Fig. 6: Both Trichuris suis proteins A and B do not exhibit pro-apoptotic activity unlike mammalian BAX or BAK.

The presence of T. suis A and/or B did not a restore the ability of cells deficient for BAX and BAK to undergo apoptosis following etoposide treatment unlike BAK or BAK (data are the mean ± standard deviation of n = 3 biologically independent experiments for all except T. suis A + B where n = 6 combining data from two separate cell lines expressing these proteins; raw data available in Supplementary Data 4) or b enable the release of cytochrome c from the mitochondria (P: mitochondria-containing pellet) into the cytosol (S: soluble fraction) following treatment with BIM BH3 peptide, unlike BAX and BAK. BIM4E is an “inactive” mutant BIM BH3, negative control peptide. Blots were re-probed with anti-BCL-2 (an exclusively membrane-bound protein) antibody as a fractionation control. c Nematode (Plectus sambesii) and non-vertebrate (Helobdella robusta and Hydra vulgaris) BCL-2 proteins that clustered with BAK proteins in the phylogenetic analysis (Fig. 4) were expressed in Bax^−/−/Bak^−/− MEF and localised in both the mitochondria-containing pellet (P) and cytosolic soluble (S) fractions, similar to mammalian BAX. d These BCL-2 orthologues do not have significant pro-apoptotic capacity as demonstrated by their inability to release cytochrome c from the mitochondria (P) fraction into the cytosol (S) fraction following treatment with BIM BH3. Uncropped blots used to construct b–d are provided in Supplementary Fig. 5.