XNKX-2.5, A XENOPUS GENE-RELATED TO NKX-2.5 AND TINMAN - EVIDENCE FORA CONSERVED ROLE IN CARDIAC DEVELOPMENT

We have isolated a Xenopus homeodomain sequence, XNkx-2.5, which shows significant similarity to mouse Nkx-2.5 and to the Drosophila tinman gene product. In Drosophila, tinman, is required for formation of the heart and visceral mesoderm structures. In situ hybridization studies show that XNkx-2.5 is expressed in the heart region during early Xenop us development and later is also expressed in gut tissue. The observed similarity of sequences and expression patterns suggests that the reg ulatory mechanisms underlying heart formation may be conserved between distant species. (C) 1994 Academic Press, Inc.