Journal: The Journal of Biological Chemistry

Article Title: CAPN15 is a non-proteasomal, ubiquitin-directed calpain protease that regulates cell adhesion by cleaving E-cadherin

doi: 10.1016/j.jbc.2025.111034

Figure Lengend Snippet: CAPN15 recognizes the ubiquitinated cadherin-catenin complex via the NZF domains. A , differential interference contrast images of HCT116, KO, WTtg, CStg, and NEtg cells. Scale bar, 20 μm. B , the mean log 2 fold change of the protein abundance (CStg versus NEtg immunoprecipitates) with -log 10 p value of the interactome was shown on the x- and y-axes, respectively. Significantly increased proteins were defined as those with the value of the log 2 fold change >1 with p value < 0.05 (plots in a colored area). It should be noted that there was no change in abundance of CAPN15 in the CStg and NEtg immunoprecipitates. C , the heatmap shows the relative abundance of cadherins and catenins in the KO, WTtg, CStg, and NEtg immunoprecipitates. D , KO, WTtg, CStg, and NEtg cells were treated with dimethyl sulfoxide (DMSO; vehicle) or 1 μM MLN7243. Cell lysates were subjected to immunoprecipitation using an anti-FLAG antibody, followed by western blotting. Asterisks indicate nonspecific bands. Vertical lines indicate the ubiquitinated forms. E , immunoprecipitated fraction from DMSO (vehicle)-treated CStg cells was incubated with or without ubiquitin-specific protease 2 (USP2cc), followed by western blotting. The asterisk indicates the non-specific band. Vertical lines indicate the ubiquitinated forms.

Article Snippet: Anti-FLAG immunoprecipitate prepared from CStg cells was incubated with 1 μM USP2 catalytic domain (USP2cc; R&D Systems) for 1 h at 37 °C.

Techniques: Quantitative Proteomics, Immunoprecipitation, Western Blot, Incubation, Ubiquitin Proteomics