Fig. 1.

Nucleotide and deduced amino acid sequences of Homarus americanus prepro-myosuppressin. (A) Nucleotide sequence of Homarus americanus prepro-myosuppressin (accession no. GQ303179). The open reading frame of the cDNA, including the stop codon, is shown in bold font, with the 3′ polyadenylation signal sequences indicated by underline in black. (B) Deduced amino acid sequence of Homarus americanus prepro-myosuppressin. The signal peptide is shown in grey, with prohormone convertase cleavage loci shown in black. The encoded myosuppressin isoform is shown in red, with additional precursor-related peptides in blue. The asterisk indicates the position of the stop codon. (C) Putative processing scheme resulting in the production of myosuppressin from its precursor protein. The first line of sequence shows the full-length prepro-hormone with the locus of cleavage locus for signal peptidase underlined. The second line of sequence shows the cleaved pro-hormone with the loci for prohormone convertase underlined. The third line of sequence shows the immature myosuppressin peptide with the site of action for carboxypeptidase underlined. The fourth line of sequence shows the peptide resulting from carboxypeptidase activity with the Gly destined for a-amidation underlined. The fifth line of sequence shows the amidated peptide with the Gln destined for cyclization underlined. The final line of sequence shows the putative, mature myosuppressin after full post-translational processing.