Figure 7

UNC-7S::GFP expressed in AVB requires UNC-9 expression in B motor neurons for proper localization to AVB:B gap junctions. (A) Diagram of anterior portion of ventral nerve cord (vnc) examined for expression of presumptive AVB:B motor neuron gap junctions. For clarity not all neuronal nuclei are represented; approximate positions of AVA and AVB (purple) posterior to the nerve ring (nr) are indicated. Motor neuron cell bodies lie along the vnc; D class motor neurons send processes dorsally to the dorsal nerve cord (dnc). The retrovesicular ganglion (rvg) is comprised of 20 neurons (including ten motor neurons) on the ventral side; the identity of neurons immediately posterior to the rvg can often be inferred by position, though some variation can occur [37]. (B) unc-7S::gfp construct expressed in unc-7(e5). UNC-7S::GFP expression enhanced with anti-GFP antibody (green); DAPI-stained cell nuclei (red). (C) In unc-4(e120) UNC-7S::GFP additionally localizes to AVB:VA motor neuron gap junctions. (D, E) UNC-7S::GFP localization is more diffuse in unc-9 daf-6 unc-7 (D), and unc-9 single mutants (E). (F) Localization is rescued in unc-9 daf-6 unc-7 by co-expressing UNC-9 in B class motor neurons (Pacr-5::unc-9). (G-I) UNC-7S::GFP expressed in AVB interneurons (Psra-11::unc-7S::gfp) in unc-7(e5) localizes to AVB:B gap junctions (G); localization is lost in unc-9 daf-6 unc-7 animals (H), but is rescued by UNC-9 expression in B motor neurons (Pacr-5::unc-9) (I). (J) UNC-9::GFP expressed in AVB (Punc-7S::unc-9::gfp) in unc-7(e5) animals fails to localize near B motor neuron cell bodies and is diffusely distributed along the ventral nerve cord.