Figure 1
From: Expression and processing of mature human frataxin after gene therapy in mice
Alignment of mature hFXN (Uniprot Q16595) and mFXN (Uniprot Q35943). Amino acids in green are specific to hFXN while those in purple are specific to mFXN. Translocation of full-length FXN to the mitochondria followed by two sequential cleavages by MPP results in the formation of mature hFXN and mFXN as 130 amino acid proteins. Quantification of mature hFXN is based on the S81GTLGHPGSLDETTYER97 tryptic peptide (N), while quantification of mature mFXN is based on the L78GTLDNPSSLDETAYER94 tryptic peptide (N). Extra-mitochondrial mature mFXN is formed through an unknown mechanism and is detected as the truncated N-1 tryptic peptide G79TLDNPSSLDETAYER94. Other proteoforms are detected by further truncations on the N-terminal tryptic peptide as N-2, N-3, N-4, N-5, and N-6. hFXN = human frataxin; mFXN = mouse frataxin; MPP = mitochondrial processing peptidase.
