OVEREXPRESSION OF NEUROGENIN INDUCES ECTOPIC EXPRESSION OF HUC IN ZEBRAFISH

Several basic helix-loop-helix (bHLH) transcription factors are known to be involved in vertebrate neurogenesis. To investigate their roles in zebrafish neurogenesis, we isolated cDNAs for homologues of neuroge nin and Math-1/atonal. The transcription of neurogenin was first detec table in zebrafish nervous system at late gastrulation stage. The expr ession of zebrafish neurogenin precedes and overlaps that of HuC, one of the earliest neuronal precursor markers. Injection of neurogenin mR NA into early stage zebrafish embryos induced ectopic expression of Hu C. These results suggest that neurogenin may participate in the genera tion of HuC-expressing cells, implying its role in neuronal determinat ion in zebrafish. (C) 1997 Elsevier Science Ireland Ltd.