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Updated: Oct 20, 2026

Three and Four-Dimensional Visualization and Analysis Approaches to Study Vertebrate Axial Elongation and Segmentation
Published on: February 28, 2021
Segmental expression of aggrecan in the non-segmented perinotochordal sheath underlies normal segmentation of the
1Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta 30912, USA.
Abstract:
The embryonic vertebral column is derived from the unsegmented axial mesenchyme surrounding the notochord, and its development and differentiation are influenced by the notochord. The role of cartilage in determining the ultimate pattern of the segmental skeleton has been well documented, but a gene whose segmental expression corresponds to the pattern of the developing skeleton has yet to be identified. We show that chick aggrecan is initially expressed within the entire length of the notochord, and as development proceeds, aggrecan expression becomes restricted to the surrounding perinotochordal sheath in a segmental pattern, mirroring the differentiated somite pattern.
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