Development Genes and Evolution

, Volume 212, Issue 9, pp 439–446

HrNodal, the ascidian nodal-related gene, is expressed in the left side of the epidermis, and lies upstream of HrPitx

  • Junji Morokuma
  • Motoko Ueno
  • Hiroshi Kawanishi
  • Hidetoshi Saiga
  • Hiroki Nishida
Short Communication

DOI: 10.1007/s00427-002-0242-3

Cite this article as:
Morokuma, J., Ueno, M., Kawanishi, H. et al. Dev Genes Evol (2002) 212: 439. doi:10.1007/s00427-002-0242-3

Abstract.

The nodal-related genes are well known for their fundamental roles during vertebrate development, including mesoderm induction, neural induction, and left-right axis formation, as several nodal-related genes show left-sided expression in mesodermal lineages. We have isolated the first non-vertebrate nodal-related gene, HrNodal, from the ascidian Halocynthia roretzi. During the late cleavage and gastrula stages, HrNodal is transiently and bilaterally expressed in several different cell lineages. Expression at the tailbud stage is observed asymmetrically in the left side, but unexpectedly only in the epidermis of the embryo. We also demonstrate the relationship of HrNodal with HrPitx, a Halocynthia homologue of the Pitx2 gene. HrNodal overexpression results in the disturbance of left-sided HrPitx expression. Our results demonstrate that left-right specification during ascidian embryogenesis involves the HrNodal gene, and that the left-sidedness of the expression is evolutionarily conserved throughout the chordate clade. Electronic Supplementary Material is available if you access this article at http://dx.doi.org/10.1007/s00427-002-0242-3. On that page (frame on the left side), a link takes you directly to the supplementary material.

Ascidian embryogenesis Nodal-related gene Pitx2 Left-right asymmetry mRNA 5′-leader trans-splicing

Copyright information

© Springer-Verlag 2002

Authors and Affiliations

  • Junji Morokuma
    • 1
  • Motoko Ueno
    • 2
  • Hiroshi Kawanishi
    • 1
  • Hidetoshi Saiga
    • 2
  • Hiroki Nishida
    • 1
  1. 1.Department of Biological Sciences, Tokyo Institute of Technology, Nagatsuta, Yokohama 226-8501, Japan
  2. 2.Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minami-ohsawa, Hachiohji, Tokyo 192-0397, Japan
  3. 3.Present address: Department of Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Aichi 444-8585, Japan