Figure 4.

Selective autophagy of LGP⁺ membranous aggregates differs from Salmonella xenophagy. (A to C) Confocal microscopy images showing that ubiquitin (A, B) and CALCOCO2 (C) decorate damaged Salmonella-containing vacuoles (SCV) at 2 hpi but are not detected at 8 hpi in the LGP⁺ membranous aggregates. Panel B, in which the fluorescence signal was processed to appear with higher intensity, shows ubiquitinated components in the entire cell. Arrows indicate intracellular bacteria. Ubiquitin was detected in NRK49F rat fibroblasts whereas CALCOCO2 was detected in BJ-5ta human fibroblasts. Bacteria (dsRed); Ubiquitin (UBIQ). Scale bars: 5 μm (A, (C)panels), 10 μm (B panel). (D) Percentage of ubiquitin- and CALCOCO2-positive SCV in fibroblasts and epithelial cells quantified at 2 hpi by epifluorescence microscopy. Data are the means and standard deviations from 3 independent experiments. n.s., not significant (Student t test).