title: Some polypeptides in the nervous system of the marine worm, Nereis diversicolor, are related to the sodium influx stimulating peptide of the pulmonate freshwater snail, Lymnaea stagnalis.
abstract: Total mRNA, extracted from brain of the marine worm, Nereis diversicolor (Annelida, Polychaeta), was translated either in vitro using a rabbit reticulocyte lysate or in ovo (Xenopus laevis oocyte). The synthesized polypeptides were analyzed by electrophoresis and Western blotting techniques using polyclonal antisera raised against three peptides: sodium influx stimulating peptide (SISP) sequences 10-19 and 67-76 and a monoclonal antibody raised against purified native SISP (1-77) of Lymnaea stagnalis. Among the products translated in vitro, three polypeptides of 80, 72, and 64 kDa were recognized by the anti-SISP (10-19) polyclonal antiserum and by the monoclonal antiserum, but not by anti-SISP (67-76). Some of the in ovo translated products showed almost identical immunoreactivity to both the anti-SISP (10-19) and the monoclonal antibody. These polypeptides have molecular masses of 80, 72, and 43 kDa. No polypeptides were recognized by anti-SISP (67-76). Western blotting analysis of brain extracts revealed a number of proteins that reacted with the antiserum raised against SISP (10-19) and the monoclonal antiserum. Several perikarya of brain ganglionic nuclei and ventral nerve cord were immunoreactive to anti-SISP (10-19). The monoclonal antiserum gave similar results, although with a less intense immunoreaction. The infracerebral region was also stained, suggesting that the immunoreactive material is released as a true neurohormone into the hemolymph. The largest polypeptides, in particular those translated from brain mRNA, could be neuropeptide precursors containing a SISP-related sequence.
authors.affiliation: Endocrinologie des Invertébrés, CNRS URA 148, Université de Lille, Villeneuve d'Ascq, France.
authors.forename: T
authors.initials: T
authors.lastname: Dugimont
authors.forename: N
authors.initials: N
authors.lastname: Dhainaut-Courtois
authors.forename: J
authors.initials: J
authors.lastname: Van Minnen
authors.forename: N D
authors.initials: ND
authors.lastname: de With
authors.forename: J J
authors.initials: JJ
authors.lastname: Curgy
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism; D001923:Brain Chemistry; D002474:Cell-Free System; D007150:Immunohistochemistry; D008195:Lymnaea / Q000737:chemistry; D009420:Nervous System / Q000737:chemistry; D009479:Neuropeptides / Q000032:analysis*; D011077:Polychaeta / Q000737:chemistry*; D012964:Sodium / Q000378:metabolism
chemical_list: D000911:Antibodies, Monoclonal; D009479:Neuropeptides; D012964:Sodium