Figure 4.

Rbfox2 is expressed in sympathetic neurons. A, Representative fluorescence image of dissociated cultured neurons from SCG. Three cells (white arrows) in image shown were injected with Rbfox2 siRNA and dextran fluorescein (green) 24 h before all cells were fixed and exposed to anti-Rbfox2 (magenta). siRNA injected cells show little anti-Rbfox2 signal (white arrows), while control cells (not injected) show strong Rbfox2 expression localized to cell nuclei (scale bars, 20 μm). B, left, Traces of calcium currents induce by voltage step to +20 mV from three different SCG neurons not injected (control, cells 1-3) and three neurons injected with dextran/fluorescein and Rbfox2 siRNA (cells 4-6). Middle, Average current density (filled symbol), median (horizontal line), 25th-75th interquartile range (box), and whiskers (range) are shown for calcium currents in control (not injected) neurons (n = 41) and in neurons injected 24 h prior with Rbfox2 siRNA (n = 22). Mean (median) ± SE in pA/pF were for control: 43.99 (41.6) ± 1.9; and for SCG siRNA injected: 56.61 (52.13) ± 6.75. Right, Cumulative frequency plot for charge density measured from control and Rbfox2 siRNA injected SCG neurons.