Retinoic acid-binding protein, rhombomeres and the neural crest.

摘要: We have investigated by immunocytochemistry the spatial and temporal distribution of cellular retinoic acid-binding protein (CRABP) in developing nervous system chick embryo order to answer two specific questions: do neural crest cells contain CRABP where when CRABP-positive neuroblasts first arise tube? With regard crest, we compared staining with HNK-1 (a marker migrating crest) found that they indeed co-localise, but cephalic trunk behave slightly differently. In region tissues such as frontonasal mass branchial arches, immunoreactivity is intense at early stages, it disappears appears. Thus patterns not overlap, are complementary. trunk, stain same cell populations time, those through anterior halves somites. tube, appear rhombencephalon just after folds close then a particular pattern appears within rhombomeres hindbrain. Labelled present future spinal cord, posterior up rhombomere 6 4 thus producing single stripe pattern. This dynamic gradually changes begin label. The similarity this initial arrangement certain homeobox genes mouse stimulated us examine expression chicken Hox-2.9 gene. show stage 15 gene closely related CRABP. relationship between acid, discussed.