J Comp Neurol 2006 May 10;4962:244-51. doi: 10.1002/cne.20939.

Neuron-specific expression of a synaptotagmin gene in the sea urchin Strongylocentrotus purpuratus.

???displayArticle.abstract???
Interest in chordate evolution has emphasized a need for a better understanding of the comparative neuroanatomy of invertebrate deuterostomes. However, molecular and genetic approaches to neurobiological studies in these groups are hampered by a lack of neuron-specific molecular markers. A monoclonal antibody, 1E11, is neuron specific and is useful in identification of neural structures in larvae and adults of echinoderms, hemichordates, and urochordates. To identify a neuron-specific gene product, we have characterized the antigen recognized by 1E11. In immunoblots and immunoprecipitations of neural tissue from adult Strongylocentrotus purpuratus, 1E11 recognizes a 57-kDa band. Tandem mass spectrometry of trypsin digests of the 57-kDa band permitted peptide mass mapping and sequencing of five peptides. All of the sequenced peptides, and 12 additional mass-mapped peptides, are found within the open reading frame of a cDNA encoding synaptotagmin B (Sp-SynB). In situ RNA hybridizations with synaptotagmin B probes with S. purpuratus larvae reveal a pattern of expression that is similar to that revealed by the antibody 1E11. Antibodies produced against a bacterially expressed Sp-SynB protein recognize a 57-kDa protein and colocalize with 1E11. When a full-length Sp-SynB cDNA is expressed in chicken embryonic cells, the cells become immunoreactive to 1E11. We conclude that synaptotagmin B is a gene expressed in neurons that has conserved epitopes in other invertebrate deuterostomes.

???displayArticle.pubmedLink??? 16538680
???displayArticle.link??? J Comp Neurol


Genes referenced: LOC100887844 LOC115917880
???displayArticle.antibodies??? LOC115917880 Ab1 LOC115917880 Ab2