Journal: Cell reports
Article Title: Restraint of inflammasome-driven cytokine responses through the mRNA stability protein TTP
doi: 10.1016/j.celrep.2025.115340
Figure Lengend Snippet: (A) WT and GSDMD knockout (GSDMD −/− ) iBMDMs were primed with LPS and stimulated with 10 μM nigericin over a time course of 45 min. Cellular lysates were examined by western blot for changes in electrophoretic mobility of TTP. (B) TTP knockout iBMDMs were generated on a WT and GSDMD −/− background using CRISPR-Cas9 technology. Individual clones were assessed for knockout via sequencing and western blot. Knockout clones were then pooled and assessed via western blot (top). TTP −/− cells were then reconstituted with empty vector (EV), WT TTP, TTP S220A, or TTP 5S to A (bottom). (C) TTP −/− iBMDMs were reconstituted with empty vector or myc-TTP. After a 45-min nigericin time course, myc-TTP was immunoprecipitated from whole cell lysate and assayed via western blot for phosphorylation of the ERK substrate motif PXSP. (D) A schematic of TTP outlining its functional domains and highlighting its two PXSP sites. Sequences surrounding the PXSP sites are given for mouse, human, and rat TTP, as well as drosophila Tis11 (a TTP analog). All numbering refers to the mouse protein. NES, nuclear export signal. (E) HEK293T cells were transiently transfected with ERK1, constitutively active MEK1, and WT or phosphosite mutant TTP. TTP was immunoprecipitated from whole cell lysate and the pulldown was assayed for phospho-PXSP motifs via western blot. (F) TTP −/− iBMDMs were reconstituted with WT and S220A myc-TTP. After a 45-min nigericin time course, myc-TTP was immunoprecipitated from whole cell lysate and assayed via western blot for phosphorylation of the ERK substrate motif PXSP. Western blots are representative of at least three independent experiments.
Article Snippet: Antibodies used were phospho-ERK1/2 (Cell Signaling #9106), ERK1/2 (Cell Signaling #4695), TTP (Cell Signaling #71632), phospho-MEK1/2 (Cell Signaling #9154), MEK1/2 (Cell Signaling #8727), myc-tag (Cell Signaling #2278), phospho-PXSP (Cell Signaling #2325), GSDMD (Abcam #ab209845), HRP-linked anti-rabbit IgG (Cell Signaling #7074), and HRP-linked anti-mouse IgG (Cell Signaling #7076).
Techniques: Knock-Out, Western Blot, Generated, CRISPR, Clone Assay, Sequencing, Plasmid Preparation, Immunoprecipitation, Phospho-proteomics, Functional Assay, Transfection, Mutagenesis