Journal: Autophagy
Article Title: Deubiquitinase USP15 restricts LC3-dependent targeting of Mycobacterium tuberculosis
doi: 10.1080/15548627.2026.2618632
Figure Lengend Snippet: The catalytic activity of USP15 is necessary for regulating Mtb replication in BV2 cells. ( A ) Schematic of USP15 with the location of the catalytic dead mutation noted in red. Domain abbreviations are as follows: DUSP (domain present in USP) and UBL (ubiquitin-like domain). The catalytic domains (CD) are noted in blue. ( B ) Complementation of BV2 usp15 KO cells with 3XFlag-USP15WT ( usp15 KO::WT) or 3XFlag-Usp15C269A ( usp15 KO::C269A). Western blot demonstrating 3XFlag-USP15 WT or 3XFlag-USP15 C269A in BV2 cell lines. ( C ) CFU of Mtb infection in BV2 WT with empty vector (WT Empty), BV2 usp15 KO with empty vector ( usp15 KO Empty), BV2 usp15 KO complemented with 3XFlag-USP15 WT ( usp15 KO::WT) or BV2 usp15 KO complemented with 3XFlag-USP15 C269A ( usp15 KO:: C269A). CFU values were normalized to Day 0. ( D ) Representative image of mCherry (gray or red) and K63 immunofluorescence (gray or green) with DAPI (blue) in WT Empty, BV2 usp15 KO Empty, BV2 usp15 KO::WT, or BV2 usp15 KO::C269A. Scale bar: 5 μm. ( E ) Quantification of K63 colocalization with mCherry Mtb in WT Empty, BV2 usp15 KO Empty, BV2 usp15 KO::WT, or BV2 usp15 KO::C269A. ( F ) Representative image of mCherry (gray or red) and LC3 immunofluorescence (gray or green) with DAPI (blue) in WT Empty, BV2 usp15 KO Empty, BV2 usp15 KO::WT, or BV2 usp15 KO::C269A. Scale bar: 5 μm. ( G ) Quantification of LC3 colocalization with mCherry Mtb in WT Empty, BV2 usp15 KO Empty, BV2 usp15 KO::WT, or BV2 usp15 KO::C269A. For statistical analysis of CFU, we used two-way ANOVA and Tukey’s multiple comparison test. For statistical analysis of colocalization, we used one-way ANOVA and Tukey’s multiple comparison test. * p<0.05, ** p<0.01, *** p<0.001, **** p<0.0001. Data shown are representative of at least 3 independent experimental replicates.
Article Snippet: The Imaris colocalization function was used to quantify LC3, K63, and K48 colocalization with mCherry Mtb.
Techniques: Activity Assay, Mutagenesis, Ubiquitin Proteomics, Western Blot, Infection, Plasmid Preparation, Immunofluorescence, Comparison