Figure 2. Bicistronic reporters support IRES-dependent translation in sensory neurons.

Representative static images of DRG neurons transfected with bicistronic pmCherry^myr5′Cal-eGFP^myr3′Cal (A), pmCherry^myrEMCV-eGFP^myr3′Cal (B), and pmCherry^myr5′BiP-eGFP^myr3′Cal (C) reporters are shown at 48 h post-transfection. Both mCherry (red, left panel) and eGFP (green, right panel) fluorescence is seen in the cell bodies and axons of mCherry^myrEMCV-eGFP^myr3′Cal and mCherry^myr5′BiP-eGFP^myr3′Cal expressing neurons (B,C), only the mCherry signals are seen for the mCherry^myr5′Cal-eGFP^myr-3′Cal expressing neurons (A). These data suggest that the 5′UTR of grp78/BiP mRNA but not calreticulin’s 5′UTR can function as an IRES in sensory neurons [scale bars  = 50 µm].