Embryonic Development of the Cerebellum

描述(申请人提供)：我们之前的工作主要集中在胚胎小脑颗粒细胞的规范上。在这里，我们希望将注意力转向小脑的另一个主要神经元--浦肯野细胞和深层神经元。本项目的总体目标是确定四类转录因子，LIM同源结构域基因(Lhx1，Lhx3，Lhx5和Lhx9)，基本螺旋-环-螺旋基因(Math1，Mash1，Ngn1，Ngn2)，包含配对框基因(Pax2)和偶跳基因(Evx1，2)在浦肯野和深神经元祖细胞群中的地形表达，并利用这些标记来研究影响细胞命运规范的因素。局部诱导因子、BMP对基因表达和细胞规格模式的作用将在鸡胚胎和Dreher突变小鼠的基因表达研究中得到验证。首先，我们将定义小鼠和禽类胚胎中基因表达的模式，重点放在深层神经元和浦肯野细胞产生的时间段。我们将通过研究另一个项目中产生的BAC转基因小鼠的Lhx1、Lhx3、Lhx5、Lhx9、Math1、Mash1、Ngn1、Ngn2和Evx1来进一步完善我们的分析。其次，我们将研究Dreher突变小鼠，因为它遭受着BMPs的缺失，并将其用于禽类胚胎的卵子电穿孔，以确定Bmp6、BMP7和GDF7在转录因子表达模式中的作用。最后，我们将通过分析靶向零突变的小鼠和将吗啡反义寡核苷酸导入禽类胚胎来研究这些转录因子在小脑细胞分化中的作用。

DESCRIPTION (provided by applicant): Our previous work has focused on the specification of granule cells in the embryonic cerebellum. Here we wish to turn our attention to the other principal neuron of the cerebellum, the Purkinje cell and to the deep neurons. The overall aim of this project is to determine the topographic expression of four classes of transcription factors, LIM homeodomain genes (Lhx1, Lhx3, Lhx5, and Lhx9), basic helix-loop-helix genes (Math1, Mash1, Ngn1, Ngn2), Paired box containing genes (Pax2) and Even-Skipped genes (Evx1,2) in Purkinje and deep neuron progenitor cell populations in the embryonic cerebellar primordium, and to use these markers to examine factors that shape cell fate specification. The action of local inductive factors, BMPs on gene expression and cell specification patterning will be tested in gene expression studies in the chick embryo and in the Dreher mutant mouse.First, we will define patterns of gene expression in murine and avian embryos focusing on the time periods when deep neurons and Purkinje cells are generated. We will further refine our analysis by studying BAC transgenic mice for Lhx1, Lhx3, Lhx5, Lhx9, Math1, Mash1, Ngn1, Ngn2 and Evx1 generated in another project. Second, we will study the Dreher mutant mouse, because it suffers a loss of BMPs, and use in ovo electroporation in avian embryos to define the role of BMP6, BMP7 and GDF7 in transcription factor expression patterns. Finally, we will study the function of these transcription factors in cerebellar cell differentiation by analyzing mice with targeted null mutations and by transfecting morpholino antisense oligonucleotides into avian embryos.