A function for AAMP in Nod2-mediated NF-kappaB activation.

The WD40 repeat containing angio-associated migratory cell protein (AAMP) was identified as a new binding partner of the human nucleotide-binding domain, leucine rich repeat containing (NLR) family member Nod2 in a yeast two-hybrid screen. Co-immunoprecipitations from human cells verified this interaction and revealed that an internal peptide of AAMP spanning three WD40 domains was sufficient for this interaction. AAMP was found to be ubiquitously expressed in different human cell-lines and exhibited a predominant cytosolic localization in epithelial cells. Functionally, using overexpression and siRNA knock-down, we showed that AAMP modulates Nod2- and Nod1-mediated NF-kappaB activation in HEK293T cells. Taken together, our data support a new function of AAMP in regulating innate immune responses initiated by the NLR protein Nod2.