Differential effects of N-linked glycosylation of Vstm5 at multiple sites on surface expression and filopodia formation

PLoS One. 2017 Jul 26;12(7):e0181257. doi: 10.1371/journal.pone.0181257. eCollection 2017.

Abstract

V-set and transmembrane domain-containing protein 5 (Vstm5), a newly characterized small membrane glycoprotein, can induce membrane protrusions in various cells. Vstm5 can modulate both the position and complexity of central neurons by altering their membrane morphology and dynamics. In this study, we investigated the significance of glycosylation in the expression and function of Vstm5. Four N-linked glycosylation sites (Asn43, Asn87, Asn101, and Asn108) are predicted to be located in the extracellular N-terminus of mouse Vstm5. Although all four sites were glycosylated, their functional roles may not be identical. N-glycosylation at multiple sites affects differentially the function of Vstm5. Glycosylation at individual sites not only played essential roles in surface expression of Vstm5 but also in the formation of neuronal dendritic filopodia. These results indicate that N-linked glycosylation at multiple sites plays important roles by differentially influencing the expression, targeting, and biological activity of Vstm5.

MeSH terms

  • Animals
  • Asparagine / genetics
  • Asparagine / metabolism*
  • Binding Sites / genetics
  • COS Cells
  • Cell Membrane / metabolism
  • Dendrites / metabolism*
  • Glycosylation
  • HEK293 Cells
  • Humans
  • Immunoblotting
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Mice
  • Microscopy, Confocal
  • Mutation
  • Neurons / metabolism*
  • Pseudopodia / genetics
  • Pseudopodia / physiology*

Substances

  • Membrane Proteins
  • V-set and transmembrane domain containing 5 protein, mouse
  • Asparagine

Grants and funding

This work was supported by the grant for National Leading Research Laboratory (2011-0028665) from the National Research Foundation of Korea (study design, and data collection and analysis) and by the grant for Bio-imaging Research Center by GIST in 2016 and 2017 (data collection and analysis, decision to publish, and preparation of the manuscript).