ワタナベ　ケイスケ   渡辺　啓介    所属   新潟薬科大学  医療技術学部 臨床検査学科    職種   教授
言語種別	英語
発行・発表の年月	2006/04
形態種別	論文
査読	査読あり
標題	Dorsally derived netrin 1 provides an inhibitory cue and elaborates the 'waiting period' for primary sensory axons in the developing spinal cord
執筆形態	共著
掲載誌名	DEVELOPMENT
掲載区分	国外
出版社・発行元	COMPANY OF BIOLOGISTS LTD
巻・号・頁	133(7),pp.1379-1387
著者・共著者	K Watanabe,N Tamamaki,T Furuta,SL Ackerman,K Ikenaka,K Ono
概要	Dorsal root ganglion (DRG) neurons extend axons to specific targets in the gray matter of the spinal cord. During development, DRG axons grow into the dorsolateral margin of the spinal cord and projection into the dorsal mantle layer occurs after a 'waiting period' of a few days. Netrin 1 is a long-range diffusible factor expressed in the ventral midline of the developing neural tube, and has chemoattractive and chemorepulsive effects on growing axons. Netrin 1 is also expressed in the dorsal spinal cord. However, the roles of dorsally derived netrin 1 remain totally unknown. Here, we show that dorsal netrin 1 controls the correct guidance of primary sensory axons. During the waiting period, netrin 1 is transiently expressed or upregulated in the dorsal spinal cord, and the absence of netrin 1 results in the aberrant projection of sensory axons, including both cutaneous and proprioceptive afferents, into the dorsal mantle layer. Netrin 1 derived from the dorsal spinal cord, but not the floor plate, is involved in the correct projection of DRG axons. Furthermore, netrin 1 suppresses axon outgrowth from DRG in vitro. Unc5c(rcm) mutant shows abnormal invasion of DRG axons as observed in netrin 1 mutants. These results are the first direct evidence that netrin 1 in the dorsal spinal cord acts as an inhibitory cue for primary sensory axons and is a crucial signal for the formation of sensory afferent neural networks.
DOI	10.1242/dev.02312
ISSN	0950-1991
NAID	10028202461
PMID	16510500