| Interacting proteins: P36955 and P68400 |
Pubmed |
SVM Score :0.0 |
| We found that PEDF purified from plasma is a phosphoprotein , which is extracellularly phosphorylated by protein kinase CK 2 ( CK 2 ) and to a lesser degree , intracellularly , by protein kinase A ( PKA ) . ^^^ CK 2 phosphorylates PEDF on 2 main residues , Ser 24 and Ser 114 , and PKA phosphorylates PEDF on one residue only , Ser 227 . ^^^ We found that both CK 2 and PKA phosphorylations of PEDF markedly affect its physiologic function . ^^^ The fully CK 2 phosphorylation site mutant S 24 , 114E abolished PEDF neurotrophic activity but enhanced its antiangiogenic activity , while the PKA phosphorylation site mutant S227E reduced PEDF antiangiogenic activity . ^^^ |
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| Interacting proteins: P36955 and P68400 |
Pubmed |
SVM Score :0.0 |
| This factor can act either as a neurotrophic or as an antiangiogenic factor , and we previously showed that the 2 effects of PEDF are regulated through phosphorylation by PKA and CK 2 . ^^^ Here , we studied the interplay between the PKA and CK 2 phosphorylation of PEDF , and found that a PEDF mutant mimicking the CK 2 phosphorylated PEDF can not be phosphorylated by PKA , while the mutant mimicking the PKA phosphorylated PEDF is a good CK 2 substrate . ^^^ Using triple mutants that mimic the PKA and CK 2 phosphorylated and nonphosphorylated PEDF , we found that PEDF can induce several distinct cellular activities dependent on its phosphorylation . ^^^ |
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