EMBRYONIC EXPRESSION OF THE CHICKEN SOX2, SOX3 AND SOX11 GENES SUGGESTS AN INTERACTIVE ROLE IN NEURONAL DEVELOPMENT

Three chicken Sox (SRY-like box) genes have been identified that show an interactive pattern of expression in the developing embryonic nervo us system. cSox2 and cSox3 code for related proteins and both are pred ominantly expressed in the immature neural epithelium of the entire CN S of HK stage 10 to 34 embryos. cSox11 is related to cSox2 and cSox3 o nly by virtue of containing an SRY-like HMG-box sequence but shows ext ensive homology with Sox-4 at its C-terminus. cSox11 is expressed in t he neural epithelium but is transiently upregulated in maturing neuron s after they leave the neural epithelium. These patterns of expression suggest that Sox genes play a role in neural development and that the developmental programme from immature to mature neurons may involve s witching of Sox gene expression. cSox11 also exhibits a lineage restri cted pattern of expression in the peripheral nervous system.