First published online July 21, 2003
Development 130, e1702 (2003)
Copyright © 2003 The Company of Biologists Limited
Combinatorial specification of motoneurons
Somatic and ventral motoneurons (sMNs and vMNs, respectively) are both
required for the central control of vertebrate body movement and homeostasis.
But although much is known about how the differentiation of sMNs is
controlled, less is known about vMN specification in the developing hindbrain.
On p. 4149, Pattyn
and his colleagues describe how the Nkx6 and Nkx2 classes of homeodomain
proteins have complementary roles in vMN specification in mice and chicks.
While Nkx2.2 is sufficient to induce vMNs, Nkx6 proteins are not needed for
vMN generation but instead prevent these cells from differentiating into
interneurons and direct later aspects of their differentiation. The authors
also show that Nkx6 proteins and the motoneuron determinant Olig2 act in
parallel in sMN differentiation, a result that leads them to conclude that sMN
and vMN cell fate specification requires a combination of transcription
factors rather than a single master regulator.
Related articles in Development:
- Complementary roles for Nkx6 and Nkx2 class proteins in the establishment of motoneuron identity in the hindbrain
- Alexandre Pattyn, Anna Vallstedt, Jose M. Dias, Maike Sander, and Johan Ericson
Development 2003 130: 4149-4159.
[Abstract]
[Full Text]