Leukocyte migration and trafficking is dynamically regulated by various chemokine and adhesion molecules and is vital to the proper function of the immune system. We describe a role for the Cas and Hef-1-associated signal transducer in hematopoietic cells (Chat-H) as a critical regulator of T lymphocyte migration, by using lentivirus-mediated RNA interference (RNAi). Impaired migration of Chat-H-depleted cells coincided with defective inside-out signaling shown by diminished chemokine-induced activation of the Rap-1 GTPase and integrin-mediated adhesion. Localization of Chat-H to the plasma membrane, association with its binding partner Crk-associated substrate in lymphocytes (CasL), and Chat-H-mediated CasL serine-threonine phosphorylation were required for T cell migration. These results identify Chat-H as a critical signaling intermediate acting upstream of Rap1 to regulate chemokine-induced adhesion and migration. © 2006 Elsevier Inc. All rights reserved.
Regelmann, A. G., Danzl, N. M., Wanjalla, C., & Alexandropoulos, K. (2006). The Hematopoietic Isoform of Cas-Hef1-Associated Signal Transducer Regulates Chemokine-Induced Inside-Out Signaling and T Cell Trafficking. Immunity, 25(6), 907–918. https://doi.org/10.1016/j.immuni.2006.09.014