Fig. 1

Summary of the main features of GPI-AP and FT-GPI TM. The N-terminal ER-targeting signal and C-terminal GPI-anchoring signal are generally associated with the ER-membrane via a hydrophobic helix. A mature GPI-AP peptide is produced after cleavage of the signal peptide and at site of the GPI-anchoring signals. FT-GPI software uses the TMPred score and distance to the protein extremity as identifying markers of hydrophobic regions at both extremities of the propeptide. The parameters S_start, S_end and S_internal correspond to TMPred scores of the N-terminal, C-terminal and all internal hydrophic helices, respectively. They are controlled with -n, -c and -i options of the software. FT-GPI expects to encounter the first amino acid of the N-terminal region between the first residue and position d_start of the protein. FT-GPI expects to encounter the last amino acid of the C-terminal region after the d_end position on the protein