Function of albinism gene oca2 in non-melanocyte cell development

项目总结 眼皮肤白化病2(OCA2)基因功能丧失突变不仅导致 黑色素(黑色素)合成缺陷对皮肤颜色很重要，但也会增加 产生“副作用”或“多效性”效应的机会。多变效应的几个例子 包括感觉或神经系统发育缺陷，以及胚胎死亡 这取决于突变基因的身份。尽管多效性效应通常是 在患有诸如Waardenburg综合征和 白化病的潜在机制尚不清楚，主要是由于样本量较小。 因为色素细胞很容易透过透明的皮肤看到，卵子可以收集在 全年都很高，我们建议使用斑马鱼银质细胞来更好地了解 多效性效应就会出现。当OCA2发生突变时，斑马鱼幼体继续制造正确的 黑色素细胞、黑素细胞数量增多，但黑色素合成严重减少。 相反，银色素细胞不表达OCA2，但在不同阶段数量增加 遵循NERNAL CREST的规范。使用OCA2突变的虹膜载体作为模型，我们将 解决以下R03的具体目标：1)确定虹膜载体的发育阶段 受OCA2功能的影响。在目标1的实验中，我们将重新测试OCA2在虹膜载体中的作用 在多个附加阶段指定和检查虹膜载体的发展，包括 增殖、分化和存活--所有可能影响细胞数量的细胞事件；2) 确定OCA2是否直接或间接调节虹膜载体数量。使用我们独特的收藏 对于黑素细胞突变体，我们将确定OCA2是直接(细胞自主)还是间接(非 细胞自主地)调节虹膜基团的发育。在其他实验中，我们将 进行试验性[散装和单细胞RNA-Seq]分析，以确定这些方法是否可以 洞察OCA2的S在虹膜载体中的自主和非自主角色 发展。具体地说，这些RNA-seq数据将被分析以确定是否发生变化 在对虹膜基团发育重要的内在或外在基因的表达中， OCA2功能丧失。一旦这些实验完成，我们将有一个特征化的 多效性效应中OCA2功能的测试模型和大量的初步研究 用于为旨在阐明的R01水平研究制定适合的假设的数据 黑素细胞/黑色素与听觉/视觉/皮肤系统的机制联系 人类的发展。

Project summary Loss of function mutations in the oculocutaneous albinism 2 (oca2) gene not only lead to defects in black pigment (melanin) synthesis important for skin color, but also increase the chances of developing “side” or “pleiotropic” effects. Some examples of pleiotropic effects include deficiencies in sensory or neural system development, as well as embryonic death depending on the identity of the mutated gene. Although pleiotropic effects are commonly observed in humans with hypopigmentation disorders like Waardenburg Syndrome and albinism, the underlying mechanisms are poorly understood primarily due to low sample size. Because pigment cells are easily viewed through transparent skin and eggs can be collected in high numbers year round, we propose to use zebrafish silver cells to better understand how pleiotropic effects arise. When oca2 is mutated, zebrafish larvae continue to make the correct number of black pigment cells, melanocytes, but melanin synthesis is severely decreased. Conversely, silver pigment cells do not express oca2, but are increased in number at stages following specification from neural crest. Using oca2 mutant iridophores as a model, we will address the following R03 specific aims: 1) Determine the iridophore developmental stages impacted by oca2 function. With aim 1 experiments, we will retest the role of oca2 in iridophore specification and examine iridophore development at multiple, additional stages including proliferation, differentiation and survival – all cellular events that could impact cell number; 2) Determine if oca2 directly or indirectly regulates iridophore number. Using our unique collection of melanocyte mutants, we will determine if oca2 directly (cell-autonomously) or indirectly (non- cell autonomously) regulates iridophore development. In additional experiments, we will conduct pilot [bulk and single cell RNA-Seq] analysis to determine if these methods can provide insight into oca2’s autonomous versus non-autonomous role during iridophore development. Specifically, these RNA-seq data will be analyzed to determine whether changes in the expression of intrinsic or extrinsic genes important for iridophore development occur with oca2 loss of function. Once these experiments are complete, we will have a characterized model for testing oca2 function in pleiotropic effects and a substantial amount of preliminary data for formulating hypotheses appropriate for R01 level research aimed at elucidating mechanistic connections between melanocytes/melanin and hearing/visual/skin system development in humans.