The more we know, the more we have to discover: an exciting future for understanding cilia and ciliopathies

Abstract

The Cilia 2014 conference was organised by four European networks: the Ciliopathy Alliance, the Groupement de Recherche CIL, the Nordic Cilia and Centrosome Network and the EU FP7 programme SYSCILIA. More than 400 delegates from 27 countries gathered at the Institut Pasteur conference centre in Paris, including 30 patients and patient representatives. The meeting offered a unique opportunity for exchange between different scientific and medical communities. Major highlights included new discoveries about the roles of motile and immotile cilia during development and homeostasis, the mechanism of cilium construction, as well as progress in diagnosis and possible treatment of ciliopathies. The contributions to the cilia field of flagellated infectious eukaryotes and of systems biology were also presented.

Keywords: Basal bodies; Centrioles; Cilia; Ciliopathies; Development; Flagella; Hedgehog; Intraflagellar; Signalling; Transport.

Figure 1

Scanning electron micrographs of an early mouse embryo, with three somite pairs, viewed from the posterior. (A) The node (white arrow) is clearly visible as a depression with a rounded posterior that continues forward opening out into the notochord. The cells surrounding the top of the node are often called the crown cells, and these have been implicated in responding to leftward nodal flow. Left (L) and right (R) sides are indicated. (B) A higher magnification of the node shown in panel (A). At this magnification, the presence of a single cilium on each of the cells within the pit of the node is visible. These cilia beat in a circular manner, but due to a posterior tilt, they drive a leftward flow of fluid in the node. It is this leftward nodal flow that normally establishes the direction of the left-right axis (credit: Dominic Norris).

Figure 2

The primary cilium. Scanning electron micrograph of the buccopharyngeal epithelium of E9.5 mouse embryo, showing a central primary cilium emerging from the apical surface surrounded by microvilli (credit: Christine Laclef).

Figure 3

Example of signalling at the primary cilium. (A) TGFβ/BMP signalling at the primary cilium. (B) TGFβ-RI (green) and P-smad2/3 (red) are recruited at the base of the primary cilium (blue) in TGFβ1-stimulated human foreskin fibroblasts (credit: [17]).

Figure 4

Example of protein dynamics at the cilium. A centriolar satellite protein (green) re-localises upon activation of an innate immune response in ciliated (red) RPE-cells. A. Unstimulated cell. B. Stimulated cell (Credit: Jens Andersen).