Vitronectin promotes the progress of the initial differentiation stage in cerebellar granule cells

• Published in: Molecular and cellular neuroscience 2016-01, Vol.70, p.76-85
• Main Authors: Hashimoto, Kei, Sakane, Fumi, Ikeda, Natsumi, Akiyama, Ayumi, Sugahara, Miyaka, Miyamoto, Yasunori
• Format: Article
• Language: English
• Subjects: Animals; Cell Differentiation - physiology; Cell Proliferation - physiology; Cerebellar granule cell; Cerebellum - cytology; Cerebellum - metabolism; Contactin 2 - genetics; Contactin 2 - metabolism; Development of the cerebellum; Differentiation; Mice; Mice, Knockout; Migration; Nerve Tissue Proteins - genetics; Nerve Tissue Proteins - metabolism; Neurons - cytology; Neurons - metabolism; Nuclear Proteins - genetics; Nuclear Proteins - metabolism; Vitronectin; Vitronectin - genetics; Vitronectin - metabolism
• ISSN: 1044-7431; 1095-9327
• DOI: 10.1016/j.mcn.2015.11.013

Vitronectin (VN), which is an extracellular matrix protein, is known to be involved in the proliferation and differentiation of primary cultured cerebellar granule cell precursors (CGCPs); however, the effect of VN is not fully understood. In this study, we analyzed the effects of VN loss on the proliferation and differentiation of CGCPs in VN knockout (VNKO) mice in vivo. First, immunohistochemistry showed that VN was distributed in the region from the inner external granule layer (iEGL) through the internal granule layer (IGL) in wild-type (WT) mice. Next, we observed the formation of the cerebellar cortex using sagittal sections of VNKO mice at postnatal days (P) 5, 8 and 11. Loss of VN suppressed the ratio of NeuN, a neuronal differentiation marker, to positive cerebellar granule cells (CGCs) in the external granule layer (EGL) and the ratio of CGCs in the IGL at P8, indicating that the loss of VN suppresses the differentiation into CGCs. However, the loss of VN did not significantly affect the proliferation of CGCPs. Next, the effect of VN loss on the initial differentiation stage of CGCPs was examined. The loss of VN increased the expression levels of Transient axonal glycoprotein 1 (TAG1), a marker of neurons in the initial differentiation stage, in the cerebella of VNKO mice at P5 and 8 and increased the ratio of TAG1-positive cells in the primary culture of VNKO-derived CGCPs, indicating that the loss of VN accumulates the CGCPs in the initial differentiation stage. Taken together, these results demonstrate that VN promotes the progress of the initial differentiation stage of CGCPs. •In VNKO mice, the number of CGCs in the IGL is reduced at P8.•VN does not affect the proliferation of CGCPs in vivo.•Loss of VN inhibits the progress of the initial differentiation stage of CGCPs.•Migration of CGCPs from the EGL to the IGL is suppressed in VNKO mice.