Molecular characterization of post-translational modifications of DUSP12 in T cells

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Presentation Time: 03:15 PM - 04:30 PM
Poster Board Number: B620
Abstract ID: 5376

Presenting Author:
Chia-Yu Yang , associate professor at Chang Gung Univ.

Abstract:

Dual-specificity phosphatase 12 (DUSP12) belongs to a family of DUSP protein phosphatases (DUSPs) that are associated with cell cycle regulation, insulin sensitivity, and Toll-like receptor signaling. It has been reported that protein expression and phosphatase activity of DUSPs are regulated by post-translational modifications that may be mediated through phosphorylation, ubiquitination, or methylation. However, the functional roles of post-translational modifications on DUSP12 in T cells remain unclear. Our results showed that DUSP12 expression was increased upon T cell receptor (TCR) signaling. The number of T cells was decreased in DUSP12-deficient mice. To study the upstream regulators of DUSP12 in T cells, we used a proteomics approach to identify the potential post-translational modifications on DUSP12 protein. Our result showed that DUSP12 may be ubiquitinated, and we also identified multiple ubiquitination sites on DUSP12. Using DUSP12 co-immunoprecipitation and liquid chromatography-mass spectrometry experiment, we have identified a novel E3 ligase as a DUSP12-binding protein, which may regulate T-cell activation. Furthermore, the effects of ubiquitination in regulating the activity and expression of DUSP12 in T cells upon T cell receptor signaling were explored. Our study reveals the molecular regulation of DUSP12 in T-cell activation and immune responses.