Hoffman Larry F, Choy Kristel R, Sultemeier David R, Simmons Dwayne D
Department of Head & Neck Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, 90095, USA.
Brain Research Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA, 90095, USA.
J Assoc Res Otolaryngol. 2018 Feb;19(1):33-51. doi: 10.1007/s10162-017-0652-6. Epub 2018 Jan 9.
Oncomodulin (OCM, aka β-parvalbumin) is an EF-hand calcium binding protein that is expressed in a restricted set of hair cells in the peristriolar region of the mammalian utricle. In the present study, we determined the topologic distribution of OCM among hair cell phenotypes to advance our understanding of the cellular organization of the striola and the relationship of these phenotypes with characteristics of tissue polarity. The distributions of OCM-positive (OCM+) hair cells were quantified in utricles of mature C57Bl/6 mice. Immunohistochemistry was conducted using antibodies to OCM, calretinin, and β3-tubulin. Fluorophore-conjugated phalloidin was used to label hair cell stereocilia, which provided the basis for determining hair cell counts and morphologic polarizations. We found OCM expression in striolar types I and II hair cells, though the distributions were dissimilar to the native striolar type I and II distributions, favoring type I hair cells. The distribution of OCM immunoreactivity among striolar type I hair cells also reflected nonrandom distribution among type I and I phenotypes (i.e., those receiving calretinin-positive and calretinin-negative calyces, respectively). However, many OCM+ hair cells were found lateral to the striola, and within the epithelial region encompassing OCM+ hair cells, the distributions of OCM+ types I and I hair cells were similar to the native distributions of I and I in this region. Summarily, these data provide a quantitative perspective supporting the existence of different underlying factors driving the topologic expression of OCM in hair cells than those responsible for tissue polarity characteristics associated within the utricular striola, including calretinin expression in afferent calyces.
癌调蛋白（OCM，又称β-小白蛋白）是一种EF手型钙结合蛋白，在哺乳动物椭圆囊纹周区的一组特定毛细胞中表达。在本研究中，我们确定了OCM在毛细胞表型中的拓扑分布，以增进我们对纹区细胞组织的理解，以及这些表型与组织极性特征的关系。在成熟的C57Bl/6小鼠的椭圆囊中对OCM阳性（OCM+）毛细胞的分布进行了定量分析。使用针对OCM、钙视网膜蛋白和β3-微管蛋白的抗体进行免疫组织化学分析。用荧光素标记的鬼笔环肽标记毛细胞静纤毛，这为确定毛细胞数量和形态极化提供了基础。我们发现OCM在纹区I型和II型毛细胞中表达，尽管其分布与天然的纹区I型和II型分布不同，更倾向于I型毛细胞。OCM免疫反应性在纹区I型毛细胞中的分布也反映了I型和I型表型（即分别接受钙视网膜蛋白阳性和钙视网膜蛋白阴性杯状小体的毛细胞）之间的非随机分布。然而，在纹区外侧发现了许多OCM+毛细胞，在包含OCM+毛细胞的上皮区域内，OCM+I型和I型毛细胞的分布与该区域I型和I型的天然分布相似。总之，这些数据提供了一个定量的视角，支持存在不同的潜在因素驱动OCM在毛细胞中的拓扑表达，而不是那些与椭圆囊纹区相关的组织极性特征的因素，包括传入杯状小体中的钙视网膜蛋白表达。
