Fukuzawa Toshihiko, Kikuchi Yutaka
Department of Biology, Keio University, Hiyoshi 4-1-1, Kohoku-ku, Yokohama 223-8521, Japan.
Department of Biological Science, Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima, Hiroshima, 739-8526 Japan.
Tissue Cell. 2018 Oct;54:55-58. doi: 10.1016/j.tice.2018.08.003. Epub 2018 Aug 9.
Isolation and culture of Xenopus laevis neural tubes resulted in differentiation of melanophores and iridophores from neural crest cells; the differentiated melanophores and iridophores were then maintained in culture for more than 6 months. Guanosine has been reported to promote reflecting platelet formation in melanin-producing pigment cells; however, the process of pigment organellogenesis is still unclear. In the present study, unusual light-reflecting pigment cells were observed upon addition of guanosine to the neural tube culture system, which contained melanosomes specific to melanophores, and reflecting platelets specific to iridophores. Ultrastructural studies suggested that irregularly shaped reflecting platelets were formed from stage II melanosomes (the early stage of melanosome formation) in these unusual pigment cells.
非洲爪蟾神经管的分离与培养导致神经嵴细胞分化为黑素细胞和虹彩细胞；然后将分化后的黑素细胞和虹彩细胞在培养中维持了6个多月。据报道，鸟苷可促进产生黑色素的色素细胞中反光血小板的形成；然而，色素细胞器发生的过程仍不清楚。在本研究中，向神经管培养系统中添加鸟苷后，观察到了异常的反光色素细胞，该培养系统包含黑素细胞特有的黑素体和虹彩细胞特有的反光血小板。超微结构研究表明，这些异常色素细胞中不规则形状的反光血小板由II期黑素体（黑素体形成的早期阶段）形成。
