Cadherins in the Developing Zebrafish Inner Ear

描述（由申请人提供）：我们建议使用斑马鱼（Danio rerio）作为模型系统检查内耳发育。斑马鱼已经成为一种强大的实验生物体，因为它易于在发育生物学和遗传研究中使用。斑马鱼的内耳与其他脊椎动物的内耳基本相同：一个封闭的上皮结构，有三个连通的腔室和三个半规管。然而，在鱼耳中没有发现耳蜗或蜗管。感觉斑位于腔室和通道内，由毛细胞和支持细胞组成。毛细胞与将信号传递到大脑的平衡声神经节（SAG）细胞突触。在感觉块上方的基质中的耳石允许硬骨鱼检测机械刺激，包括线性和旋转加速度，重力和声音。钙粘蛋白细胞粘附分子控制各种发育过程，包括神经系统中的细胞分选、分化和神经突形成等过程。我们建议，以确定在内耳和SAG的发展过程中的钙粘蛋白细胞粘附分子的作用。本研究的目的有三：（1）确定钙粘蛋白在斑马鱼内耳发育过程中的表达模式;（2）确定钙粘蛋白在内耳发育过程中的功能;（3）确定Pax-2基因功能对钙粘蛋白在耳基板诱导、内耳发育和听神经节（SAG）形成过程中表达的影响。

DESCRIPTION (provided by applicant): We propose to examine inner ear development using zebra fish, Danio rerio, as a model system. Zebra fish has emerged as a powerful experimental organism because of the ease of use in developmental biology and genetic studies. The zebra fish inner ear is essentially the same as that in other vertebrates: a closed epithelial structure with three communicating chambers and three semicircular canals. However, no cochlea or cochlear duct is found in the fish ear. Sensory patches are found within the chambers and canals, composed of hair cells and supporting cells. Hair cells synapse with statoacoustic ganglion (SAG) cells that relay the signals to the brain. Otoliths in the matrix above the sensory patches allow teleost fish to detect mechanical stimulation, including linear and rotational acceleration, gravity and sound. Cadherin cell adhesion molecules control a variety of developmental processes, including processes like cell sorting, differentiation and neurite formation in the nervous system. We propose to determine the role of cadherin cell adhesion molecules during the development of the inner ear and SAG. Three specific aims will be employed; (1) determine expression pattems of cadherins in the inner ear of developing zebra fish; (2) determine the function of cadherins during inner ear development; and (3) determine the effects of Pax-2 gene function on cadherin expression during otic placode induction, inner ear development and statoacoustic ganglion (SAG) formation.