Syndesmos(NUDT16L1) is a cytoplasmic protein which interacts specifically with the cytoplasmic domain of syndecan-4, and co-localizes with syndecan-4 in focal contacts. NUDT16L1 interacts with the focal adhesion adaptor protein paxillin. The binding of NUDT16L1 to paxillin is direct, and these interactions are triggered by the activation of protein kinase C.