The MATH domain, in molecular biology, is a binding domain that was defined originally by a region of homology between otherwise functionally unrelated domains, the intracellular TRAF-C domains of TRAF proteins and a C-terminal region of extracellular meprins A and B.
In cells concurrently expressing MEP1B, the meprin alpha and meprin beta subunits form disulfide dimers that interact to form membrane bound heterotetrameric meprin A .