function tokenizeShares(
    BridgeToken _token,
    bytes32 _hash,
    bytes32[] _sigR,
    bytes32[] _sigS,
    uint8[] _sigV) public
    thresholdRequired(address(this), 0,
      abi.encodePacked(tokenizeHash(_token, _hash)),
      0, threshold, _sigR, _sigS, _sigV)
  {
    updateReplayProtection();
    token = _token;

    emit ShareTokenization(_token, _hash);
  }