Fig. 3. The enpp and the lipidic receptors, the lpar and s1pr, gene family members are expressed in the pronephros.

Developing pronephric anlagen or pronephric tubules were dissected as indicated, from whole X. laevis embryos and total RNA extracted. RT-PCR was performed on pronephric dissected tissues and control whole embryos along with negative and linearity controls. a Comparative expression pattern of the enpp genes and pronephric and muscle marker genes controlling the quality of the dissections. b Comparative expression profile of the lpa receptors. c Comparative expression profile of the s1pr genes.