Phase separation of signaling molecules promotes T cell receptor signal transduction

Author Posting. © The Author(s), 2016. This is the author's version of the work. It is posted here by permission of American Association for the Advancement of Science for personal use, not for redistribution. The definitive version was published in Science 352 (2016): 595-599, doi:10.1126/science.aad9964.Activation of various cell surface receptors triggers the reorganization of downstream signaling molecules into micron- or submicron-sized clusters. However, the functional consequences of such clustering has been unclear. We biochemically reconstituted a 12-component signaling pathway on model membranes, beginning with T cell receptor (TCR) activation and ending with actin assembly. When TCR phoshophorylation was triggered, downstream signaling proteins spontaneously separated into liquid-like clusters that promoted signaling outputs both in vitro and in human Jurkat T cells. Reconstituted clusters were enriched in kinases but excluded phosphatases, and enhanced actin filament assembly by recruiting and organizing actin regulators. These results demonstrate that protein phase separation can create a distinct physical and biochemical compartment that facilitates signaling.This work was supported by the HCIA program of HHMI, the NIH (R01-GM56322 to M.K.R.) and Welch Foundation (I–1544 to M.K.R.). X.S. was supported by CRI Irvington postdoctoral fellowship. J.A.D. was supported by NRSA F32 award 5-F32-DK101188. E.H. was supported as a fellow of the Leukemia and Lymphoma Society. J.O. was supported by funds from Tobacco-Related Disease Research Program of the University of California (19FT-0090).2016-10-0