Fig 1. Nucleotide and amino acid sequence alignments of EDMTFH versus histidine-rich protein (HRP).

(A) The nucleotide sequences of the coding region of chicken EDMTFH [13] and of the chicken HRP cDNA reported previously [29] were aligned. Translations into amino acid sequences are shown above and below the sequences, respectively. Note that insertions and deletions (red shading) in the cDNA sequence relative to the chicken EDMTFH gene in the current genome assembly cause reading frameshifts leading to the prediction of a different carboxy-terminus of HRP (blue fonts) relative to EDMTFH. Sequences corresponding to peptides that were previously identified in feather extracts are marked underlined feather proteins peptides (underlined) corresponding to EDMTFH were identified by (blue underline [29], green underlines [13]). Histidine (H) residues are highlighted by green shading. The stop codon of EDMTFH is marked with an asterisk. (B) Alignment of amino-terminal amino acid sequences of EDMTFH [13] and HRP, as determined by direct sequencing of proteins isolated from feathers [29, 38]. Predicted HRP-B residues that deviate from the EDMTFH sequence at positions of histidines (H) are shaded grey.