Our interpretation then is that the referees are concerned the mutant SNX5 (F136A) may also impact the folding and normal heterodimerisation of the SNX5 protein with either SNX1 or SNX2 Note that SNX5 does not homodimerise with itself, nor heterodimerise with SNX6 and SNX32 is not expressed endogenously in HeLa cells. We believe this concern is addressed by the fact that the SNX5 (F136A) mutant is recruited normally to endosomes (Figure 4C). As this will only occur in a heterodimeric complex with either SNX1 or SNX2 we therefore conclude that the mutant is properly folded and otherwise functional.