GFG contains a predicted mitochondrial targeting signal peptide sequence. (A) Mitochondrial targeting signal peptides were predicted in the N-terminal sequence of GFG from a several species using MitoProt II.0a The predicted signal peptide cleavage site is indicated by the open triangle. In rat and mouse, but not other species, a potential monobasic prohormone cleavage site was also identified (solid triangles). Note: raGFG: the N-terminal sequence is identical in raGFG, rGFGΔ2 and rGFGΔ2/3. raGFGc, an N-terminally truncated isoform predicted from the Celera rat genome assembly database, is >80 identical to human GFGb. (B) Edmunson helical wheel illustration of the human and rat MTS sequences. Hydrophobic and uncharged amino acids are depicted in white, positively charged residues in black, and negatively charged with gray circles.