title: The Rab GTPase Rab8 as a shared regulator of ciliogenesis and immune synapse assembly: From a conserved pathway to diverse cellular structures.
abstract: Rab GTPases, which form the largest branch of the Ras GTPase superfamily, regulate almost every step of vesicle-mediated trafficking. Among them, Rab8 is an essential participant in primary cilium formation. In a report recently published in the Journal of Cell Science, Finetti and colleagues identify Rab8 as a novel player in vesicular traffic in the non-ciliated T lymphocytes, which contributes to the assembly of the specialized signaling platform known as the immune synapse. By interacting with the v-SNARE VAMP-3, Rab8 is indeed responsible for the final docking/fusion step in T cell receptor (TCR) recycling to the immune synapse. A second important take-home message which comes to light from this work is that VAMP-3 also interacts with Rab8 at the base of the cilium in NIH-3T3 cells, where it regulates ciliary growth and targeting of Smoothened at the plasma membrane. Hence the data presented in this report, in addition to identifying Rab8 as a novel player in vesicular traffic to the immune synapse, reveal how both ciliated and non-ciliated cells take advantage of a conserved pathway to build highly specific cellular structures.
authors.affiliation: a Department of Life Sciences , University of Siena , Siena , Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Patrussi
authors.affiliation: a Department of Life Sciences , University of Siena , Siena , Italy.
authors.forename: Cosima T
authors.initials: CT
authors.lastname: Baldari
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D002923:Cilia / Q000378:metabolism*; D011992:Endosomes / Q000378:metabolism*; D054992:Immunological Synapses / Q000378:metabolism*; D051379:Mice; D041681:NIH 3T3 Cells; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism; D015398:Signal Transduction; D000072086:Smoothened Receptor / Q000378:metabolism; D051040:Vesicle-Associated Membrane Protein 3 / Q000378:metabolism; D020691:rab GTP-Binding Proteins / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; C514104:Ift20 protein, mouse; C521976:Rab8 protein, mouse; D011948:Receptors, Antigen, T-Cell; C491022:Smo protein, mouse; D000072086:Smoothened Receptor; D051040:Vesicle-Associated Membrane Protein 3; C494953:vesicle-associated membrane protein 3, mouse; D020691:rab GTP-Binding Proteins
keywords: GTPase; Rab8; TCR; immune synapse; primary cilium; receptor recycling