Cilia are microtubule-based cellular protrusions, and there are two types – motile and non-motile. Non-motile, or “primary,” cilia function in sensory reception and signaling. This signaling role of primary cilia means that signaling receptors must be sorted to their elongated plasma membrane. A recent paper shows the ability of a complex of proteins called the BBSome to assemble a coat complex that can transport and sort membrane proteins to cilia. Image above is of artificial vesicles called liposomes mixed with members of the BBSome, and the arrowheads are pointing to surfaces coated with the BBSome complex.
Reference: Hua Jin, Susan Roehl White, Toshinobu Shida, Stefan Schulz, Mike Aguiar, Steven P. Gygi, J. Fernando Bazan and Maxence V. Nachury. Cell 141, 1208-1219. ©2010 Elsevier Ltd. All rights reserved. Paper can be found here.