The Role of Claudin-5 on Xenopus Heart Development

Abstract

Claudin-5 is an important member of the claudin gene family. The expression of claudin-5 in the heart of Xenopus laevis was determined by whole mount in situ hybridization. RNA over expression and knock down experiments demonstrated that claudin-5 is critical for heart development. Meanwhile, claudin-5 down regulated bone morphogenetic protein 4 (BMP4) expression in early stage through upregulating chordin (chd). In addition, other pathways such as estrogen hormone and transforming growth factor-β (TGF-β) may also affect claudin-5 activity. The results show that claudin-5 plays an important role in heart development and is involved in a complex pathway of gene regulation. The mRNA expression of claudin-12, another member of claudin protein family was also determined from cleavage stage to tadpole stage by whole mount in situ hybridization.