Fig. 5. PlexB genetically interacts with MICAL and forms a complex with PlexA. (A,B) Filleted preparations of late stage 16 embryos stained with the anti-Fasciclin II monoclonal antibody to reveal motor axons of the ISNb. (A) ISNb axons of plexB^KG00878 heterozygous embryos defasciculate properly and resemble wild-type embryos. (B) ISNb axons in embryos double heterozygous for both plexB and MICAL (Df(3R)swp2^MICAL/+; plexB^KG00878/+) often fail to defasciculate properly and do not innervate their proper muscle targets (open arrows). (C) A chart outlining the results from yeast two-hybrid interaction assays with cytoplasmic regions of PlexA and PlexB. Numbers indicate the amino acids of PlexA or PlexB that comprise each fragment. A positive interaction is indicated by a plus sign (+). The C2 region of the PlexA cytoplasmic domain (animo acids 1702-1945) and the C1 region of the PlexB cytoplasmic domain (amino acids 1402-1784) support growth and reporter gene transcription when grown on selective plates, whereas all other combinations between PlexA and PlexB do not. (D) Lysates from embryos expressing Myc-PlexB, with or without HA-PlexA, were immunoprecipitated using anti-HA antibodies and blotted with anti-HA or anti-Myc antibodies to detect the presence of HA-PlexA or Myc-PlexB, respectively. HA-PlexA immunoprecipitates from embryo lysates also contain Myc-PlexB. Scale bar in A: 10 µm for A-B.