The DISC1-Girdin complex: a missing link in signaling to the T cell cytoskeleton

Abstract

In this study, using Jurkat cells, we show that DISC1 (Disrupted in Schizophrenia 1), and Girdin (Girders of actin filaments) are essential for typical actin accumulation at the immunological synapse. Furthermore, DISC1, Girdin, and dynein are bound in a complex. While initially this complex is seen as a central patch at the synapse, it relocates to a peripheral ring corresponding to the pSMAC. In the absence of DISC1, actin accumulation at the synapse is disrupted while dynein and the dynein-binding protein NDE1 fail to reorganize to the pSMAC. A similar effect is seen when Girdin is deleted. When cells are treated with inhibitors of actin polymerization, the dynein-NDE1 complex is lost from the synapse and the MTOC fails to translocate, suggesting that actin and dynein may be linked. Upon TCR stimulation, DISC1 becomes associated with talin which likely explains why the dynein complex colocalizes with the pSMAC. These results show that DISC1-Girdin regulates actin accumulation, cell spreading, and the distribution of the dynein complex at the synapse.