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 2

Subcellular localization of the CXorf56 protein to the ER in microglial, BV2 cells. (a–c) Representative images from confocal immunofluorescence in BV2 cells utilizing an anti-CXorf56 antibody (a, green) and an anti-calnexin antibody, an ER-specific marker (b, red), with the overlap image shown in (c) (yellow). DAPI nuclear labeling in blue is shown in (c). A strong perinuclear colocalization between these two antibodies was evident (c). (d) Western blot analysis was carried out using BV2 whole cell lysates (left lanes) or enriched ER fractions (right lanes), and transferred proteins were probed with either the CXorf56 antibody (left panel, 1 : 500) or with the ER marker, calnexin (right panel, 1 : 1,000). The results indicated a 34 kDa immunoreactive band by the CXorf56 antibody in the ER fraction to which calnexin was also immunolabeled (right panel, 90 kDa band). Data are representative of three independent experiments.

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