Microtubule affinity-regulating kinase 1 (MARK1) is activated by electroconvulsive shock in the rat hippocampus.
Electroconvulsive shock (ECS) induces phosphorylation and dephosphorylation of many signaling molecules in the rat brain. While studying phosphorylated proteins in the rat brain after ECS, we observed a 100-kDa protein that cross-reacted with anti-phospho-p70 S6 kinase antibody, which was subsequently purified and identified as microtubule affinity-regulating kinase 1 (MARK1). Purified MARK1 was phosphorylated at the Ser and Thr residues. MARK1 activation and subsequent Tau phosphorylation in the hippocampus after ECS was confirmed by an in-gel kinase assay using tau protein as a substrate. MARK1 was maximally activated between 2 and 5 min after ECS, and Tau phosphorylation at Ser262 was also increased at 2 min and lasted to 1 h after ECS. Taken together, we concluded that ECS activated MARK1 and subsequently phosphorylated Tau at Ser262. Both MARK1 activity and Tau phosphorylation were increased in the rat hippocampus after chronic ECS where axonal remodeling was apparent. In order to investigate the physiologic stimuli which are involved in the activation of MARK1, SH-SY 5Y cells were treated with brain-derived neurotrophic factor or 60 mm KCl. Both stimuli were capable of inducing MARK activation.
Jeon
Songhee
S
Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon, Korea.
Kim
Yong-Sik
YS
Park
Joobae
J
Bae
Chang-Dae
CD
D000595:Amino Acid Sequence; D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000494:pharmacology; D045744:Cell Line, Tumor; D004591:Electrophoresis, Polyacrylamide Gel; D004597:Electroshock; D006624:Hippocampus / Q000502:physiology*; D015151:Immunoblotting; D008297:Male; D008969:Molecular Sequence Data; D009473:Neuronal Plasticity / Q000187:drug effects; D010766:Phosphorylation; D011189:Potassium Chloride / Q000494:pharmacology; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D016875:tau Proteins / Q000378:metabolism
D019208:Brain-Derived Neurotrophic Factor; D016875:tau Proteins; D011189:Potassium Chloride; C484552:Mark1 protein, rat; D017346:Protein Serine-Threonine Kinases