The Journal of Neuroscience, April 14, 2004, ():
Endoplasmic Reticulum Export Site Formation and Function in Dendrites
J. Neurosci. Aridor et al.
24: 3770
Supplemental data
Supplemental figures
Files in this Data Supplement:
- Supplemental Fig. 1
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Figure 1. Sar1-GTP triggers the formation of ER membrane tubules in rat cortical neurons and NRK cells. Permeabilized rat cortical neurons were incubated in the presence of Sar1-GTP and in the absence (A) or presence (B) of RLC. The distribution of Sar1 (A) and Sec13 (B) were determined using confocal microscopy with specific antibodies. C, The distribution of Sar1 in permeabilized normal rat kidney cells that were incubated with Sar1-GTP only was determined by indirect IF using a specific antibody. C is a 3D reconstruction from confocal image stacks of Sar1 staining. cyt, Cytosol. Scale bars, 10 ?m.
- Supplemental Fig. 2
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Figure 2. ER tubules are consumed into vesicles on the addition of RLC. A, Permeabilized neurons incubated in the presence of Sar1-GTP to form ER tubules were rinsed and then incubated with RLC for 10 min at 37?C. The subsequent addition of RLC resulted in the consumption of ER tubule and formation of VTCs (Sec23 staining; red). A1 and A2 are higher-magnification images of the represented boxed regions in A. Arrowheads in A1 point to Sar1 tubules still in the process of dissolving. B, When Sar1-GTP is not present in the initial incubation, almost no COPII components are recruited to the ER membrane. B1 is a higher-magnification image of the represented boxed region in B. In all panels, neuronal processes were highlighted using an antibody directed against microtubulin (green). Scale bars: 10 ?m (B applies to A; A1 applies to A2, B1).
- Supplemental Fig. 3
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Figure 3. Localization of Sec61?, Sar1, and Sec13 protein to secondary and tertiary dendritic branches in rat hippocampal neurons. Hippocampal neurons were fixed and prepared for IF microscopy as described in Materials and Methods. Tertiary dendritic branch points were imaged for the presence of Sec61? (A; green), Sar1 (B; green), and Sec13 (C; green). Immunostaining patterns of these proteins sometimes colocalized with dendritic spines (phalloidin; red). Scale bar, 10 ?m.
