Eph/ephrin molecules are widely expressed during embryonic development, and function in a variety ofdevelopmental processes. Here we studied the roles of the Eph receptor EphA7 and its soluble form inXenopus pronephros development. EphA7 is specifically expressed in pronephric tubules at tadpole stagesand knockdown of EphA7 by a translation blocking morpholino led to defects in tubule cell differenti-ation and morphogenesis. A soluble form of EphA7 (sEphA7) was also identified. Interestingly, themembrane level of claudin6 (CLDN6), a tetraspan transmembrane tight junction protein, was dramati-cally reduced in the translation blocking morpholino injected embryos, but not when a splicing mor-pholino was used, which blocks only the full length EphA7. In cultured cells, EphA7 binds andphosphorylates CLDN6, and reduces its distribution at the cell surface. Our work suggests a role of EphA7in the regulation of cell adhesion during pronephros development, whereas sEphA7 works as anantagonist.