According to MOND theorists what transmits the force of gravity?

In relativity the warping of spacetime creates the apparent force of gravity. Theories of quantum gravity claim there is a graviton boson that transmits the force. For MOND theories what allows masses to "know" to attract each other? Is it some theoretical particle, or manipulation of spacetime, or do the theories not address this? I know MOND isn't really supported by the evidence, but it would still be interesting for me to know more about it.