KRAJNIAK, Kevin G.; Southern Illinois Univ. Edwardsville: A survey of invertebrate FMRFamide-Related Peptides: Annelid Endocrine Disruptors.
The FMRFamide-related peptides (FaRPs) are a group of neuropeptides that share a similar amino acid sequence. The first member of this family was the tetrapeptide FMRFamide, which was isolated from the ganglia of the clam, Macrocallista nimbosa, by Price and Greenberg in 1977. Its name was derived from the single letter abbreviations for the amino acids in the sequence and the fact that it was amidated at the C-terminus. Since then researchers have used antibodies to FMRFamide to identify a large number of FaRPs from many of the invertebrate phyla. More peptides have been predicted by screening cDNA libraries with sequences based on amino acid composition of FMRFamide. FaRPs have a variety of functions in invertebrates and can act as either neurotransmitters, neuromodulators, or neurohormones. Each function is both species and tissue specific. Studies of the FaRP receptor show that most are linked to a second messenger system, however at least one receptor is a chemically gated sodium channel. On going studies are examining these peptides from the molecular level to the level of the whole animal. Like the study of neuropeptides there is now a growing body of literature elucidating the actions of endocrine disruptors in invertebrates. In annelids it has been shown that endocrine disruptors can accumulate in both polychaete and oligochaete worms. These pollutants had many effects on these annelids. For example tri-�butyltin, the active ingredient in marine antifouling paints, was genotoxic, cytotoxic, and had developmental effects on the polychaete Platynereis dumerilii, while the polychlorinated biphenyl, Aroclor, suppressed phagocytosis in the coelomocytes of two different species of earthworms. The development of annelid assays like the earthworm coelomocyte assay will allow for screening of many more suspected endocrine disruptors and shed light on their biological activity.
