Thibaudeau G, Holder S
Department of Biological Sciences, Mississippi State University, Mississippi State 39762, USA.
Pigment Cell Res. 1998 Feb;11(1):38-44. doi: 10.1111/j.1600-0749.1998.tb00709.x.
Many of the factors and mechanisms guiding the migration/differentiation of neural crest cells that give rise to a number of distinguishable cell types, including all dermal and epidermal pigment cells, remain unknown. The axolotl possesses three pigment cell types that differentiate according to specific developmentally programmed sequences and contribute to pigment pattern in the adult. A single lineage of the crest that becomes restricted to one of three pigment cell types gives us the opportunity to examine the existence of a neural crest stem cell population and the potential for trans-differentiation events. Interpretations of experiments involving drug-treated and mutant axolotls implicate cellular plasticity leading to observed phenotypes. We present results from recent in vitro studies designed to identify parameters influencing differentiation events of individual neural crest-derived pigment cell lineages. We demonstrate that the differentiation of xanthophores is enhanced, while that of the melanophores are inhibited in guanosine-supplemented neural crest cell cultures. Data suggest that the increase in one pigment cell population is at the expense of another, indicative of cellular plasticity. Videomicroscopy used in this study agrees with an abundance of correlative evidence supporting the hypothesis of transdifferentiation events among neural crest-derived pigment cell populations. The embryonic neural crest-derived pigment cell system is an ideal model to study differentiation of multipotential stem cells that play critical roles in patterning.
许多引导神经嵴细胞迁移/分化的因素和机制仍然未知，神经嵴细胞可产生多种可区分的细胞类型，包括所有真皮和表皮色素细胞。美西螈拥有三种色素细胞类型，它们根据特定的发育程序序列进行分化，并决定成体的色素模式。神经嵴的一个单一谱系会局限于三种色素细胞类型之一，这使我们有机会研究神经嵴干细胞群体的存在以及转分化事件的可能性。对涉及药物处理和突变美西螈的实验的解释暗示了细胞可塑性导致了观察到的表型。我们展示了最近的体外研究结果，这些研究旨在确定影响单个神经嵴衍生色素细胞谱系分化事件的参数。我们证明，在补充鸟苷的神经嵴细胞培养物中，黄色素细胞的分化增强，而黑素细胞的分化受到抑制。数据表明，一种色素细胞群体的增加是以另一种为代价的，这表明了细胞可塑性。本研究中使用的视频显微镜与大量相关证据一致，支持神经嵴衍生色素细胞群体之间转分化事件的假说。胚胎神经嵴衍生色素细胞系统是研究在模式形成中起关键作用的多能干细胞分化的理想模型。
