Noncompact myelin-associated protein, also known as MP11, plays a role in myelin formation. It is a membrane protein that inhibits myelination when it is either over- or underexpressed. MP11 expression is restricted to the placenta and peripheral nervous system, where it is expressed by Schwann cells and localized to paranodes and Schmidt-Lanterman incisures (SLIs) of non-compact myelin. [].