Laboratory of Biosignal Sciences, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma 371-8512, Japan.
J Comp Neurol. 2010 Jan 10;518(2):119-36. doi: 10.1002/cne.22239.
PTPRO is a receptor-type protein tyrosine phosphatase (PTP) with a single catalytic domain in its cytoplasmic region and multiple fibronectin type III-like domains in its extracellular region. In the chick, PTPRO mRNA has been shown to be particularly abundant in embryonic brain, and PTPRO is implicated in axon growth and guidance during embryonic development. However, the temporal and spatial expression of PTPRO protein in the mammalian CNS, particularly in the juvenile and adult mammalian brain, has not been evaluated in any detail. By immunohistofluorescence analysis with a monoclonal antibody to PTPRO, we show that PTPRO is widely expressed throughout the mouse brain from embryonic day 16 to postnatal day 1, while expression is largely confined to the olfactory bulb (OB) and olfactory tubercle in the adult brain. In the OB, PTPRO protein is expressed predominantly in the external plexiform layer, the granule cell layer, and the glomerular layer (GL). In these regions, expression of PTPRO is predominant in interneurons such as gamma-aminobutyric acid (GABA)-ergic or calretinin (CR)-positive granule cells. In addition, PTPRO is expressed in GABAergic, CR-positive, tyrosine hydroxylase-positive, or neurocalcin-positive periglomerular cells in the GL. Costaining of PTPRO with other neuronal markers suggests that PTPRO is likely to be localized to the dendrites or dendritic spines of these olfactory interneurons. Thus, PTPRO might participate in regulation of dendritic morphology or synapse formation of interneurons in the adult mouse OB.
PTPRO 是一种受体型蛋白酪氨酸磷酸酶（PTP），其细胞质区域具有单个催化结构域，细胞外区域具有多个纤维连接蛋白 III 样结构域。在鸡中，已经表明 PTPRO mRNA 在胚胎脑中特别丰富，并且 PTPRO 参与胚胎发育过程中的轴突生长和导向。然而，PTPRO 蛋白在哺乳动物中枢神经系统中的时空表达，特别是在幼年和成年哺乳动物脑中，尚未得到详细评估。通过用针对 PTPRO 的单克隆抗体进行免疫组织荧光分析，我们表明 PTPRO 在从胚胎第 16 天到出生后第 1 天的整个小鼠脑中广泛表达，而在成年脑中，表达主要局限于嗅球（OB）和嗅结节。在 OB 中，PTPRO 蛋白主要在外部丛状层、颗粒细胞层和肾小球层（GL）中表达。在这些区域，PTPRO 的表达主要在 GABA 能或钙视网膜蛋白（CR）阳性的颗粒细胞等中间神经元中。此外，PTPRO 还在 GL 中的 GABA 能、CR 阳性、酪氨酸羟化酶阳性或神经钙蛋白阳性的周细胞中表达。PTPRO 与其他神经元标志物的共染色表明，PTPRO 可能定位于这些嗅中间神经元的树突或树突棘上。因此，PTPRO 可能参与调节成年小鼠 OB 中中间神经元的树突形态或突触形成。
