Investigation into the role of aquaporin-3 during gastrulation in fish embryos

Abstract

The role of aquaporins during fish embryo development is largely unknown. Here, we investigated the expression pattern and cell localization of aquaporin-3 (Aqp3) in embryos of zebrafish and killifish. In both species, transcripts encoding two Aqp3 paralogs (Aqp3a and/or -3b) are transiently The role of aquaporins during fish embryo development is largely unknown. Here, we investigated the expression pattern and cell localization of aquaporin-3 (Aqp3) in embryos of zebrafish and killifish. In both species, transcripts encoding two Aqp3 paralogs (Aqp3a and/or -3b) are transiently accumulated in migrating blastomers during gastrulation. In killifish, immunolocalization experiments revealed the presence of Aqp3a in the basolateral membrane of the cells of the enveloping layer (EVL) as well as in the membrane of ingressing blastomers at the marginal region of the blastoderm. Killifish embryos have the ability to accelerate development in response to environmental desiccation, and under these conditions aqp3a and protein levels are down-regulated. However, reduction of Aqp3a polypetides is only seen in the EVL, whereas the migrating blastomers retain the protein in the plasma membrane. These observations suggest a role of Aqp3 in cell migration as recently proposed in mammals, which is being investigated by using zebrafish embryo explant cultures and wound-healing assays