title: Murine GASP-1 N-glycosylation is not essential for its activity on C2C12 myogenic cells but alters its secretion.
abstract: OBJECTIVE
  Growth and differentiation factor-associated serum protein-1 (GASP-1) is a secreted protein known to be capable of binding and inhibiting the activity of several TGF-beta family members, including myostatin. The present study was designed to characterize murine GASP-1 post-translational modifications and to determine their influence on the biological activity of GASP-1.
  
  
  METHODS
  We describe herein the site-directed mutagenesis of single N-glycosylation sites and combinations of them in 4 mutants of murine GASP-1.
  
  
  RESULTS
  In vitro and in vivo analysis revealed that GASP-1 is a glycoprotein containing 2 N-glycans and several mucin-type O-glycans. Treatments by the recombinant murine GASP-1 protein enhance C2C12 proliferation and differentiation by inhibition of the myostatin pathway. The loss of N-glycans leads to a decrease in protein secretion rate but does not affect its ability to activate myogenesis.
  
  
  CONCLUSIONS
  Analysis of structure-function relationships of murine GASP-1 provides insights into the involvement of the carbohydrate moiety of mGASP-1 on its biological activity.
authors.affiliation: INRA, UMR1061 Génétique Moléculaire Animale - Université de Limoges, FR 3503 GEIST, Faculté des Sciences et Techniques, 87060 Limoges, France.
authors.forename: Caroline
authors.initials: C
authors.lastname: Brun
authors.forename: Olivier
authors.initials: O
authors.lastname: Monestier
authors.forename: Sébastien
authors.initials: S
authors.lastname: Legardinier
authors.forename: Abderrahman
authors.initials: A
authors.lastname: Maftah
authors.forename: Véronique
authors.initials: V
authors.lastname: Blanquet
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D019556:COS Cells; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation; D002460:Cell Line; D049109:Cell Proliferation; D002522:Chlorocebus aethiops; D006031:Glycosylation; D047908:Intracellular Signaling Peptides and Proteins; D013058:Mass Spectrometry; D051379:Mice; D016297:Mutagenesis, Site-Directed; D032446:Myoblasts / Q000166:cytology / Q000378:metabolism; D010455:Peptides / Q000032:analysis; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D014162:Transfection
chemical_list: D002352:Carrier Proteins; C479636:Gprasp1 protein, mouse; D047908:Intracellular Signaling Peptides and Proteins; D010455:Peptides; D011994:Recombinant Proteins