CARMA1 is phosphorylated at serines 559, 644, and 652 by Protein Kinase C beta (PKC-beta) (Sommer et al. 2005). CARMA1 is constitutively oligomerized (Tanner et al. 2007) and most CARMA1 in unstimulated cells is cytosolic (Sommer et al. 2005, Tanner et al. 2007), though a portion is constitutively associated with the plasma membrane (Gaide et al. 2002, Sommer et al. 2005). After phosphorylation, CARMA1 is associated with lipid rafts in the plasma membrane (Sommer et al. 2005). Note that some publications refer to CARMA1 with a different N-terminal methionine that is 7 amino acids shorter. In this case the phosphorylated serines are 552, 537, and 645.