A single origin of the central nervous system?
As Denes et al. (2007) reveal in this issue, the expression profile and roles of genes that pattern the nervous system in embryos of chordates and annelids are surprisingly similar. This extraordinary conservation suggests that the patterning mechanism has been inherited largely unchanged from the bilaterian common ancestor and that the central nervous system, although dorsal in fish and ventral in worms, is an ancient characteristic of animals.
Telford
Maximilian J
MJ
Department of Biology, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK. m.telford@ucl.ac.uk
D000818:Animals; D005075:Biological Evolution; D019521:Body Patterning; D002490:Central Nervous System / Q000196:embryology*; D043344:Chordata / Q000196:embryology* / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D011077:Polychaeta / Q000196:embryology* / Q000235:genetics