PUBLICATION

Souffle/Spastizin Controls Secretory Vesicle Maturation during Zebrafish Oogenesis

Authors
Kanagaraj, P., Gautier-Stein, A., Riedel, D., Schomburg, C., Cerdà, J., Vollack, N., Dosch, R.
ID
ZDB-PUB-140627-5
Date
2014
Source
PLoS Genetics   10: e1004449 (Journal)
Registered Authors
Cerdà, Joan, Dosch, Roland, Kanagaraj, Palsamy
Keywords
Oocytes, Vesicles, Zebrafish, Chorion, Oogenesis, Embryos, Lysosomes, Xenopus oocytes
MeSH Terms
  • Animals
  • Carrier Proteins/genetics*
  • Cytoplasm/metabolism
  • Female
  • Fertilization/genetics
  • Oocytes/growth & development
  • Oocytes/metabolism*
  • Oogenesis/genetics
  • Retinal Degeneration/genetics*
  • Retinal Degeneration/pathology
  • Secretory Vesicles/genetics*
  • Spastic Paraplegia, Hereditary/genetics*
  • Spastic Paraplegia, Hereditary/pathology
  • Zebrafish/genetics
  • Zebrafish/growth & development
  • Zebrafish Proteins/genetics*
  • rab GTP-Binding Proteins/genetics
  • rab GTP-Binding Proteins/metabolism
PubMed
24967841 Full text @ PLoS Genet.
Abstract
During oogenesis, the egg prepares for fertilization and early embryogenesis. As a consequence, vesicle transport is very active during vitellogenesis, and oocytes are an outstanding system to study regulators of membrane trafficking. Here, we combine zebrafish genetics and the oocyte model to identify the molecular lesion underlying the zebrafish souffle (suf) mutation. We demonstrate that suf encodes the homolog of the Hereditary Spastic Paraplegia (HSP) gene SPASTIZIN (SPG15). We show that in zebrafish oocytes suf mutants accumulate Rab11b-positive vesicles, but trafficking of recycling endosomes is not affected. Instead, we detect Suf/Spastizin on cortical granules, which undergo regulated secretion. We demonstrate genetically that Suf is essential for granule maturation into secretion competent dense-core vesicles describing a novel role for Suf in vesicle maturation. Interestingly, in suf mutants immature, secretory precursors accumulate, because they fail to pinch-off Clathrin-coated buds. Moreover, pharmacological inhibition of the abscission regulator Dynamin leads to an accumulation of immature secretory granules and mimics the suf phenotype. Our results identify a novel regulator of secretory vesicle formation in the zebrafish oocyte. In addition, we describe an uncharacterized cellular mechanism for Suf/Spastizin activity during secretion, which raises the possibility of novel therapeutic avenues for HSP research.
Genes / Markers
Figures
Expression
Phenotype
Mutation and Transgenics
Human Disease / Model Data
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping
Errata and Notes