Cilia are small, antenna-like structures on the surface of eukaryotic cells that harbor a unique set of sensory proteins, including GPCRs and other membrane proteins. The transport of these proteins involves the BBSome, an eight-membered protein complex that is recruited to ciliary membranes by the G-protein Arl6. BBSome malfunction leads to Bardet-Biedl syndrome, a ciliopathy with severe conse...

Bardet-Biedl syndrome (BBS) is an autosomal recessive ciliopathy with multisystem involvement. So far, 18 BBS genes have been identified and the majority of them are essential for the function of BBSome, a protein complex involved in transporting membrane proteins into and from cilia. Yet defects in the identified genes cannot account for all the BBS cases. The genetic heterogeneity of this dis...

Nephronophthisis is the most common genetic cause of end-stage renal failure during childhood and adolescence. Genetic studies have identified disease-causing mutations in at least 11 different genes (NPHP1-11), but the function of the corresponding nephrocystin proteins remains poorly understood. The two evolutionarily conserved proteins nephrocystin-1 (NPHP1) and nephrocystin-4 (NPHP4) intera...

Ciliopathies are pleiotropic and genetically heterogeneous disorders caused by defective development and function of the primary cilium. Bardet-Biedl syndrome (BBS) proteins localize to the base of cilia and undergo intraflagellar transport, and the loss of their functions leads to a multisystemic ciliopathy. Here we report the identification of mutations in guanylate cyclases (GCYs) as modifie...

Congenital skeletal anomalies are rare disorders, with a subset affecting both the cranial and appendicular skeleton. Two categories, craniosynostosis syndromes and chondrodysplasias, frequently result from aberrant regulation of the fibroblast growth factor (FGF) signaling pathway. Our recent work has implicated FGF signaling in a third category: ciliopathic skeletal dysplasias. In this work, ...

Cilia and flagella are highly conserved and important microtubule-based organelles that project from the surface of eukaryotic cells and act as antennae to sense extracellular signals. Moreover, cilia have emerged as key players in numerous physiological, developmental, and sensory processes such as hearing, olfaction, and photoreception. Genetic defects in ciliary proteins responsible for cili...

We describe two brothers with Joubert syndrome (JS). JS diagnosis was made on the basis of neurological findings and the presence of the characteristic "molar tooth sign", which was subsequently confirmed by magnetic resonance imaging. Both brothers demonstrated ptosis, hypotropia, exotropia, and horizontal pendular nystagmus. The younger brother had mild chorioretinal discoloration at the peri...

UNLABELLED A girl with polydactyly has had respiratory tract problems, including atelectasis, since birth. She has a high arched palate, a tongue hamartoma and dysmorphic face. Electron microscopy of nasal and bronchial brush biopsies repeatedly revealed centriole/basal body disarray and extreme sparseness of cilia. At the age of 2 years and 11 months, she displayed retardation of both motor an...

Primary cilia are microtubule structures that extend from the distal end of the mature, mother centriole. CEP164 is a component of the distal appendages carried by the mother centriole that is required for primary cilium formation. Recent data have implicated CEP164 as a ciliopathy gene and suggest that CEP164 plays some roles in the DNA damage response (DDR). We used reverse genetics to test t...

Phosphoinositides are lipids involved in the vesicular transport of proteins and lipids between the different compartments of eukaryotic cells. They act by recruiting and/or activating effector proteins and thus are involved in regulating various cellular functions, such as vesicular budding, membrane fusion and cytoskeleton dynamics. Although detected in small concentrations in membranes, thei...