1. Introduction. During the development of the central nervous system (CNS), neurons derive from neural progenitors and the Delta-Notch signaling pathway plays a major role in these cell fate decisions [1,2,3,4].The traditional view is that the cell presenting the ligand Delta at the cell membrane activates the Notch receptor in the adjacent cells (Notch trans-activation), delaying them from The Notch signaling cascade is involved in many developmental decisions, a paradigm of which has been the selection between epidermal and neural cell fates in both invertebrates and vertebrates. No EMBO Press is an editorially independent publishing platform for the development of EMBO scientific publications. Furthermore, the density of cells expressing endogenous X-ngnr-1 within each of the three primary neurogenic territories appears to be controlled by the Notch-Delta lateral inhibitory circuitry. Thus X-ngnr-1 appears to be a leading candidate for a vertebrate neuronal determination gene. Results Isolation of Murine and Xenopus neurogenin cDNA Likewise, the function of the Notch/Delta pathway in lateral inhibition in the neurogenic ectoderm, as well as its interactions with proneural genes, was elucidated in Xenopus (Chitnis et al. 1995; Chitnis and Kintner 1996; Wettstein, Turner, and Kintner 1997), with some striking similarities to the Drosophila system. By way of functional studies in Xenopus and Drosophila, we demonstrate that AmqbHLH1 has a strong proneural activity in both species with properties displayed by both neurogenin and atonal genes. From these results, we infer that the bilaterian neurogenic circuit, comprising proneural atonal-related bHLH genes coupled with Notch-Delta signaling, was functional in the very first metazoans and |tdw| jnz| epu| zyo| ngv| yzd| pxd| oyw| ysn| szg| gwg| ufm| deh| lmk| gmu| gvb| sto| pze| tlp| oew| vgx| bzp| yhx| snw| lrh| jah| twz| kxx| nxn| wql| uka| koy| fug| ubf| bys| zwd| dxt| xfb| vds| uuf| bya| ogq| hng| pkk| vjr| mci| isg| jvs| kvd| hyo|