Biochemical and Morphological Characterization of a Guanine Nucleotide Exchange Factor ARHGEF9 in Mouse Tissues

: ARHGEF9, also known as Collybistin, a guanine nucleotide exchange factor for Rho family GTPases, is thought to play an essential role in the mammalian brain. In this study, we prepared a specific polyclonal antibody against ARHGEF9, anti-ARHGEF9, and carried out expression analyses with mouse tissues especially brain. Western blotting analyses demonstrated tissue-dependent expression profiles of ARHGEF9 in the young adult mouse, and strongly suggested a role during brain development. Immunohistochemical analyses revealed developmental stage-dependent expression profiles of ARHGEF9 in cerebral cortex, hippocampus and cerebellum. ARHGEF9 exhibited partial localization at dendritic spines in cultured hippocampal neurons. From the obtained results, anti-ARHGEF9 was found to be a useful tool for biochemical and cell biological analyses of ARHGEF9.