| Results demonstrate that SSAT is phosphorylated by CK 1 , in sites distinct from those phosphorylated by CK 2 . ^^^ Although CK 2 is less effective than CK 1 in phosphorylating SSAT , CK 2 phosphorylation is much more powerful in preventing binding of SSAT to mitochondrial structures . ^^^ These results suggest the involvement of CK 1 and CK 2 mediated SSAT phosphorylation in regulating the contents of polyamines and SSAT itself within subcellular compartments and implicate SSAT and polyamines as indirect modulators of progression through the cell cycle . . ^^^ |