SPG21

Maspardin is a protein that in humans is encoded by the SPG21 gene.

The protein encoded by this gene was identified by a two-hybrid screen using CD4 as the bait. It binds to the hydrophobic C-terminal amino acids of CD4 which are involved in repression of T cell activation. The interaction with CD4 is mediated by the noncatalytic alpha/beta hydrolase fold domain of this protein. It is thus proposed that this gene product modulates the stimulatory activity of CD4.