a, b, Representative images (a) and quantification (b) of GFP–LC3 puncta in vastus lateralis muscles of wild-type GFP-LC3 and Tlr9−/−;GFP-LC3 mice at rest or after exercise, with and without chloroquine pretreatment. Scale bars, 20 μm. Arrows mark representative puncta, counted in b. More than 15 randomly chosen fields were used per mouse and an average value was determined for each mouse. Images are from one representative experiment, and quantitative data are the combined results of two independent experiments. Similar results were observed in each experiment. Data points are individual mice (sample size in parentheses). c, d, Representative western blots (c) and quantification (d) of beclin 1 co-immunoprecipitated with TLR9–HA at serial time points after exercise in vastus lateralis muscles of TLR9–HA mice crossed to either BCL2 AAA mice or wild-type littermates. Western blots are from one representative experiment, and quantification data are the combined results from three independent experiments. Similar results were observed in each experiment. Data points are individual mice (sample size in parentheses). e, Co-immunoprecipitation of transiently expressed Flag–beclin 1 with Myc–BCL2 in HeLa cells stably expressing wild-type Myc–BCL2 or BCL2 AAA19 grown in normal medium or subjected to 2-h glucose starvation. Similar results were observed in three independent experiments. f, g, Representative western blots (f) and quantification (g) of Flag–beclin 1 co-immunoprecipitated with TLR9–HA in HeLa cells stably expressing wild-type Myc–BCL2 or BCL2 AAA grown in normal medium or subjected to 2-h glucose starvation. Data are mean ± s.e.m. from three experiments; sample size is indicated in parentheses. In b, an unpaired two-tailed t-test was used to compare different conditions for each genotype. A two-way ANOVA was used to compare the magnitude of changes between different conditions in mice of different genotypes. In d, a one-way ANOVA was used to compare 0-min and 20-min exercise conditions for each genotype. A two-way ANOVA was used to compare the magnitude of changes between 0- min and 20-min exercise conditions in mice of different genotypes. In g, an unpaired two-tailed t-test was used. For uncropped gels, see Supplementary Fig. 1. Source data