Warner Stephen J, Hutson Mary R, Oh Seung-Ha, Gerlach-Bank Lisa M, Lomax Margaret I, Barald Kate F
Kresge Hearing Research Institute, Department of Otolaryngology/Head-Neck Surgery, University of Michigan Medical School, Ann Arbor, Michigan 48109, USA.
Dev Dyn. 2003 Apr;226(4):702-12. doi: 10.1002/dvdy.10262.
ZIC genes, vertebrate homologues of the Drosophila pair-rule gene odd-paired (opa), function in embryonic pattern formation, in the early stages of central nervous system neurogenesis and in cerebellar maturation. Mouse Zic genes are expressed in restricted, and in some cases overlapping, patterns during development, particularly in the central and peripheral nervous systems. We identified chick ZIC2 in a differential display analysis of the auditory system designed to find genes up-regulated after noise trauma. In this study, we examined the expression of chick ZIC1, ZIC2, and ZIC3 by in situ hybridization in normal inner ear development and in the tissues that influence its development, including the hindbrain, the neural crest, and the periotic mesenchyme. Between Hamburger and Hamilton stages 13 and 24, all three ZIC genes were found in the dorsal periotic mesenchyme adjacent to the developing inner ear. ZIC1 mRNA was expressed in the otocyst epithelium between stages 12 and 24, in some sensory tissue, as well as in a striped pattern in the floorplate of the hindbrain that appears to be complementary to that of Chordin, a gene known to regulate ZIC expression in frogs. Chick ZIC genes are also expressed in the neuroectoderm, paraxial mesenchyme, brain, spinal cord, neural crest, and/or the overlying ectoderm as well as the limb buds. In general, ZIC1 and ZIC2 expression patterns overlapped, although ZIC2 expression was less robust; ZIC3 expression was minimal. These observations suggest that ZIC genes, in addition to their known roles in brain development, may play an important role in the development of the chick inner ear.
ZIC基因是果蝇成对规则基因odd-paired（opa）的脊椎动物同源物，在胚胎模式形成、中枢神经系统神经发生的早期阶段以及小脑成熟过程中发挥作用。小鼠ZIC基因在发育过程中以受限且在某些情况下重叠的模式表达，特别是在中枢和外周神经系统中。我们在旨在寻找噪声损伤后上调基因的听觉系统差异显示分析中鉴定出了鸡ZIC2。在本研究中，我们通过原位杂交检测了鸡ZIC1、ZIC2和ZIC3在正常内耳发育以及影响其发育的组织（包括后脑、神经嵴和耳周间充质）中的表达。在Hamburger和Hamilton第13至24阶段之间，在内耳发育部位相邻的背侧耳周间充质中发现了所有这三个ZIC基因。ZIC1 mRNA在第12至24阶段的耳囊中表达，在一些感觉组织中也有表达，并且在后脑底板中呈条纹状表达，这似乎与已知在青蛙中调节ZIC表达的基因Chordin的表达互补。鸡ZIC基因也在神经外胚层、轴旁间充质、脑、脊髓、神经嵴和/或覆盖的外胚层以及肢芽中表达。一般来说，ZIC1和ZIC2的表达模式重叠，尽管ZIC2的表达较弱；ZIC3的表达最少。这些观察结果表明，ZIC基因除了在脑发育中已知的作用外，可能在鸡内耳发育中起重要作用。
