DBHR, a gene with homology to dopamine beta-hydroxylase, is expressed in the neural crest throughout early development.
In a screen for genes involved in neural crest development, we identified DBHR (DBH-Related), a putative monooxygenase with low homology to dopamine beta-hydroxylase (DBH). Here, we describe novel expression patterns for DBHR in the developing embryo and particularly the neural crest. DBHR is an early marker for prospective neural crest, with earliest expression at the neural plate border where neural crest is induced. Furthermore, DBHR expression persists in migrating neural crest and in many, though not all, crest derivatives. DBHR is also expressed in the myotome, from the earliest stages of its formation, and in distinct regions of the neural tube, including even-numbered rhombomeres of the hindbrain. In order to investigate the signals that regulate its segmented pattern in the hindbrain, we microsurgically rotated the rostrocaudal positions of rhombomeres 3/4. Despite their ectopic position, both rhombomeres continued to express DBHR at the level appropriate for their original location, indicating that DBHR is regulated autonomously within rhombomeres. We conclude that DBHR is a divergent member of a growing family of DBH-related genes; thus, DBHR represents a completely new type of neural crest marker, expressed throughout the development of the neural crest, with possible functions in cell-cell signaling.
Knecht
A K
AK
Division of Biology, California Institute of Technology, 139-74, Pasadena, California 91125, USA.
Bronner-Fraser
M
M
D000595:Amino Acid Sequence; D000818:Animals; D000943:Antigens, Differentiation; D030161:Avian Proteins; D002465:Cell Movement; D002642:Chick Embryo; D002874:Chromosome Mapping; D004299:Dopamine beta-Hydroxylase; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000196:embryology; D009419:Nerve Tissue Proteins; D009432:Neural Crest / Q000196:embryology* / Q000601:surgery; D010105:Oxygenases / Q000235:genetics / Q000302:isolation & purification*; D012249:Rhombencephalon / Q000196:embryology; D017386:Sequence Homology, Amino Acid; D019170:Somites; D014018:Tissue Distribution
D000943:Antigens, Differentiation; D030161:Avian Proteins; D009419:Nerve Tissue Proteins; C431068:DBHR protein, chicken; D010105:Oxygenases; D004299:Dopamine beta-Hydroxylase