Axis formation in annual killifish: Nodal and β-catenin regulate morphogenesis without Huluwa prepatterning

• 成果类型: Article
• 署名作者: Abitua, Philip B.; Stump, Laura M.; Aksel, Deniz C.; Schier, Alexander F.
• 署名单位: University of Washington; University of Washington Seattle; Harvard University; Harvard University; Harvard University; Massachusetts Institute of Technology (MIT); Broad Institute; Harvard University; Harvard University; University of Basel; University of Washington; University of Washington Seattle
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-12032
• DOI: 10.1126/science.ado7604
• 发表日期: 2024-06-07
• 页码: 1105-1110
• 关键词: germ-layer formation; genes; gastrulation; COMMITMENT; TRANSITION; organizer; pattern

摘要

Axis formation in fish and amphibians typically begins with a prepattern of maternal gene products. Annual killifish embryogenesis, however, challenges prepatterning models as blastomeres disperse and then aggregate to form the germ layers and body axes. We show that huluwa, a prepatterning factor thought to break symmetry by stabilizing beta-catenin, is truncated and inactive in Nothobranchius furzeri. Nuclear beta-catenin is not selectively stabilized on one side of the blastula but accumulates in cells forming the aggregate. Blocking beta-catenin activity or Nodal signaling disrupts aggregate formation and germ layer specification. Nodal signaling coordinates cell migration, establishing an early role for this signaling pathway. These results reveal a surprising departure from established mechanisms of axis formation: Huluwa-mediated prepatterning is dispensable, and beta-catenin and Nodal regulate morphogenesis.