Table 1: Predicted FMRFamide-like precursors and their mature peptides in C. elegans. The FLP-encoding genes flp-29, flp-30 and flp-31 have been identified as parasite-specific, and therefore do not occur in C. elegans [1]. However, these genes were eventually characterized as orthologs of C. elegans flp-28, flp-2 and flp-15 respectively [2]. Peptide sequences are shown without any posttranslational modifications. Sequences indicated in bold have been biochemically isolated in previous studies. Possible modifications include: N-terminal cyclization of a glutamic acid or glutamine residue and pyroglutamate formation, C-terminal conversion of a glycine residue into an amide, formation of disulfide bridge between two cysteine residues.

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