First published online May 17, 2004
Development 131, 1102e (2004)
© The Company of Biologists Limited
The heart of the matter
Heart malformations are among the commonest human inborn defects. But,
although some of the genes involved in vertebrate heart morphogenesis have
been identified, little is known about the specification of heart progenitors.
On p. 2533, Satou and
co-workers report that in the ascidian Ciona savignyi, a primitive
chordate, Cs-Mesp specifies heart precursor cells.
Cs-Mesp is the sole Ciona orthologue of the vertebrate Mesp
genes, which have been implicated in heart development. The researchers show
that Cs-Mesp is specifically and transiently expressed in embryonic
heart progenitor cells in C. savignyi, and that knockdown of its
expression blocks heart development. In addition, Cs-Mesp drives the
expression of genes, including Nkx and HAND, that are
essential for vertebrate heart development. Although the ascidian heart is
simpler than the vertebrate heart, these results suggest that the mechanism
for heart specification is conserved among chordates.
Related articles in Development:
- The ascidian Mesp gene specifies heart precursor cells
- Yutaka Satou, Kaoru S. Imai, and Nori Satoh
Development 2004 131: 2533-2541.
[Abstract]
[Full Text]