Vitronectin, an extracellular matrix protein, controls the differentiation of cerebellar granule cell precursors (CGCPs) via αvβ5 integrin, particularly in the initial stage of differentiation to granule cells. In this study, we determined whether vitronectin regulates axon specification in this initial differentiation stage of CGCPs. First, we analyzed whether vitronectin deficiency, β5 integrin knockdown (KD), and β5 integrin overexpression affect axon specification of primary cultured CGCPs. Vitronectin deficiency and β5 integrin KD inhibited axon formation, while vitronectin administrated- and β5 integrin overexpressed-neurons formed multiple axons. Moreover, KD of β5 integrin suppressed vitronectin-induced multiple axon formation. These findings indicate that vitronectin contributes to regulating axon specification via αvβ5 integrin in CGCPs. Next, we determined the signaling pathway involved in regulating vitronectin-induced axon specification. Wortmannin, an inhibitor of phosphatidylinositol 3-kinase (PI3K), inhibited vitronectin-induced multiple axon specification, and lithium chloride, an inhibitor of glyocogen synthase kinase 3 beta (GSK3β), attenuated the inhibitory effect of vitronectin-KO and β5 integrin KD on the specification of CGCPs. In addition, vitronectin induced the phosphorylation of protein kinase B (Akt) and GSK3β in neuroblastoma Neuro2a cells. Taken together, our results indicate that vitronectin plays an important factor in axon formation process in CGCPs via a β5 integrin/PI3K/GSK3β pathway.

Vitronectin是一种细胞外基质蛋白，可通过αvβ5整联蛋白控制小脑颗粒细胞前体（CGCP）的分化，特别是在分化为颗粒细胞的初始阶段。在这项研究中，我们确定玻连蛋白是否在CGCP的初始分化阶段调节轴突的规格。首先，我们分析了玻连蛋白缺乏症，β5整合素敲低（KD）和β5整合素过表达是否影响原代培养CGCP的轴突规格。玻连蛋白缺乏和β5整合素KD抑制轴突形成，而玻连蛋白和β5整合素过表达的神经元形成多个轴突。此外，β5整合素的KD抑制了玻连蛋白诱导的多轴突形成。这些发现表明玻连蛋白通过CGCP中的αvβ5整联蛋白有助于调节轴突的规格。接下来，我们确定了调控玻连蛋白诱导的轴突规格的信号传导途径。磷脂酰肌醇3激酶（PI3K）的抑制剂Wortmannin抑制玻连蛋白诱导的多重轴突规格，而糖原合成酶激酶3 beta（GSK3β）的抑制剂氯化锂减弱玻连蛋白-KO和β5整联蛋白KD的抑制作用。 CGCP的规范。此外，玻连蛋白诱导神经母细胞瘤Neuro2a细胞中蛋白激酶B（Akt）和GSK3β的磷酸化。两者合计，我们的结果表明玻连蛋白通过β5整联蛋白/ PI3K /GSK3β途径在CGCP的轴突形成过程中起重要作用。抑制玻连蛋白诱导的多轴突规格，氯化锂，糖原合成酶激酶3β（GSK3β）的抑制剂，减弱玻连蛋白-KO和β5整合素KD对CGCP规格的抑制作用。此外，玻连蛋白诱导神经母细胞瘤Neuro2a细胞中蛋白激酶B（Akt）和GSK3β的磷酸化。两者合计，我们的结果表明玻连蛋白通过β5整联蛋白/ PI3K /GSK3β途径在CGCP的轴突形成过程中起重要作用。抑制玻连蛋白诱导的多轴突规格，氯化锂，糖原合成酶激酶3β（GSK3β）的抑制剂，减弱玻连蛋白-KO和β5整合素KD对CGCP规格的抑制作用。此外，玻连蛋白诱导神经母细胞瘤Neuro2a细胞中蛋白激酶B（Akt）和GSK3β的磷酸化。两者合计，我们的结果表明玻连蛋白通过β5整联蛋白/ PI3K /GSK3β途径在CGCP的轴突形成过程中起重要作用。玻璃粘连蛋白诱导神经母细胞瘤Neuro2a细胞中蛋白激酶B（Akt）和GSK3β的磷酸化。两者合计，我们的结果表明玻连蛋白通过β5整联蛋白/ PI3K /GSK3β途径在CGCP的轴突形成过程中起重要作用。玻璃粘连蛋白诱导神经母细胞瘤Neuro2a细胞中蛋白激酶B（Akt）和GSK3β的磷酸化。两者合计，我们的结果表明玻连蛋白通过β5整联蛋白/ PI3K /GSK3β途径在CGCP的轴突形成过程中起重要作用。