fushi tarazu (ftz) encodes a HOX-like (HOXL) homeobox transcription factor and is a pair-rule segmentation gene expressed in seven stripes in early embryos. The ftz protein interacts with the obligate partner ftz-
f1, a nuclear receptor, to directly activate a set of target genes involved in segment development, including segment polarity genes such as en and ftz itself. ftz is also expressed and required in the developing central nervous system.