of kinesin13 in cilia.
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Affiliation(s)
- Qin Zhao
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Shufen Li
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Shangjin Shao
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Zhengmao Wang
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Junmin Pan
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong Province, China
- * E-mail:
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35
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Deeb SK, Guzik-Lendrum S, Jeffrey JD, Gilbert SP. The ability of the kinesin-2 heterodimer KIF3AC to navigate microtubule networks is provided by the KIF3A motor domain. J Biol Chem 2019; 294:20070-20083. [PMID: 31748411 PMCID: PMC6937563 DOI: 10.1074/jbc.ra119.010725] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 11/17/2019] [Indexed: 01/13/2023] Open
Abstract
Heterodimeric kinesin family member KIF3AC is a mammalian kinesin-2 that is highly expressed in the central nervous system and has been implicated in intracellular transport. KIF3AC is unusual in that the motility characteristics of KIF3C when expressed as a homodimer are exceeding slow, whereas homodimeric KIF3AA, as well as KIF3AC, have much faster ATPase kinetics and single molecule velocities. Heterodimeric KIF3AC and homodimeric KIF3AA and KIF3CC are processive, although the run length of KIF3AC exceeds that of KIF3AA and KIF3CC. KIF3C is of particular interest because it exhibits a signature 25-residue insert of glycine and serine residues in loop L11 of its motor domain, and this insert is not present in any other kinesin, suggesting that it confers specific properties to mammalian heterodimeric KIF3AC. To gain a better understanding of the mechanochemical potential of KIF3AC, we pursued a single molecule study to characterize the navigation ability of KIF3AC, KIF3AA, and KIF3CC when encountering microtubule intersections. The results show that all three motors exhibited a preference to remain on the same microtubule when approaching an intersection from the top microtubule, and the majority of track switches occurred from the bottom microtubule onto the top microtubule. Heterodimeric KIF3AC and homodimeric KIF3AA displayed a similar likelihood of switching tracks (36.1 and 32.3%, respectively). In contrast, KIF3CC detached at intersections (67.7%) rather than switch tracks. These results indicate that it is the properties of KIF3A that contribute largely to the ability of KIF3AC to switch microtubule tracks to navigate intersections.
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Affiliation(s)
- Stephanie K Deeb
- Department of Biological Sciences and the Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180
| | - Stephanie Guzik-Lendrum
- Department of Biological Sciences and the Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180
| | - Jasper D Jeffrey
- Department of Biological Sciences and the Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180
| | - Susan P Gilbert
- Department of Biological Sciences and the Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180
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Fu Z, Gailey CD, Wang EJ, Brautigan DL. Ciliogenesis associated kinase 1: targets and functions in various organ systems. FEBS Lett 2019; 593:2990-3002. [PMID: 31506943 DOI: 10.1002/1873-3468.13600] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 08/22/2019] [Accepted: 09/04/2019] [Indexed: 12/12/2022]
Abstract
Ciliogenesis associated kinase 1 (CILK1) was previously known as intestinal cell kinase because it was cloned from that origin. However, CILK1 is now recognized as a widely expressed and highly conserved serine/threonine protein kinase. Mutations in the human CILK1 gene have been associated with ciliopathies, a group of human genetic disorders with defects in the primary cilium. In mice, both Cilk1 knock-out and Cilk1 knock-in mutations have recapitulated human ciliopathies. Thus, CILK1 has a fundamental role in the function of the cilium. Several candidate substrates have been proposed for CILK1 and the challenge is to relate these to the mutant phenotypes. In this review, we summarize what is known about CILK1 functions and targets, and discuss gaps in current knowledge that motivate further experimentation to fully understand the role of CILK1 in organ development in humans.
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Affiliation(s)
- Zheng Fu
- Department of Pharmacology, University of Virginia, Charlottesville, VA, USA
| | - Casey D Gailey
- Department of Pharmacology, University of Virginia, Charlottesville, VA, USA
| | - Eric J Wang
- Department of Pharmacology, University of Virginia, Charlottesville, VA, USA
| | - David L Brautigan
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA, USA
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Oh YS, Wang EJ, Gailey CD, Brautigan DL, Allen BL, Fu Z. Ciliopathy-Associated Protein Kinase ICK Requires Its Non-Catalytic Carboxyl-Terminal Domain for Regulation of Ciliogenesis. Cells 2019; 8:E677. [PMID: 31277411 PMCID: PMC6678984 DOI: 10.3390/cells8070677] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 07/01/2019] [Accepted: 07/02/2019] [Indexed: 01/08/2023] Open
Abstract
Loss-of-function mutations in the human ICK (intestinal cell kinase) gene cause dysfunctional primary cilia and perinatal lethality which are associated with human ciliopathies. The enzyme that we herein call CAPK (ciliopathy-associated protein kinase) is a serine/threonine protein kinase that has a highly conserved MAPK-like N-terminal catalytic domain and an unstructured C-terminal domain (CTD) whose functions are completely unknown. In this study, we demonstrate that truncation of the CTD impairs the ability of CAPK to interact with and phosphorylate its substrate, kinesin family member 3A (KIF3A). We also find that deletion of the CTD of CAPK compromises both localization to the primary cilium and negative regulation of ciliogenesis. Thus, CAPK substrate recognition, ciliary targeting, and ciliary function depend on the non-catalytic CTD of the protein which is predicted to be intrinsically disordered.
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Affiliation(s)
- Yoon Seon Oh
- Department of Pharmacology, University of Virginia Medical School, Charlottesville, VA 22908, USA
| | - Eric J Wang
- Department of Pharmacology, University of Virginia Medical School, Charlottesville, VA 22908, USA
| | - Casey D Gailey
- Department of Pharmacology, University of Virginia Medical School, Charlottesville, VA 22908, USA
| | - David L Brautigan
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia Medical School, Charlottesville, VA 22908, USA
- Center for Cell Signaling, University of Virginia Medical School, Charlottesville, VA 22908, USA
| | - Benjamin L Allen
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Zheng Fu
- Department of Pharmacology, University of Virginia Medical School, Charlottesville, VA 22908, USA.
- Center for Cell Signaling, University of Virginia Medical School, Charlottesville, VA 22908, USA.
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Mirvis M, Siemers KA, Nelson WJ, Stearns TP. Primary cilium loss in mammalian cells occurs predominantly by whole-cilium shedding. PLoS Biol 2019; 17:e3000381. [PMID: 31314751 PMCID: PMC6699714 DOI: 10.1371/journal.pbio.3000381] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 08/19/2019] [Accepted: 07/02/2019] [Indexed: 12/17/2022] Open
Abstract
The primary cilium is a central signaling hub in cell proliferation and differentiation and is built and disassembled every cell cycle in many animal cells. Disassembly is critically important, as misregulation or delay of cilia loss leads to cell cycle defects. The physical means by which cilia are lost are poorly understood but are thought to involve resorption of ciliary components into the cell body. To investigate cilium loss in mammalian cells, we used live-cell imaging to comprehensively characterize individual events. The predominant mode of cilium loss was rapid deciliation, in which the membrane and axoneme of the cilium was shed from the cell. Gradual resorption was also observed, as well as events in which a period of gradual resorption was followed by rapid deciliation. Deciliation resulted in intact shed cilia that could be recovered from culture medium and contained both membrane and axoneme proteins. We modulated levels of katanin and intracellular calcium, two putative regulators of deciliation, and found that excess katanin promotes cilia loss by deciliation, independently of calcium. Together, these results suggest that mammalian ciliary loss involves a tunable decision between deciliation and resorption.
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Affiliation(s)
- Mary Mirvis
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, United States of America
| | - Kathleen A. Siemers
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, United States of America
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - W. James Nelson
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, United States of America
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Tim P. Stearns
- Department of Biology, Stanford University, Stanford, California, United States of America
- Department of Genetics, Stanford University, Stanford, California, United States of America
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