atoh8 expression pattern in early zebrafish embryonic development

AbstractAtonal homologue 8 (atoh8) is a basic helix-loop-helix transcription factor expressed in a variety of embryonic tissues. While several studies have implicatedatoh8 in various developmental pathways in other species, its role in zebrafish development remains uncertain. So far, no studies have dealt with an in-depth in situ analysis of the tissue distribution ofatoh8 in embryonic zebrafish. We set out to pinpoint the exact location ofatoh8 expression in a detailed spatio-temporal analysis in zebrafish during the first 24  h of development (hpf). To our surprise, we observed transcription from pre-segmentation stages in the paraxial mesoderm and during the segmentation stages in the somitic sclerotome and not—as previously reported—in the myotome. With progressing maturation of the somites, the restriction ofatoh8 to the sclerotomal compartment became evident. Double in situ hybridisation withatoh8 andmyoD revealed that both genes are expressed in the somites at coinciding developmental stages; however, their domains do not spatially overlap. A second domain ofatoh8 expression emerged in the embryonic brain in the developing cerebellum and hindbrain. Here, we observed a specific expression pattern which was again in contrast to the previously published suggestion ofatoh8 transcription in neural crest cells. Our findings point towards a possible role ofatoh8 in sclerotome, cerebellum and hindbrain development. More importantly, the results of this expression analysis...
Source: Histochemistry and Cell Biology - Category: Biomedical Science Source Type: research