Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan.
PLoS One. 2011;6(8):e23078. doi: 10.1371/journal.pone.0023078. Epub 2011 Aug 2.
The zona pellucida (ZP) domain is part of many extracellular proteins with diverse functions from structural components to receptors. The mammalian β-tectorin is a protein of 336 amino acid residues containing a single ZP domain and a putative signal peptide at the N-terminus of the protein. It is 1 component of a gel-like structure called the tectorial membrane which is involved in transforming sound waves into neuronal signals and is important for normal auditory function. β-Tectorin is specifically expressed in the mammalian and avian inner ear.
METHODOLOGY/PRINCIPAL FINDINGS: We identified and cloned the gene encoding zebrafish β-tectorin. Through whole-mount in situ hybridization, we demonstrated that β-tectorin messenger RNA was expressed in the otic placode and specialized sensory patch of the inner ear during zebrafish embryonic stages. Morpholino knockdown of zebrafish β-tectorin affected the position and number of otoliths in the ears of morphants. Finally, swimming behaviors of β-tectorin morphants were abnormal since the development of the inner ear was compromised.
CONCLUSIONS/SIGNIFICANCE: Our results reveal that zebrafish β-tectorin is specifically expressed in the zebrafish inner ear, and is important for regulating the development of the zebrafish inner ear. Lack of zebrafish β-tectorin caused severe defects in inner ear formation of otoliths and function.
透明带（ZP）结构域是具有多种功能的许多细胞外蛋白的一部分，从结构成分到受体。哺乳动物的β-张力蛋白是一种由 336 个氨基酸残基组成的蛋白质，含有一个 ZP 结构域和一个假定的蛋白质 N 端信号肽。它是一种称为听膜的凝胶状结构的 1 个组成部分，该结构参与将声波转化为神经元信号，对于正常听觉功能很重要。β-张力蛋白特异性地在内耳的哺乳动物和禽类中表达。
方法/主要发现：我们鉴定并克隆了编码斑马鱼β-张力蛋白的基因。通过整体原位杂交，我们证明了β-张力蛋白信使 RNA 在斑马鱼胚胎发育过程中在内耳的耳泡和特化的感觉斑中表达。斑马鱼β-张力蛋白的 Morpholino 敲低影响了 Morphants 耳朵中耳石的位置和数量。最后，由于内耳发育受到影响，β-张力蛋白 Morphants 的游泳行为异常。
结论/意义：我们的结果表明，斑马鱼β-张力蛋白特异性地在内耳中表达，对于调节斑马鱼内耳的发育很重要。缺乏斑马鱼β-张力蛋白导致耳石和功能在内耳形成中出现严重缺陷。
