TRPM8 channels require PtdIns(4,5)P2 for activity. In order to ensure that expression of scPPX1 did not affect PtdIns(4,5)P2 levels in the cells, we have monitored the distribution of the GFP-tagged PH-domain of phospholipase C δ1 in control HEK cells, and in cells transfected with scPPX1. Co-expression of scPPX1 did not change the plasma membrane localization of the GFP tagged PH domain, indicating that plasma membrane PtdIns(4,5)P2 levels were not significantly altered (data not shown).