PTPN22 interacts with EB1 to regulate T cell receptor signaling

Abstract

PTPN22 has been reported as an important negative regulator of T cell signaling. Here we identified EB1 as an associated protein of PTPN22 via 2-hybrid and mass spectrometry screening.\n\nRecently the phosphorylation of EB1 has been proved in the regulation of T cell receptor (TCR) mediated signaling pathway. Our results shown that PTPN22 interacted with EB1 through the P1 domain of PTPN22, and regulated the Y247 phosphorylation site of EB1. The subsequent results suggest that PTPN22 interacts with EB1 and regulate the phosphorylation of EB1, which results in the regulation of the expression of T cell activation markers of CD25 and CD69, and the phosphorylation levels of the T cell signaling molecules, such as ZAP-70, LAT and Erk, ultimately resulting in NFAT transcription factors entering the nucleus and regulating the secretion of cytokine IL-2. This newly identified interaction between PTPN22 and EB1 may play an important role in TCR signal pathways.