Cyclic modulation of cytoskeleton assembly-disassembly by the ATP.Mg-dependent protein phosphatase activator (kinase FA).
The ATP.Mg-dependent protein phosphatase activating factor (FA) has been identified as a microtubule protein kinase and as a microtubule protein phosphatase activator. FA could phosphorylate microtubule-associated tau protein up to 4 moles of phosphates per mole of protein. However, more than 80% of the phosphates in 32P-tau phosphorylated by FA could be removed by ATP.Mg-dependent protein phosphatase and the tau phosphatase activity was FA-dependent. Functional study further revealed that as a tau kinase, FA could phosphorylate tau and thereby inhibits cross-linking copolymerization of tau with tubulin and actin filaments whereas as a tau phosphatase activating factor, FA could promote copolymerization of tau with tubulin and actin filaments. Taken together, the results provide evidence that a cyclic modulation of cytoskeleton assembly-disassembly can be controlled by FA, representing an efficient cyclic cascade mechanism for rapid structural and functional regulation of cytoskeletal system in the central nervous system.
Yang
S D
SD
Institute of Biomedical Science, National Tsing Hua University, Hsinchu, Taiwan, ROC.
Chan
W H
WH
Liu
H W
HW
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D003598:Cytoskeletal Proteins / Q000302:isolation & purification / Q000378:metabolism*; D003599:Cytoskeleton / Q000378:metabolism* / Q000648:ultrastructure; D004591:Electrophoresis, Polyacrylamide Gel; D007700:Kinetics; D010749:Phosphoprotein Phosphatases / Q000302:isolation & purification / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism*; D016875:tau Proteins / Q000302:isolation & purification / Q000378:metabolism
D003598:Cytoskeletal Proteins; D016875:tau Proteins; D000255:Adenosine Triphosphate; D011494:Protein Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D010749:Phosphoprotein Phosphatases