Fig. 3

The CD domain of ERK1/2 mediates LRRC4-ERK1/2 binding and its cytoplasm localization. a Schematic of the ERK1 (ERK2) full-length protein, the ERK1 (ERK2)-ΔCD mutant protein, and the GST-ERK1 (ERK2)-D fusion protein. b Confocal fluorescence microscopy of HEK293 cells co-transfected with different plasmids to assess the effect of ERK1/2 CD domain deletion on the localization of LRRC4 and ERK1/2. The merged image shows that ERK1 or ERK2 underwent nuclear translocation after the CD domain of ERK1 or ERK2 was deleted. The signals were measured by ImageJ software. Scale bars, 50 μm. c GST pull-down assays showed that the CD domain of ERK1/2 pulled down LRRC4. Western blot and Coomassie blue staining analysis of whole-cell lysate (WCL) showed the expression of the GST fusion protein. (− : IPTG negative; + : IPTG positive)