1. Roles of Neuregulin, an ErbB ligand, in the maintenance of muscles
- Author
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Sehara-Fujisawa, Atsuko, Sato, Fuminori, Sato, Tomomi, and Iida, Atsuo
- Abstract
第25回宇宙利用シンポジウム(2009年1月14日-15日, 宇宙航空研究開発機構宇宙科学研究本部相模原キャンパス), The Twenty-fifth Space Utilization Symposium (January 14-15, 2009: ISAS/JAXA Sagamihara, Japan), Maintenance of skeletal muscle requires responses to mechanicals stresses caused by stretch of muscles, which was demonstrated by effects of exercise and gravity. The stress responses include factors intrinsic to muscle and extrinsic ones. The formers include IGF-1, and the latters include membrane-anchored Neuregulin/ARIA (acetylcholine receptor inducing activity) generated in neuronal cells. Some of ADAM (A Disintegrin And Metalloprotease) family proteases modulate the ectodomain shedding of various membrane proteins, such as membrane-anchored growth factors. Meltrin beta(ADAM19) is expressed in the peripheral nervous system, and mediates the ectodomain shedding of Neuregulin. We report here roles of Meltrin beta in the formation of the NMJ. The zone of acetylcholine receptor a mRNA distribution was broader and excess sprouting of motor nerve terminals was more prominent in Meltrin beta deficient than in wild-type embryonic diaphragms, suggesting roles of Meltrin beta in the regulation of Neuregulin. Neuregulin has various isoforms including Type I, II, and III. We isolated cDNAs encoding these three isoforms from zebrafish (Danio rerio). In situ hybridization revealed temporally and spatially regulated expression of each Neuregulin isoform during development. Moreover, we found that swimming caused dramatic upregulated expression of Neuregulin, suggesting that this gene is sensitive to stress. We are currently trying to clarify roles of Neuregulin in zebrafish muscle and nervous system by injecting morpholino oligonucleotides against each form of Neuregulin., 形態: カラー図版あり, 資料番号: AA0064297046
- Published
- 2009