SEQUENCE AND EXPRESSION PATTERN OF THE STRA7 (GBX-2) HOMEOBOX-CONTAINING GENE INDUCED BY RETINOIC ACID IN P19 EMBRYONAL CARCINOMA-CELLS

The cDNA sequence of Stra7, a retinoic acid (RA)-inducible gene in P19 embryonal carcinoma (EC) cells, was determined. The deduced Stra7 pro tein contains a homeodomain highly similar to that of the previously d escribed chicken CHox7 gene product, and is highly conserved during ev olution, from hemichordates to vertebrates. The mouse Stra7 cDNA corre sponds to the full-length form of the 77 bp homeodomain-encoding cDNA fragment which was previously cloned and termed MMoxA or Gbx-2. Revers e-transcriptase-PCR analysis revealed the presence of Stra7/Gbx-2 tran scripts in the adult brain, spleen, and female genital tract, whereas no expression could be observed in heart, liver, lung, kidney, or test es. In situ hybridization analysis showed a restricted expression patt ern of Stra7/Gbx-2 in the three primitive germ layers during gastrulat ion. Restricted expression was also detected in the pharyngeal arches. Subsequently, there were specific expression domains in the developin g central nervous system, at the midbrain/hindbrain boundary and later in the cerebellum anlage, in certain rhombomeres, in dorsal regions o f the spinal cord, and in the developing dorsal thalamus and corpus st riatum. (C) 1995 Wiley-Liss, Inc.