FIG. 2.

CMMs are transcribed upon ubiquitous GAL4 expression during embryogenesis: in situ hybridization of embryos carrying the bxd, Mcp, or Fab7 construct. The strand-specific probes detected transcripts in the proximal-distal (d, distal; p, proximal) orientation relative to the bithorax complex. Transcripts were mostly expressed in a homogenous manner. In some lines, silencing was not completely removed, and a variegated expression pattern was observed (see Mcp line). In the absence of GAL4, minimal background expression was observed. ssRNA, single-stranded RNA.