Protein phosphorylation and taurine biosynthesis in vivo and in vitro.
Taurine is known to be involved in many important physiological functions. Here we report that both in vivo and in vitro the taurine-synthesizing enzyme in the brain, namely cysteine sulfinic acid decarboxylase (CSAD), is activated when phosphorylated and inhibited when dephosphorylated. Furthermore, protein kinase C and protein phosphatase 2C have been identified as the enzymes responsible for phosphorylation and dephosphorylation of CSAD, respectively. In addition, the effect of neuronal depolarization on CSAD activity and 32P incorporation into CSAD in neuronal cultures is also included. A model to link neuronal excitation and CSAD activation by a Ca2+-dependent protein kinase is proposed.
Tang
X W
XW
Department of Physiology and Cell Biology, University of Kansas, Lawrence, Kansas 66045-2106, USA.
Hsu
C C
CC
Schloss
J V
JV
Faiman
M D
MD
Wu
E
E
Yang
C Y
CY
Wu
J Y
JY
D000818:Animals; D002262:Carboxy-Lyases / Q000378:metabolism*; D002478:Cells, Cultured; D004789:Enzyme Activation; D005968:Glutamate Decarboxylase / Q000378:metabolism; D008956:Models, Chemical; D010749:Phosphoprotein Phosphatases / Q000378:metabolism; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism; D011494:Protein Kinases / Q000378:metabolism; D054648:Protein Phosphatase 2; D000071636:Protein Phosphatase 2C; D011506:Proteins / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D013552:Swine; D013574:Synaptosomes / Q000378:metabolism; D013654:Taurine / Q000096:biosynthesis*; D017871:Calcium-Calmodulin-Dependent Protein Kinases
D002262:Carboxy-Lyases; D005968:Glutamate Decarboxylase; D010749:Phosphoprotein Phosphatases; D011493:Protein Kinase C; D011494:Protein Kinases; D054648:Protein Phosphatase 2; D000071636:Protein Phosphatase 2C; D011506:Proteins; D029701:Saccharomyces cerevisiae Proteins; D013654:Taurine; D017871:Calcium-Calmodulin-Dependent Protein Kinases; C087358:PTC1 protein, S cerevisiae; C019972:sulfoalanine decarboxylase