title: Novel, posterior sensory organ in the trochophore larva of Phyllodoce maculata (Polychaeta).
abstract: A new posterior sensory organ (PSO), located at the dorsal midline of the hyposphere, is described by immunocytochemical detection of acetylated alpha tubulin and serotonin (5-HT) in a laser-scanning microscope, as well as three-dimensional reconstructions after optical serial sectioning in the trochophore larva of the polychaete Phyllodoce maculata (Phyllodocidae). The unpaired PSO consists of five bipolar sensory cells, two of them being 5-HT immunopositive, which send axons to the cerebral ganglion and prototroch nerve. The dendrites of these cells project to the surface and bear one cilium each. A single neuronal fibre from the apical sensory organ innervates the PSO.
authors.affiliation: Institute of Developmental Biology, Russian Academy of Sciences, Moscow 117808, Russia. lnezlin@gwdg.de
authors.forename: L P
authors.initials: LP
authors.lastname: Nezlin
authors.forename: E E
authors.initials: EE
authors.lastname: Voronezhskaya
mesh_terms: D000818:Animals; D007150:Immunohistochemistry; D007814:Larva / Q000033:anatomy & histology / Q000737:chemistry; D018613:Microscopy, Confocal; D011077:Polychaeta / Q000033:anatomy & histology* / Q000737:chemistry; D012426:Russia; D012623:Seawater; D011984:Sensory Receptor Cells / Q000033:anatomy & histology*; D012701:Serotonin / Q000032:analysis; D014404:Tubulin / Q000032:analysis
chemical_list: D014404:Tubulin; D012701:Serotonin