Figure 1.

SFV transfection leads to overexpression of Syt1-wt and the Syt1-RQ mutant. A, B, Syt1 is located near the plasma membrane in wild type chromaffin cells (A) and is absent in syt1 null cells (B). C–E, eGFP overexpression does not change Syt1 expression in the syt1 null cell (C), whereas Syt1-wt (D) and Syt1-RQ mutant (E) transfection result in 4–5× overexpression (OE). Scale bars: 2 μm. F, Quantification of Syt1 levels by multilevel analysis. Between 3 and 14 cells were collected from two to four embryos per condition, and overall cell numbers and embryo numbers are annotated. ***p ≤ 0.001. Error bars indicate SEM. Flu. Int., Fluorescence intensity.