Journal: iScience
Article Title: The dual specificity phosphatase 2 act as distal regulatory node in T cell signaling
doi: 10.1016/j.isci.2026.116690
Figure Lengend Snippet: DUSP2 dephoshorylates the MAP kinases ERK1/2, p38 MAPK, and JNK but not STAT3 in T cells (A)Western blot of Jurkat cells either left untreated or pretreated with CHX (10 μg/mL for 30 min) prior to activation with 5 μg/mL aCD3 and 10 nM PMA. Cell extracts were collected at indicated time points and western blots were probed with the antibodies detecting phosphorylated MAP kinases. (B) Relative mRNA expression levels of the inducible DUSPs (DUSP1, 2, 4, 5) in Jurkat cells unstimulated or stimulated for 2 h or 4 h with 250 ng/mL aCD3/and 250 ng/mL PMA ( n = 3). (C) RT-qPCR analysis was conducted to verify the induction of DUSP2 mRNA expression in Jurkat WT cells within 6 h after stimulation with 5 μg/mL aCD3 and 10 nM PMA or (D) within 4 h after stimulation with aCD3/aCD28 coated beads. Data are presented as DUSP2 mRNA expression normalized to geometric mean of GAPDH and TBP as control ( n = 3). (E) Western blot analysis of stimulated (5 μg/mL aCD3/10 nM PMA) Jurkat cells showed an inverse correlation of DUSP2 protein levels with MAPK phosphorylation levels after initial induction. (F) DUSP2 KO led to sustained MAPK phosphorylation after stimulation. (G) The rescue of Jurkat DUSP2 KO cells with wild-type DUSP2 (DUSP2 resWT ) restored the DUSP2 phosphatase function completely. This effect was abrogated in Jurkat cells (H) rescued with DUSP2 resKIM or (I) with DUSP2 resCS mutants. (J) Stimulation (5 μg/mL aCD3/10 nM PMA) of doxycycline pretreated (2 μg/mL, 3h) DUSP2 resWT (Tet) cells showed a DUSP2 dependent dephosphorlyation of ERK1/2 and p38, (K) while STAT3 was not dephosphorylated in a DUSP2 dependent manner in DUSP2 resWT (Tet) cells after doxycycline pretreatment (2 μg/mL, 3 h) and INFα (100 ng/mL) stimulation. For all experiments cells were starved overnight, and majority of experiments were performed in at least three replicates. Expression data are presented as mean ± SEM. Unpaired student’s t test was calculated compared to unstimulated cells, ∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001; CHX = cycloheximide, PMA = phorbol-12-myristate-13-acetate; INFα = interferon alpha, TPM = transcripts per million, ° unspecific band.
Article Snippet: For ERK inhibitor experiments primary CD4 + T or Jurkat wild-type cells were pretreated with or without a final concentration of 1 μM ERK1/2 inhibitor SCH772984 (MedChemExpress) for 30 min before adding the respective stimulation.
Techniques: Western Blot, Activation Assay, Expressing, Quantitative RT-PCR, Control, Phospho-proteomics