The functional interplay of Rab11, FIP3 and Rho proteins on the endosomal recycling pathway controls cell shape and symmetry

Jérôme Bouchet (1, 2) , Mary W. Mccaffrey (3) , Adrea Graziani (4) , Andrés Alcover (1)

1 Biologie Cellulaire des Lymphocytes - Lymphocyte Cell Biology
2 IC UM3 (UMR 8104 / U1016) - Institut Cochin
3 Molecular Cell Biology Laboratory
4 Università Vita e Salute

Several families of small GTPases regulate a variety of fundamental cellular processes, encompassing growth factor signal transduction, vesicular trafficking and control of the cytoskeleton. Frequently, their action is hierarchical and complementary, but much of the detail of their functional interactions remains to be clarified. It is well established that Rab family members regulate a variety of intracellular vesicle trafficking pathways. Moreover, Rho family GTPases are pivotal for the control of the actin and microtubule cytoskeleton. However, the interplay between these 2 types of GTPases has been rarely reported. We discuss here our recent findings showing that Rab11, a key regulator of endosomal recycling, and Rac1, a central actin cytoskeleton regulator involved in lamellipodium formation and cell migration, interplay on endosomes through the Rab11 effector FIP3. In the context of the rapidly reactive T lymphocytes, Rab11-Rac1 endosomal functional interplay is important to control cell shape changes and cell symmetry during lymphocyte spreading and immunological synapse formation and ultimately modulate T cell activation.

Domains: Adaptive immunology; Subcellular Processes [q-bio.SC]

Jérôme Bouchet, Mary W. Mccaffrey, Adrea Graziani, Andrés Alcover. The functional interplay of Rab11, FIP3 and Rho proteins on the endosomal recycling pathway controls cell shape and symmetry. Small GTPases, 2016, pp.1-6. ⟨10.1080/21541248.2016.1224288⟩. ⟨pasteur-01371033⟩