Glycobiology and Extracellular Matrices
Metal Ion-dependent Heavy Chain Transfer Activity of TSG-6 Mediates Assembly of the Cumulus-Oocyte Matrix
Background: TSG-6 (TNF-stimulated gene-6)-dependent transfer of heavy chains from inter-α-inhibitor onto hyaluronan is critical for ovulation.Results: A calcium ion and chelating glutamate within TSG-6 mediate formation of the covalent heavy chain-TSG-6 intermediate.Conclusion: TSG-6 transferase activity rather than hyaluronan binding drives cumulus expansion.Significance: The role of metal ions in hyaluronan-heavy chain formation has been determined.
