Changes in the distribution of extracellular matrix components during neural crest development in <i>Xiphophorus</i> spp. embryos

Abstract

The changes in distribution of chondroitin sulfate proteoglycans (CSs) and fibronectin (FN), two major components of the extracellular matrix (ECM), are described during the development and migration of neural crest cells in two Xiphophorus species offish, X. helleri (swordtail) and X. maculatus (platyfish), using immunohistochemistry. A detailed description of the developmental changes in HNK-1-positive ECM components is also provided and compared with those of CSs and FN. HNK-1 antigen was also used as a marker for the neural crest cells. Weak staining for CSs, FN, and HNK-1-positive ECM was present in the neural crest cell migration pathways prior to migration of the cells. The level of staining increased dramatically during migration of these cells and decreased again after migration was nearly completed. Staining for CSs was more widespread than staining for FN, while the HNK-1 staining pattern was more clearly restricted to the migratory pathways than those seen with the other two antibodies. The correlation between the spatiotemporal relationship of these ECM components and the segregation and migration of neural crest cells suggests that these ECM molecules may be involved in both initiating and guiding the migration of neural crest cells in these fish. The HNK-1-positive ECM may play a more critical role than CSs and FN.