Department of Head and Neck Surgery, David Geffen School of Medicine at UCLA, Box 951624, Los Angeles, CA, 90095-1624, USA.
Department of Integrative Biology and Physiology, UCLA, Los Angeles, CA, 90095, USA.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2020 Jul;206(4):623-637. doi: 10.1007/s00359-020-01418-6. Epub 2020 Apr 29.
The mammalian vestibular epithelia exhibit a remarkably stereotyped organization featuring cellular characteristics under planar cell polarity (PCP) control. PCP mechanisms are responsible for the organization of hair cell morphologic polarization vectors, and are thought to be responsible for the postsynaptic expression of the calcium-binding protein calretinin that defines the utricular striola and cristae central zone. However, recent analyses revealed that subtle differences in the topographic expression of oncomodulin, another calcium-binding protein, reflects heterogeneous factors driving the subtle variations in expression. Calbindin represents a third calcium-binding protein that has been previously described to be expressed in both hair cells and afferent calyces in proximity to the utricular striola and crista central zone. The objective of the present investigation was to determine calbindin's topographic pattern of expression to further elucidate the extent to which PCP mechanisms might exert control over the organization of vestibular neuroepithelia. The findings revealed that calbindin exhibited an expression pattern strikingly similar to oncomodulin. However, within calyces of the central zone calbindin was colocalized with calretinin. These results indicate that organizational features of vestibular epithelia are governed by a suite of factors that include PCP mechanisms as well others yet to be defined.
哺乳动物前庭上皮表现出显著的刻板组织，其特征是在平面细胞极性 (PCP) 控制下的细胞特征。PCP 机制负责毛细胞形态极性向量的组织，并且被认为负责钙结合蛋白 calretinin 的突触后表达，该蛋白定义了椭圆囊纹和嵴中央区。然而，最近的分析表明，钙结合蛋白 oncomodulin 的拓扑表达的细微差异反映了驱动表达细微变化的异质因素。钙结合蛋白 calbindin 代表另一种先前被描述为在靠近椭圆囊纹和嵴中央区的毛细胞和传入 calyx 中表达的第三种钙结合蛋白。本研究的目的是确定 calbindin 的拓扑表达模式，以进一步阐明 PCP 机制可能在多大程度上对前庭神经上皮的组织施加控制。研究结果表明，calbindin 的表达模式与 oncomodulin 非常相似。然而，在中央区的 calyx 中，calbindin 与 calretinin 共定位。这些结果表明，前庭上皮的组织特征受一系列因素控制，包括 PCP 机制以及其他尚未确定的因素。
