Figure 8. Exogenously expressed ERES markers are targeted to axons.
(A–C) Localization of endogenous and over-expressed Yip1a, a membrane ERES marker, in the developing axon. (A) Untransfected early stage 3 neurons were stained using phalloidin (A1; red in A3) and an antibody directed against Yip1a (A2; green in A3). (B) Neuronal cultures transfected with a GFP-Yip1a (B2; green in B3) construct on 2 DIV, were fixed and stained with phalloidin (B1; red in B3) at 3 DIV. (C) Neuron cultures were transfected at 2 DIV with Myc-Yip1, fixed at 3 DIV, and stained for over-expressed Myc-Yip1 (C1; red in C3) and Sec23 (C2; green in C3) or Sar1 (c2a; green in c3a). The inset image c3b mag. is a blowup of the designated region in C3 (c3b). (D) Shows a 2 DIV rat hippocampal neuron, which was transfected prior to plating, expressing the ER marker mEmerald-KDEL. Bars equal 10 µm.