AMPHIBMP2 4, AN AMPHIOXUS BONE MORPHOGENETIC PROTEIN CLOSELY-RELATED TO DROSOPHILA DECAPENTAPLEGIC AND VERTEBRATE BMP2 AND BMP4 - INSIGHTS INTO EVOLUTION OF DORSOVENTRAL AXIS SPECIFICATION/

Amphioxus AmphiBMP2/4 appears to be a single gene closely related to v ertebrate BMP2 and BMP4. In amphioxus embryos, the expression patterns of AmphiBMP2/4 suggest patterning roles in the ectodermal dorsoventra l axis (comparable to dorsoventral axis establishment in the ectoderm by Drosophila decapentaplegic and vertebrate BMP4). In addition AmphiB MP2/4 may be involved in somite evagination, tail bud growth, pharynge al differentiation (resulting in club-shaped gland morphogenesis), hin dgut regionalization, differentiation of olfactory epithelium, pattern ing of the anterior central nervous system, and establishment of the h eart primordium, One difference between the developmental role of amph ioxus AmphiBMP2/4 and vertebrate BMP4 is that the former does not appe ar to be involved in the initial establishment of the dorsoventral pol arity of the mesoderm, Dev. Dyn. 1998;213:130-139. (C) 1998 Wiley-Liss , Inc.