Cdk5 and the mystery of synaptic vesicle endocytosis.
Regulation of endocytosis by protein phosphorylation and dephosphorylation is critical to synaptic vesicle recycling. Two groups have now identified the neuronal kinase Cdk5 (cyclin-dependent kinase 5) as an important regulator of this process. Robinson and coworkers recently demonstrated that Cdk5 is necessary for synaptic vesicle endocytosis (SVE) (Tan et al., 2003), whereas a new report in this issue claims that Cdk5 negatively regulates SVE (Tomizawa et al., 2003). Careful examination of the data reveals a model that helps resolve the apparently contradictory nature of these reports.
Nguyen
Chan
C
Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX 75390-9070, USA.
Bibb
James A
JA
D000818:Animals; D051360:Cyclin-Dependent Kinase 5; D018844:Cyclin-Dependent Kinases / Q000378:metabolism*; D034281:Dynamins / Q000378:metabolism; D004705:Endocytosis / Q000502:physiology*; D025461:Feedback, Physiological / Q000502:physiology; D006801:Humans; D008954:Models, Biological; D010766:Phosphorylation; D017729:Presynaptic Terminals / Q000201:enzymology* / Q000648:ultrastructure; D013572:Synaptic Vesicles / Q000201:enzymology* / Q000648:ultrastructure
D051360:Cyclin-Dependent Kinase 5; C495905:CDK5 protein, human; D018844:Cyclin-Dependent Kinases; D034281:Dynamins