Methods Drosophila stocks and maintenance The Drosophila melanogaster Canton S infected with the Wolbachia strain wMel (IC&G, Russia) and D. melanogaster w1118 infected with wMelPop (a kind gift from prof. S. O’Neill, The University of Queensland, Australia) were used in these experiments. Flies were maintained at 25 °C either on a standard yeast-agar medium or on daily replaced rich food

(standard medium covered with wet yeast paste). To obtain uninfected D. melanogaster w1118T , flies were raised on food supplemented with buy Avapritinib tetracycline at 0.03% for two generations, then on standard food for more than three generations [43]. Confirmation of the infection status of each stock was provided by PCR. For this purpose, total DNA extracted from fly ovaries and wsp 81F/wsp 691R primers for amplifying a Wolbachia surface protein gene fragment were used [45]. Acridine

orande staining Acridine orange (AO), a vital stain highly specific to apoptotic nuclei, was used [46]. Ovaries were dissected from 5-day old flies in EBR buffer (130 mM NaCl, 4.7 mM KCl, 1.9 mM CaCl2, 10 мM Hepes pH 6.9), stained with AO (Merck), 5 μg/ml, in 0.1 M sodium phosphate buffer, pH 7.2, for 3 min at room temperature [12, 47]. Samples were placed onto glass slides and covered with halocarbon oil (KMZ Chemicals Ltd.). They were viewed under an Axioscop 2 plus fluorescence microscope (Zeiss) using an appropriate filter (Zeiss filter AZD5582 set 02). Time elapsed from dissection to the end of viewing was restricted, 20 min. Staining of nuclei varied from bright yellow to brilliant orange, depending on the stage of degeneration [46]. The percentage of AO-staining germaria was expressed as the ratio of the number of

AO-stained germaria containing apoptotic cells to the total number of analysed germaria. Three experiments were performed for each of the 4 D. melanogaster groups (w1118, w1118T stocks, standard food; w1118, w1118T, rich food). In each replicate, Glycogen branching enzyme ovaries were dissected from 6 flies, 7-12 germaria per fly were analysed. In all, about 1350 AO-stained germaria were analysed. Bartlett’s test was used to check homogeneity of variances. Two-way ANOVA was used to determine the significance of the difference between the frequency of apoptosis of the uninfected and Wolbachia-infected flies maintained on different food. TUNEL assay TUNEL was the independent assay of detection of apoptotic cells. TUNEL is advantageous because preferentially labeling apoptotic cells relatively late in the apoptotic process [48]. Ovaries were dissected from 5-day old flies in phosphate-buffered saline (PBS), fixed in PBS containing 4% formaldehyde plus 0.1% Triton X-100 for 25 min. Then, they were separated into individual ovarioles, 4EGI-1 solubility dmso rinsed briefly in PBS twice and washed in PBS three times for 5 min each. Ovarioles were made permeable with 20 μg/ml proteinase K in PBS for 20 min at room temperature, this was followed by 3 washes in PBS for 5 min each.