Search results for "CILIOGENESIS"
showing 10 items of 39 documents
A high-throughput genome-wide siRNA screen for ciliogenesis identifies new ciliary functional components and ciliopathy genes.
2015
Defects in primary cilium biogenesis underlie the ciliopathies, a growing group of genetic disorders. We describe the first whole genome siRNA-based reverse genetics screen for defects in biogenesis and/or maintenance of the primary cilium, obtaining a global resource for investigation and interventions into the processes that are critical for the ciliary system. In total, we identified 83 candidate ciliogenesis and ciliopathy genes, including 15 components of the ubiquitin-proteasome system. The validated hits also include 12 encoding G-protein-coupled receptors, and three encoding pre-mRNA processing factors (PRPF6, PRPF8 and PRPF31) mutated in autosomal dominant retinitis pigmentosa. Com…
Mutations in KIAA0586 Cause Lethal Ciliopathies Ranging from a Hydrolethalus Phenotype to Short-Rib Polydactyly Syndrome
2015
KIAA0586, the human ortholog of chicken TALPID3, is a centrosomal protein that is essential for primary ciliogenesis. Its disruption in animal models causes defects attributed to abnormal hedgehog signaling; these defects include polydactyly and abnormal dorsoventral patterning of the neural tube. Here, we report homozygous mutations of KIAA0586 in four families affected by lethal ciliopathies ranging from a hydrolethalus phenotype to short-rib polydactyly. We show defective ciliogenesis, as well as abnormal response to SHH-signaling activation in cells derived from affected individuals, consistent with a role of KIAA0586 in primary cilia biogenesis. Whereas centriolar maturation seemed una…
Dynamic Changes in Ultrastructure of the Primary Cilium in Migrating Neuroblasts in the Postnatal Brain
2019
New neurons, referred to as neuroblasts, are continuously generated in the ventricular-subventricular zone of the brain throughout an animal's life. These neuroblasts are characterized by their unique potential for proliferation, formation of chain-like cell aggregates, and long-distance and high-speed migration through the rostral migratory stream (RMS) toward the olfactory bulb (OB), where they decelerate and differentiate into mature interneurons. The dynamic changes of ultrastructural features in postnatal-born neuroblasts during migration are not yet fully understood. Here we report the presence of a primary cilium, and its ultrastructural morphology and spatiotemporal dynamics, in mig…
Mutation ofPOC1Bin a Severe Syndromic Retinal Ciliopathy
2014
We describe a consanguineous Iraqi family with Leber congenital amaurosis (LCA), Joubert syndrome (JBTS), and polycystic kidney disease (PKD). Targeted next-generation sequencing for excluding mutations in known LCA and JBTS genes, homozygosity mapping, and whole-exome sequencing identified a homozygous missense variant, c.317G>C (p.Arg106Pro), in POC1B, a gene essential for ciliogenesis, basal body, and centrosome integrity. In silico modeling suggested a requirement of p.Arg106 for the formation of the third WD40 repeat and a protein interaction interface. In human and mouse retina, POC1B localized to the basal body and centriole adjacent to the connecting cilium of photoreceptors and in …
Germline deletion of Cetn1 causes infertility in male mice
2013
Centrins are calmodulin-like Ca2+-binding proteins that can be found in all ciliated eukaryotic cells from yeast to mammals. Expressed in male germ cells and photoreceptors, centrin 1 (CETN1) resides in the photoreceptor transition zone and connecting cilium. To identify its function in mammals, we deleted Cetn1 by homologous recombination. Cetn1−/− mice were viable and showed no sign of retina degeneration suggesting that CETN1 is nonessential for photoreceptor ciliogenesis or structural maintenance. Phototransduction components localized normally to the Cetn1−/− photoreceptor outer segments, and loss of CETN1 had no effect on light-induced translocation of transducin to the inner segment.…
Intraflagellar transport proteins in ciliogenesis of photoreceptor cells
2011
Background information. The assembly and maintenance of cilia depend on IFT (intraflagellar transport) mediated by molecular motors and their interplay with IFT proteins. Here, we have analysed the involvement of IFT proteins in the ciliogenesis of mammalian photoreceptor cilia. Results. Electron microscopy revealed that ciliogenesis in mouse photoreceptor cells follows an intracellular ciliogenesis pathway, divided into six distinct stages. The first stages are characterized by electron-dense centriolar satellites and a ciliary vesicle, whereas the formations of the ciliary shaft and the light-sensitive outer segment discs are features of the later stages. IFT proteins were associated with…
An siRNA-based functional genomics screen for the identification of regulators of ciliogenesis and ciliopathy genes
2015
Item does not contain fulltext Defects in primary cilium biogenesis underlie the ciliopathies, a growing group of genetic disorders. We describe a whole-genome siRNA-based reverse genetics screen for defects in biogenesis and/or maintenance of the primary cilium, obtaining a global resource. We identify 112 candidate ciliogenesis and ciliopathy genes, including 44 components of the ubiquitin-proteasome system, 12 G-protein-coupled receptors, and 3 pre-mRNA processing factors (PRPF6, PRPF8 and PRPF31) mutated in autosomal dominant retinitis pigmentosa. The PRPFs localize to the connecting cilium, and PRPF8- and PRPF31-mutated cells have ciliary defects. Combining the screen with exome sequen…
Phylogenetic profiling and cellular analyses of ARL16 reveal roles in traffic of IFT140 and INPP5E
2021
ABSTRACTThe ARF family of regulatory GTPases is ancient, with 16 members predicted to have been present in the last eukaryotic common ancestor. Our phylogenetic profiling of paralogs in diverse species identified four family members whose presence correlates with that of a cilium/flagellum: ARL3, ARL6, ARL13, and ARL16. No prior evidence links ARL16 to cilia or other cell functions, despite its presence throughout eukaryotes. Deletion of ARL16 in MEFs results in decreased ciliogenesis yet increased ciliary length. We also found Arl16 KO in MEFs to alter ciliary protein content, including loss of ARL13B, ARL3, INPP5E, and the IFT-A core component IFT140. Instead, both INPP5E and IFT140 accum…
An organelle-specific protein landscape identifies novel diseases and molecular mechanisms.
2016
Cellular organelles provide opportunities to relate biological mechanisms to disease. Here we use affinity proteomics, genetics and cell biology to interrogate cilia: poorly understood organelles, where defects cause genetic diseases. Two hundred and seventeen tagged human ciliary proteins create a final landscape of 1,319 proteins, 4,905 interactions and 52 complexes. Reverse tagging, repetition of purifications and statistical analyses, produce a high-resolution network that reveals organelle-specific interactions and complexes not apparent in larger studies, and links vesicle transport, the cytoskeleton, signalling and ubiquitination to ciliary signalling and proteostasis. We observe sub…
Chronological expression of Ciliated Bronchial Epithelium 1 during pulmonary development
2009
Ciliated Bronchial Epithelium (CBE) 1 is a novel gene, which is expressed in ciliated cells. As cilia are important during embryogenesis, the present authors characterised the murine homologue of CBE1 (Cbe1) and compared its temporal expression during murine and human lung development. Cbe1 cDNA was cloned and characterised using sequencing, standard PCR and Western blotting. Mouse and human embryonic/fetal lungs (HELs) were harvested for mRNA analysis and protein localisation in vivo and in vitro using RT-PCR and immunohistochemistry. The Cbe1 amino acid sequence was >75% identical with CBE1 and its alternative splicing and tissue distribution were highly conserved. Pulmonary expression of…