Abstract
Purpose: :
It remains unknown whether heparan sulfate is essential for ocular development although it has been known that heparan sulfate/heparan sulfate proteoglycans bind to numerous kinds of growth factors and morphogens that play critical roles in the ocular development. We investigated the roles of heparan sulfate/ heparan sulfate proteoglycans in the development of the anterior segment of the eye.
Methods: :
We disrupted the gene of EXT1 in mice because EXT1 is an indispensable enzyme for the synthesis of heparan sulfate. Using the Cre–loxP approach, EXT1 gene alleles were knocked out conditionally in the neural crest cells during embryogenesis because the migrating neural crest cells are the main components of the anterior segment in mammalian eyes.
Results: :
The heparan sulfate–deficient mice exhibited various anomalies in the anterior eye segment including coloboma iridis. The anomalies in the neural crest cell–derived tissues resembled the anomalies associated with one of human developmental glaucomatous diseases, Peter’s anomaly.
Conclusions: :
The development of the anterior segment requires heparan sulfate/heparan sulfate proteoglycans. It is possible that disturbed expression of heparan sulfate/heparan sulfate proteoglycans may be involved in the onset of developmental glaucoma.
Keywords: pathology: experimental • proteoglycans/glycosaminoglycans • transgenics/knock-outs