Rtnl1 loss does not noticeably disrupt presynaptic ER network organization. (A) Confocal sections (z steps, 1 μm) of the projections presented in the magnified areas of Fig. 2 A, showing the distribution of the ER marker tdTom::Sec61β in Type Ib muscle 1 NMJ of WT and Rtnl118 larvae. CD4::GFP labels the plasma membrane. Genotypes are Ib-GAL4, UAS-CD4::tdGFP/UAS-tdTom::Sec61β, in either a WT or Rtnl118 background. (B) Confocal sections (z steps, 1 μm) of the projections presented in the magnified areas of Fig. 2 E, showing the distribution of the ER marker Sturkopf::GFP in Type Ib muscle 1 NMJ of WT and Rtnl118 larvae. Genotypes are Ib-GAL4, UAS-Sturkopf::GFP/+, in either a WT or Rtnl118 background. Scale bars, 5 μm.