Fig. 3. The dimB^- mutant exhibits DIF-1 signalling morphological defects. (A) Schematic of the dimB gene and disruption vector. The predicted DimB protein contains 1809 amino acids. Regions of low complexity [poly glutamine (Q) and poly asparagine (N) tracts] and the basic-leucine zipper (bZIP) domain are highlighted. The dimB disruption vector was generated by in vitro transposition of sequences containing the tetracycline resistance gene (for selection in bacteria) and the blasticidin resistance gene into the dimB-coding sequence. (B) Developmental morphology of dimB^- mutant cells. (C) dimB^- and dimAB^- double-mutant cells form long thin slugs compared with wild type (AX4).