title: Tracking the origin and divergence of cholinesterases and neuroligins: the evolution of synaptic proteins.
abstract: A cholinesterase activity can be found in all kingdoms of living organism, yet cholinesterases involved in cholinergic transmission appeared only recently in the animal phylum. Among various proteins homologous to cholinesterases, one finds neuroligins. These proteins, with an altered catalytic triad and no known hydrolytic activity, display well-identified cell adhesion properties. The availability of complete genomes of a few metazoans provides opportunities to evaluate when these two protein families emerged during evolution. In bilaterian animals, acetylcholinesterase co-localizes with proteins of cholinergic synapses while neuroligins co-localize and may interact with proteins of excitatory glutamatergic or inhibitory GABAergic/glycinergic synapses. To compare evolution of the cholinesterases and neuroligins with other proteins involved in the architecture and functioning of synapses, we devised a method to search for orthologs of these partners in genomes of model organisms representing distinct stages of metazoan evolution. Our data point to a progressive recruitment of synaptic components during evolution. This finding may shed light on the common or divergent developmental regulation events involved into the setting and maintenance of the cholinergic versus glutamatergic and GABAergic/glycinergic synapses.
authors.affiliation: Dynamique Musculaire et Métabolisme, INRA, Université Montpellier, Place Viala, Montpellier, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Lenfant
authors.forename: Thierry
authors.initials: T
authors.lastname: Hotelier
authors.forename: Yves
authors.initials: Y
authors.lastname: Bourne
authors.forename: Pascale
authors.initials: P
authors.lastname: Marchot
authors.forename: Arnaud
authors.initials: A
authors.lastname: Chatonnet
mesh_terms: D000818:Animals; D015816:Cell Adhesion Molecules, Neuronal / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D002802:Cholinesterases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D019143:Evolution, Molecular; D006801:Humans; D013569:Synapses / Q000378:metabolism*
chemical_list: D015816:Cell Adhesion Molecules, Neuronal; D002802:Cholinesterases