%0 Journal Article
%T Cilia develop long-lasting contacts, with other cilia
%A Peter K Jackson
%J Cilia
%D 2012
%I BioMed Central
%R 10.1186/2046-2530-1-5
%X Cilia are organized around the axoneme, with the centriole organizing the ciliary base [see [1,3], for reviews]. Around the axoneme, the ciliary membrane forms an extended sheath, organizing ciliary receptors and other membrane proteins. At the base of the cilium, the membrane typically shows an infolding or ciliary pocket, which can be a site for endocytosis. At the distal end of the cilium, the ciliary tip is a specialized segment of membrane that extends from the axoneme, and may serve a specialized function in signalling. The ciliary tip may also be a site where exosomes pinch off. A scanning electron microscopy study from the LaRusso lab observed exosomes in close apposition to cholangiocytes in ciliated bile ducts, and showed that isolated exosomes containing polycystin-1, -2, and fibrocystin can efficiently bind to cholangiocyte cilia [4,5]. The study suggested that membrane bound structures can associate with the ciliary membrane, and that specific paracrine effects of exosomes might be mediated by binding to cilia. A study from the Kernan lab in chordotonal organs of Drosophila suggested that a specialized ciliary diliation, a narrowing of the cilia, was organized by the intraflagellar transport (IFT-A) complex, and this ciliary specialization interacted with supporting cells in the chordotonal organ and was required for sensory function [6]. Finally, a number of studies show that the distal end of the retinal outer segment is in close juxtaposition to invaginations in retinal pigment epithelial cells (RPE), and that sloughing of outer segments triggers local phagocytosis by the RPE [7]. Finally, in Chylamydomonas induced to mating, the cilia can form agglutination structures critical to their mating function [8].So cilia appear to interact purposefully with cells and exosomes from their surrounding cellular neighbourhood. But what about touching each other?Lippincott-Schwartz and colleagues consider cilia-cilia pairing, first looking into the retina and li
%U http://www.ciliajournal.com/content/1/1/5