Figure 3
From: Expression and processing of mature human frataxin after gene therapy in mice
Detection and quantification of mature mFXN and its N-terminal tryptic peptides in the mouse heart following hFXN gene therapy. (a) Representative chromatograms from 2D-nano-UHPLC-PRM/HRMS analysis of mature mFXN N-terminal tryptic peptides in the heart of a mouse administered a high dose (1.8e13 gc/kg) of AAVrh.10hFXN. y-ion indicates the number of amino acids from the carboxy terminus that are present in this ion. Peptide retention times and relative amounts are shown on the left of the relevant signal. (b) Absolute concentrations of Mt and Extra-mt mature mFXN proteoforms in mouse heart after administration of one of three different doses of AAVrh.10hFXN (low dose = 1.8e12 gc/kg, n = 6; mid dose = 5.7e12 gc/kg, n = 4; high dose = 1.8e13 gc/kg, n = 8) or vehicle (n = 5). While there were six mice treated with mid-dose AAVrh.10hFXN, insufficient heart sample precluded analysis of two mice. (c) Relative amounts of mature mFXN proteoforms in mice after administration of the same doses of AAVrh.10hFXN or vehicle (sample sizes as above). (b, c) Data are expressed as mean ± s.e.m. 2D-nano-UHPLC-PRM/HRMS = two-dimensional nano-ultra-high performance liquid chromatography-parallel reaction monitoring high-resolution mass spectrometry; AAVrh.10hFXN = adeno-associated virus rhesus serotype 10 encoding human frataxin; Extra-mt = extra-mitochondrial; hFXN = human frataxin; mFXN = mouse frataxin; Mt = mitochondrial; m/z = mass-to-charge ratio; NL = normalized signal level; s.e.m. = standard error of the mean.
