Int. J. Dev. Biol. 49: 401 - 408 (2005)
doi: 10.1387/ijdb.052005dl
© UPV/EHU Press

The role of XTRAP-gamma in Xenopus pronephros development

Dong-hui Li1, Techuan Chan2, Reiko Satow3, Shinji Komazaki4, Kouhei Hashizume1 and Makoto Asashima*,2

1Department of Pediatric Surgery and Oncology, Graduate School of Medicine, The University of Tokyo, Japan, 2Life Sciences, ICORP Project (JST), Graduate School of Arts and Sciences, The University of Tokyo, Japan, 3Dept. Biological Sciences, The University of Tokyo, Tokyo, Japan and 4Dept. Anatomy, Saitama Medical University, Saitama, Japan

ABSTRACT We isolated and characterized the Xenopus translocon-associated protein XTRAP-gamma, one of four subunits of the translocon-associated protein complex. TRAP has been proposed to aid the translocation of nascent polypeptides into the lumen of the endoplasmic reticulum, but this has not been demonstrated until now. XTRAP-gamma was specifically expressed in the pronephros tubules of Xenopus laevis from stage 25 during kidney development. Antisense morpholino oligonucleotide-mediated knockdown of XTRAP-gamma suppressed tubulogenesis and decreased expression of the pronephros marker genes Pax-2 and Wnt-4. XTRAP-gamma morpholinos also inhibited differentiation of the pronephros in activin/retinoic acid-treated animal caps. We conclude that XTRAP-gamma plays an important role in the process of pronephros differentiation.

Keywords:

XTRAP-gamma, Xenopus laevis, pronephros, Pax-2, Wnt-4

*Corresponding author e-mail: asashi@bio.c.u-tokyo.ac.jp