Cloning/characterization of novel downstream targets & expression/functional analysis of Hoxa2

同源盒蛋白是形态发生过程的强大调节者，也是发育过程中前后轴的重要决定因素。同源盒基因家族的大多数成员主要是通过存在一个60个氨基酸的DNA结合区，即同源结构域来识别的。同源结构域具有螺旋-转角-螺旋基序，该基序与DNA中的特定核苷酸序列结合，从而增强或抑制相应靶基因的表达。我的研究计划的长期目标是通过染色质免疫沉淀(ChIP)鉴定我实验室分离的新的Hoxa2下游靶基因(TasP和Dyrk4)的功能。特别是，我们的重点是确定它们在视觉系统和腭部发生中与Hoxa2协同发挥什么功能作用。本研究的具体目的是：1.研究HOXA2下游靶基因在体内和体外的结合特异性；2.神经视网膜中HOXA2及其下游靶基因的功能分析；3.确定HOXA2-/-小鼠腭裂发生的机制(S)。表征Hoxa2及其下游靶点的功能将破译允许Hoxa2在多个胚层作用于神经视网膜分化和腭裂形成的机制(S)。这项研究将促进我们对Hoxa2在正常视力和腭裂形成(一种常见的人类出生缺陷)中的作用的理解。

Homeobox proteins are powerful regulators of morphogenetic processes and important determinants of the anterior-posterior axis during development.  Members of the homeobox gene family are primarily recognized by the presence of a 60 amino acid DNA binding region, the homeodomain. The homeodomain has a helix-turn-helix motif that binds to specific nucleotide sequences in DNA thereby enhancing or suppressing the expression of the corresponding target genes. The long-term goal of my research program is to characterize the function of new Hoxa2 downstream target genes (Tasp and Dyrk4) isolated in my lab by chromatin immunoprecipitation (ChIP). In particular, our focus is to identify what functional role they play in concert with Hoxa2 in the visual system and in palatogenesis. The specific aims of the present proposed research are: 1. Characterize in vivo and in vitro binding specificity of Hoxa2 downstream targets; 2. Functional analysis of Hoxa2 and its downstream targets in the neural retina; and 3. Identify mechanism(s) involved in cleft palate development in Hoxa2-/-mice. Characterizing the functional role of Hoxa2 and its the downstream targets will decipher the mechanism(s) that allow Hoxa2 to act in multiple germ layers to mediate neural retina differentiation and palatogenesis. This research will advance our understanding of the role of Hoxa2 in normal vision and in cleft palate formation (a common human birth defect).