Research article

Extensive molecular differences between anterior- and posterior-half-sclerotomes underlie somite polarity and spinal nerve segmentation

Daniel ST Hughes^1,2 , Roger J Keynes¹ and David Tannahill^2,3

¹Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB3 2DY, UK

²The Wellcome Trust Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK

³Cranfield Health, Cranfield University, Cranfield, Bedfordshire, MK43 0AL, UK

author email corresponding author email

BMC Developmental Biology 2009, 9:30doi:10.1186/1471-213X-9-30

Published:	22 May 2009

Abstract

Background

The polarization of somite-derived sclerotomes into anterior and posterior halves underlies vertebral morphogenesis and spinal nerve segmentation. To characterize the full extent of molecular differences that underlie this polarity, we have undertaken a systematic comparison of gene expression between the two sclerotome halves in the mouse embryo.

Results

Several hundred genes are differentially-expressed between the two sclerotome halves, showing that a marked degree of molecular heterogeneity underpins the development of somite polarity.

Conclusion

We have identified a set of genes that warrant further investigation as regulators of somite polarity and vertebral morphogenesis, as well as repellents of spinal axon growth. Moreover the results indicate that, unlike the posterior half-sclerotome, the central region of the anterior-half-sclerotome does not contribute bone and cartilage to the vertebral column, being associated instead with the development of the segmented spinal nerves.