Cloning and expression of noz1, a zebrafish zinc finger gene related to Drosophila nocA

We report the isolation of noz1, a novel zebrafish zinc finger gene which d isplays sequence similarity to Drosophila nocA. noz1 transcripts are detect ed at the shield stage within the germ ring and excluded from the most dors al region. By the end of gastrulation, noz1 is expressed in the presumptive hindbrain and spinal cord as well as in the forming tailbud. During somito genesis noz1 shows a dynamic expression in the midbrain-hindbrain boundary, hindbrain and spinal cord. This results, at 23 hpf, in a graded expression with the highest level in rhombomeres 2 and 3, and the lowest in the spina l cord. Expression analysis in swirl and chordino mutants as well as in ret inoic acid treated embryos indicate that noz1 is activated by BMP antagonis ts and neural posteriorizing signals. (C) 2001 Elsevier Science Ireland Ltd . All rights reserved.