The serpin PN1 is a feedback regulator of FGF signaling in germ layer and primary axis formation.

Research output: Contribution to journalArticle


Germ layer formation and primary axis development rely on Fibroblast growth factors (FGFs). In Xenopus, the secreted serine protease HtrA1 induces mesoderm and posterior trunk/tail structures by facilitating the spread of FGF signals. Here, we show that the serpin Protease nexin-1 (PN1) is transcriptionally activated by FGF signals, suppresses mesoderm and promotes head development in mRNA-injected embryos. An antisense morpholino oligonucleotide against PN1 has the opposite effect and inhibits ectodermal fate. However, ectoderm and anterior head structures can be restored in PN1-depleted embryos when HtrA1 and FGF receptor activities are diminished, indicating that FGF signals negatively regulate their formation. We show that PN1 binds to and inhibits HtrA1, prevents degradation of the proteoglycan Syndecan 4 and restricts paracrine FGF/Erk signaling. Our data suggest that PN1 is a negative-feedback regulator of FGF signaling and has important roles in ectoderm and head development.


  • Helena Acosta
  • Dobromir Iliev
  • Hooi Min Tan Grahn
  • Nadège Gouignard
  • Marco Maccarana
  • Julia Griesbach
  • Svende Herzmann
  • Mohsen Sagha
  • Maria Climent
  • Edgar Pera
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Developmental Biology
Original languageEnglish
Pages (from-to)1146-1158
JournalDevelopment: For advances in developmental biology and stem cells
Issue number6
Publication statusPublished - 2015
Publication categoryResearch