Role of syndecan-4 side chains in turkey satellite cell growth and development.
Syndecan-4 is a cell membrane heparan sulfate proteoglycan that is composed of a core protein and covalently attached glycosaminoglycans (GAG) and N-linked glycosylated (N-glycosylated) chains. Syndecan-4 has been shown to function independent of its GAG chains. Syndecan-4 may derive its biological function from the N-glycosylated chains due to the biological role of N-glycosylated chains in protein folding and cell membrane localization. The objective of the current study was to investigate the role of syndecan-4 N-glycosylated chains and the interaction between GAG and N-glycosylated chains in turkey myogenic satellite cell proliferation, differentiation, and fibroblast growth factor 2 (FGF2) responsiveness. The wild type turkey syndecan-4 and the syndecan-4 without GAG chains were cloned into the expression vector pCMS-EGFP and used as templates to generate syndecan-4 N-glycosylated one-chain and no-chain mutants with or without GAG chains. The wild type syndecan-4, all of the syndecan-4 N-glycosylated chain mutants were transfected into turkey myogenic satellite cells. Cell proliferation, differentiation, and responsiveness to FGF2 were measured. The overexpression of syndecan-4 N-glycosylated mutants with or without GAG chains did not change cell proliferation, differentiation, and responsiveness to FGF2 compared to the wild type syndecan-4 except that the overexpression of syndecan-4 N-glycosylated mutants without GAG chains increased cell proliferation at 48 and 72 h post-transfection. These data suggest that syndecan-4 functions in an FGF2-independent manner, and the N-glycosylated and GAG chains are required for syndecan-4 to regulate turkey myogenic satellite cell proliferation, but not differentiation.
Department of Animal Sciences, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, 44691, USA.
Yan
Y
Song
Douglas C
DC
McFarland
Sandra G
SG
Velleman
D000818:Animals; D049109:Cell Proliferation; D002478:Cells, Cultured; D006025:Glycosaminoglycans / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D016297:Mutagenesis, Site-Directed; D016133:Polymerase Chain Reaction; D032496:Satellite Cells, Skeletal Muscle / Q000378:metabolism*; D013329:Structure-Activity Relationship; D053671:Syndecan-4 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D014422:Turkeys
D006025:Glycosaminoglycans; D053671:Syndecan-4