Secretogranin-II plays a critical role in zebrafish neurovascular modeling

J Mol Cell Biol. 2018 Oct 1;10(5):388-401. doi: 10.1093/jmcb/mjy027.

Abstract

Secretoneurin (SN) is a neuropeptide derived from specific proteolytic processing of the precursor secretogranin II (SgII). In zebrafish and other teleosts, there are two paralogs named sgIIa and sgIIb. Our results showed that neurons expressing sgIIb were aligned with central arteries in the hindbrain, demonstrating a close neurovascular association. Both sgIIb-/- and sgIIa-/-/sgIIb-/- mutant embryos were defective in hindbrain central artery development due to impairment of migration and proliferation of central artery cells. Further study revealed that sgIIb is non-cell autonomous and required for central artery development. Hindbrain arterial and venous network identities were not affected in sgIIb-/- mutant embryos, and the mRNA levels of Notch and VEGF pathway-related genes were not altered. However, the activation of MAPK and PI3K/AKT pathways was inhibited in sgIIb-/- mutant embryos. Reactivation of MAPK or PI3K/AKT in endothelial cells could partially rescue the central artery developmental defects in the sgIIb mutants. This study provides the first in vivo evidence that sgIIb plays a critical role in neurovascular modeling of the hindbrain. Targeting the SgII system may, therefore, represent a new avenue for the treatment of vascular defects in the central nervous system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Arteries / cytology
  • Arteries / embryology*
  • Cell Movement
  • Cell Proliferation
  • Embryo, Nonmammalian
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Mutation
  • Neurons / metabolism
  • Phosphatidylinositol 3-Kinases / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • Receptors, Notch / metabolism
  • Rhombencephalon / blood supply*
  • Rhombencephalon / embryology
  • Secretogranin II / genetics
  • Secretogranin II / metabolism*
  • Secretogranin II / physiology
  • Transcription Activator-Like Effector Nucleases
  • Vascular Endothelial Growth Factor A / metabolism
  • Zebrafish / embryology*
  • Zebrafish / genetics
  • Zebrafish Proteins / genetics
  • Zebrafish Proteins / pharmacology*
  • Zebrafish Proteins / physiology

Substances

  • Receptors, Notch
  • Secretogranin II
  • Vascular Endothelial Growth Factor A
  • Vegfaa protein, zebrafish
  • Zebrafish Proteins
  • scg2b protein, zebrafish
  • Proto-Oncogene Proteins c-akt
  • Extracellular Signal-Regulated MAP Kinases
  • Transcription Activator-Like Effector Nucleases