A Fragment of Apolipoprotein E4 Leads to the Downregulation of a CXorf56 Homologue, a Novel ER-Associated Protein, and Activation of BV2 Microglial Cells

Figure 4

Downregulation of the CXorf56 protein leads to morphological changes in BV2 microglia cells. (a–d) BV2 cells were untreated (a) or treated for 5 hours with scrambled negative control siRNA (b), siRNA2 (c), or siRNA3 targeting the open reading frame CXorf56 (d). Following treatment, bright-field, phase-contrast images were captured. In contrast to untreated or cells treated with the siRNA negative control, cells treated with targeted siRNAs led to changes in morphology from round, compact cells to cells that were flattened and extended long pseudopods (arrowheads, c and d) and or were highly vacuolized (arrows, c and d). Scale bars represent 10 μm. (e, f) Quantification using the ImageJ software showing percent of cells with pseudopods was significantly increased following treatment with either siRNA2 or 3 (e, blue and red bars) as was the length of pseudopods per cell (f, blue and red bars). In (e), denotes significant difference between scrambled siRNA negative control (orange bar) and siRNA(2) (blue bar), ; # denotes significant difference between scrambled siRNA negative control (orange bar) and siRNA(3) (red bar), . In (f), denotes significant difference between scrambled siRNA negative control (orange bar) and siRNA(2) (blue bar), ; # denotes significant difference between scrambled siRNA negative control (orange bar) and siRNA(3) (red bar), . Data in (e) and (f) are representative of 4 independent

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