Asakawa, K., Higashijima, S.I., and Kawakami, K. (2012) An mnr2b/hlxb9lb enhancer trap line that labels spinal and abducens motor neurons in zebrafish. Developmental dynamics : an official publication of the American Association of Anatomists. 241(2):327-332.
Animal models that allow the visualization of specific classes of neurons are crucial for the study of the function of neuronal networks. We performed an enhancer trap screening in zebrafish and generated a collection of transgenic lines that expressed green fluorescent protein (GFP) in a spatially and temporally restricted manner. Among the fish generated, we found an insertion of the enhancer trap construct in the vicinity of the mnr2b/hlxb9lb gene encoding the mnx class of homeodomain transcription factor, which gave rise to GFP expression predominantly in spinal motor neurons and abducens motor neurons. During embryogenesis, GFP expression was also detected in endodermal and mesodermal tissues, where mnr2b is known to be expressed. These results indicate that the enhancer trap construct recapitulated the expression pattern of the mnr2b gene and this transgenic line should be useful for the visualization of the spinal and abducens motor neurons in the developing nervous system.