Fig. 2. Hro-hh is an hh homolog. (A) Domain alignment of HH-homologs in leech (Hro-hh; accession number AF517943), mouse (Mus-shh, Q62226; Mus-ihh, P97812; Mus-dhh, Q61488), human (Hom-shh, Q15465), zebrafish (Dan-shh, A49426), Amphioxus (Amp-hh, CAA74169) and fruitfly (Dro-hh, L02793): secreted HH amino terminus (HH-N, gray box); within the less well conserved carboxy-terminal fragments (HH-C), putative autoprocessing sequence motifs (PASM, black box) and the cell division sequence motif (CDSM, hatched box) in Hro-hh are indicated. (B) Alignment of HH-Ns, including the available sequence from a mollusc, Patella vulgata (Pat-hh, AF435840). (C) Alignment of PASMs in HH-Cs. Gray shading in B and C indicates conserved residues. shh, sonic hedgehog; ihh, Indian hedgehog; dhh, desert hedgehog.