Subcellular localization of CLIP-170/restin in immature and mature dendritic cells.

(Top row) In immature DCs, CLIP-170/restin appears in numerous large, submembranous and cytoplasmic patches predominantly beneath membrane ruffling sites (arrow). Moreover, in a large proportion of DCs, the protein occurs in thick and branching cytoplasmic bundles, a pattern previously reported exclusively for CLIP-170–cDNA-transfected cells that express very high amounts of the protein. Staining was performed using the CLIP-170/restin-specific monoclonal antibody 2D6 (green). Nuclei were visualized using PI (red). (Middle row) Double staining with 2D6 (red on the left) and microtubule antibodies (green in the middle) demonstrates that CLIP-170/restin aggregates colocalize preferentially with microtubule bundles, indicating the involvement of CLIP-170/restin in microtubule organization (right). (Bottom row) Maturation of DCs with different stimuli leads to dramatic reorganization of CLIP-170/restin with nearly exclusive submembranous localization and loss of centripetal cytoplasmic patches and bundles.