Wdr47, Camsaps, and Katanin cooperate to generate ciliary central microtubules

AbstractThe axonemal central pair (CP) are non-centrosomal microtubules critical for planar ciliary beat. How they form, however, is poorly understood. Here, we show that mammalian CP formation requires Wdr47, Camsaps, and microtubule-severing activity of Katanin. Katanin severs peripheral microtubules to produce central microtubule seeds in nascent cilia. Camsaps stabilize minus ends of the seeds to facilitate microtubule outgrowth, whereas Wdr47 concentrates Camsaps into the axonemal central lumen to properly position central microtubules. Wdr47 deficiency in mouse multicilia results in complete loss of CP, rotatory beat, and primary ciliary dyskinesia. Overexpression of Camsaps or their microtubule-binding regions induces central microtubules in Wdr47−/− ependymal cells but at the expense of low efficiency, abnormal numbers, and wrong location. Katanin levels and activity also impact the central microtubule number. We propose that Wdr47, Camsaps, and Katanin function together for the generation of non-centrosomal microtubule arrays in polarized subcellular compartments.

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Wdr47, Camsaps, and Katanin cooperate to generate ciliary central microtubules

10.21203/rs.3.rs-40777/v1 ◽

2020 ◽

Author(s):

Hao Liu ◽

Jianqun Zheng ◽

Lei Zhu ◽

Yawen Chen ◽

Yirong Zhang ◽

...

Keyword(s):

Primary Ciliary Dyskinesia ◽

Cooperative Work ◽

Complete Loss ◽

Ependymal Cells ◽

Work Team ◽

Central Pair ◽

Central Lumen ◽

Subcellular Compartments ◽

Low Efficiency ◽

Ciliary Dyskinesia

Abstract The axonemal central pair (CP) are non-centrosomal microtubules critical for planar ciliary beat. How they form, however, is poorly understood. Here, we show that mammalian CP formation requires cooperative activities of Katanin, Camsaps, and Wdr47. Katanin severs peripheral microtubules to produce central microtubule seeds in nascent cilia. Camsaps stabilize minus ends of the seeds to facilitate MT outgrowth, whereas Wdr47 concentrates Camsaps into the axonemal central lumen to properly position the central microtubules. Wdr47 deficiency in mouse multicilia results in complete loss of CP, rotatory beat, and primary ciliary dyskinesia. Overexpression of Camsaps induces central microtubules in Wdr47-/- ependymal cells but at the expense of low efficiency, abnormal numbers, and wrong location, whereas overexpression of a dominant inhibitor of Katanin impairs the CP formation. We propose that Wdr47, Camsaps, and Katanin constitute a general cooperative work team for the generation of non-centrosomal MT arrays in polarized subcellular compartments.

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Pcdp1 is a central apparatus protein that binds Ca2+-calmodulin and regulates ciliary motility

The Journal of Cell Biology ◽

10.1083/jcb.200912009 ◽

2010 ◽

Vol 189 (3) ◽

pp. 601-612 ◽

Cited By ~ 64

Author(s):

Christen G. DiPetrillo ◽

Elizabeth F. Smith

Keyword(s):

Primary Ciliary Dyskinesia ◽

Calcium Concentration ◽

Beat Frequency ◽

Calcium Sensor ◽

Central Pair ◽

Ciliary Motility ◽

Significant Impairment ◽

Central Apparatus ◽

Cilia And Flagella ◽

Ciliary Dyskinesia

For all motile eukaryotic cilia and flagella, beating is regulated by changes in intraciliary calcium concentration. Although the mechanism for calcium regulation is not understood, numerous studies have shown that calmodulin (CaM) is a key axonemal calcium sensor. Using anti-CaM antibodies and Chlamydomonas reinhardtii axonemal extracts, we precipitated a complex that includes four polypeptides and that specifically interacts with CaM in high [Ca2+]. One of the complex members, FAP221, is an orthologue of mammalian Pcdp1 (primary ciliary dyskinesia protein 1). Both FAP221 and mammalian Pcdp1 specifically bind CaM in high [Ca2+]. Reduced expression of Pcdp1 complex members in C. reinhardtii results in failure of the C1d central pair projection to assemble and significant impairment of motility including uncoordinated bends, severely reduced beat frequency, and altered waveforms. These combined results reveal that the central pair Pcdp1 (FAP221) complex is essential for control of ciliary motility.

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Novel genetic defects in primary ciliary dyskinesia affecting function of dynein arms and central pair apparatus

Cilia ◽

10.1186/2046-2530-1-s1-o1 ◽

2012 ◽

Vol 1 (S1) ◽

Author(s):

H Omran

Keyword(s):

Primary Ciliary Dyskinesia ◽

Genetic Defects ◽

Central Pair ◽

Dynein Arms ◽

Ciliary Dyskinesia

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Mutation of serine/threonine protein kinase 36 ( STK36 ) causes primary ciliary dyskinesia with a central pair defect

Human Mutation ◽

10.1002/humu.23261 ◽

2017 ◽

Vol 38 (8) ◽

pp. 964-969 ◽

Cited By ~ 33

Author(s):

Christine Edelbusch ◽

Sandra Cindrić ◽

Gerard W. Dougherty ◽

Niki T. Loges ◽

Heike Olbrich ◽

...

Keyword(s):

Protein Kinase ◽

Primary Ciliary Dyskinesia ◽

Central Pair ◽

Pair Defect ◽

Ciliary Dyskinesia

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A novel hypomorphic allele of Spag17 causes primary ciliary dyskinesia phenotypes in mice

Disease Models & Mechanisms ◽

10.1242/dmm.045344 ◽

2020 ◽

Vol 13 (10) ◽

pp. dmm045344

Author(s):

Zakia Abdelhamed ◽

Marshall Lukacs ◽

Sandra Cindric ◽

Heymut Omran ◽

Rolf W. Stottmann

Keyword(s):

Cerebrospinal Fluid ◽

Fluid Flow ◽

Primary Ciliary Dyskinesia ◽

Human Condition ◽

Central Pair ◽

Cerebrospinal Fluid Flow ◽

Hypomorphic Allele ◽

Motile Cilia ◽

The Brain ◽

Ciliary Dyskinesia

ABSTRACTPrimary ciliary dyskinesia (PCD) is a human condition of dysfunctional motile cilia characterized by recurrent lung infection, infertility, organ laterality defects and partially penetrant hydrocephalus. We recovered a mouse mutant from a forward genetic screen that developed many of the hallmark phenotypes of PCD. Whole-exome sequencing identified this primary ciliary dyskinesia only (Pcdo) allele to be a nonsense mutation (c.5236A>T) in the Spag17 coding sequence creating a premature stop codon (K1746*). The Pcdo variant abolished several isoforms of SPAG17 in the Pcdo mutant testis but not in the brain. Our data indicate differential requirements for SPAG17 in different types of motile cilia. SPAG17 is essential for proper development of the sperm flagellum and is required for either development or stability of the C1 microtubule structure within the central pair apparatus of the respiratory motile cilia, but not the brain ependymal cilia. We identified changes in ependymal ciliary beating frequency, but these did not appear to alter lateral ventricle cerebrospinal fluid flow. Aqueductal stenosis resulted in significantly slower and abnormally directed cerebrospinal fluid flow, and we suggest that this is the root cause of the hydrocephalus. The Spag17Pcdo homozygous mutant mice are generally viable to adulthood but have a significantly shortened lifespan, with chronic morbidity. Our data indicate that the c.5236A>T Pcdo variant is a hypomorphic allele of Spag17 that causes phenotypes related to motile, but not primary, cilia. Spag17Pcdo is a useful new model for elucidating the molecular mechanisms underlying central pair PCD pathogenesis in the mouse.This article has an associated First Person interview with the first author of the paper.

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Primary Ciliary Dyskinesia in Mice Lacking the Novel Ciliary Protein Pcdp1

Molecular and Cellular Biology ◽

10.1128/mcb.00354-07 ◽

2007 ◽

Vol 28 (3) ◽

pp. 949-957 ◽

Cited By ~ 76

Author(s):

Lance Lee ◽

Dean R. Campagna ◽

Jack L. Pinkus ◽

Howard Mulhern ◽

Todd A. Wyatt ◽

...

Keyword(s):

Epithelial Cells ◽

Male Infertility ◽

Primary Ciliary Dyskinesia ◽

Single Gene ◽

Ependymal Cells ◽

The Novel ◽

Gene Encoding ◽

Respiratory Epithelial ◽

Ciliated Epithelial Cells ◽

Ciliary Dyskinesia

ABSTRACT Primary ciliary dyskinesia (PCD) results from ciliary dysfunction and is commonly characterized by sinusitis, male infertility, hydrocephalus, and situs inversus. Mice homozygous for the nm1054 mutation develop phenotypes associated with PCD. On certain genetic backgrounds, homozygous mutants die perinatally from severe hydrocephalus, while mice on other backgrounds have an accumulation of mucus in the sinus cavity and male infertility. Mutant sperm lack mature flagella, while respiratory epithelial cilia are present but beat at a slower frequency than wild-type cilia. Transgenic rescue demonstrates that the PCD in nm1054 mutants results from the loss of a single gene encoding the novel primary ciliary dyskinesia protein 1 (Pcdp1). The Pcdp1 gene is expressed in spermatogenic cells and motile ciliated epithelial cells. Immunohistochemistry shows that Pcdp1 protein localizes to sperm flagella and the cilia of respiratory epithelial cells and brain ependymal cells in both mice and humans. This study demonstrates that Pcdp1 plays an important role in ciliary and flagellar biogenesis and motility, making the nm1054 mutant a useful model for studying the molecular genetics and pathogenesis of PCD.

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