The oligomeric status of syndecan-4 regulates syndecan-4 interaction with α-actinin

Youngsil Choi, Seungin Kim, Junghyun Lee, Sung gun Ko, Weontae Lee, Inn Oc Han, Anne Woods, Eok Soo Oh

Research output: Contribution to journalArticlepeer-review

26 Citations (Scopus)


Syndecan-4, a cell surface heparan sulfate proteoglycan, is known to regulate the organization of the cytoskeleton, and oligomerization is crucial for syndecan-4 function. We therefore explored a possible regulatory effect of syndecan-4 oligomerization on the cytoskeleton. Glutathione-S-transferase-syndecan-4 proteins were used to show that syndecan-4 interacted specifically with α-actinin, but not paxillin, talin, and vinculin. Interestingly, only dimeric, and not monomeric, recombinant syndecan-4 interacted with α-actinin in the presence of phosphatidylinositol 4,5-bisphosphate (PIP2), and PIP2 potentiated the interaction of both the cytoplasmic domain syndecan-4 peptide and recombinant syndecan-4 proteins with α-actinin, implying that oligomerization of syndecan-4 was important for this interaction. Consistent with this notion, α-actinin interaction was largely absent in syndecan-4 mutants defective in transmembrane domain-induced oligomerization, and α-actinin-associated focal adhesions were decreased in rat embryo fibroblasts expressing mutant syndecan-4. Besides, this interaction was consistently lower with the phosphorylation-mimicking syndecan-4 mutant S183E which is known to destabilize the oligomerization of the syndecan-4 cytoplasmic domain. Taken together, the data suggest that the oligomeric status of syndecan-4 plays a crucial role in regulating the interaction of syndecan-4 with α-actinin.

Original languageEnglish
Pages (from-to)807-815
Number of pages9
JournalEuropean Journal of Cell Biology
Issue number10
Publication statusPublished - 2008 Oct

Bibliographical note

Funding Information:
This work was supported by Korea Research Foundation Grant (KRF-2002-CP0327 to E.S. Oh) and in part by Grant No. R15-2006-020 from the National Core Research Center (NCRC) program of the Ministry of Science & Technology (MOST) and the Korea Science and Engineering Foundation (KOSEF) through the Center for Cell Signaling & Drug Discovery Research at Ewha Womans University.

All Science Journal Classification (ASJC) codes

  • Pathology and Forensic Medicine
  • Histology
  • Cell Biology


Dive into the research topics of 'The oligomeric status of syndecan-4 regulates syndecan-4 interaction with α-actinin'. Together they form a unique fingerprint.

Cite this