Hyaluronan Mediated Motility Receptor (HMMR)

RHAMM) was originally discovered as a soluble protein that altered migratory cell behavior and bound to hyaluronan,RHAMM is less well studied than the main hyaluronan (HA) receptor, CD44. In contrast to CD44 and other cell-surface receptors which contain the classical membrane spanning domain and signal sequence for secretion from the endoplasmic reticulum / Golgi complex, RHAMM does not contain a membrane spanning domain nor does the mRNA transcript contain a signal sequence.

RHAMM normally is localized inside the cell and is only release by certain, poorly defined stimuli. The transport of RHAMM to the extracellular space still is unclear but may involve transport channels or proteins, flippase activity, or exocytosis.