Akiko Okumura

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L-carnosine is a bioactive dipeptide (beta-alanyl-L-histidine) present in mammalian tissues, including the central nervous system, and has potential neuroprotective and neurotransmitter functions. In mammals, two types of L-carnosine-hydrolyzing enzymes (CN1 and CN2) have been cloned thus far, and they have been classified as metallopeptidases of the M20(More)
Carnosine is a naturally occurring dipeptide (beta-alanyl-l-histidine) present in mammalian tissues such as the brain and skeletal muscles. Carnosine is not only a radical scavenger but also a possible neurotransmitter-like molecule that regulates neuronal functions such as hypothalamic control of the autonomic nervous system. CN2 (CNDP2) is a cytosolic(More)
Fyn is a Src-family tyrosine kinase involved in neuronal development, transmission, and plasticity in mammalian central nervous system. We have previously reported that Fyn binds to a cytoskeletal protein, beta-adducin, in a phosphorylation-dependent manner. In the present report, we show that Fyn phosphorylates beta-adducin at tyrosine 489 located in its(More)
Syntrophins are components of the dystrophin-glycoprotein complex of the plasma membrane in muscular and neuronal cells, and recruit signaling proteins such as neuronal nitric oxide synthase via their multiple protein-protein interaction motifs. In this study, we found that alpha1-syntrophin binds to various subtypes of guanine nucleotide-binding protein(More)
Reactive plasmacytosis is a transient expansion of plasma cell progenitors and precursors. This rare condition has been reported to occur mainly in infections and tumors. We describe a case of acute hepatitis A presenting with marked peripheral blood plasmacytosis. Plasma cells made up 27.5% of the mononuclear cells and had the immunophenotype(More)
beta-Adducin is a cytoskeletal protein that interacts with the actin filaments to suppress actin polymerization and facilitate actin-spectrin binding. We have previously shown that beta-adducin is phosphorylated by Fyn at tyrosine489 in the rat brain and bound to its Src-homology 2 domain. In the present study, we examined the immunohistochemical(More)
In the mammalian brain, nitric oxide (NO) has been implicated in neuronal signal transmissions. NO stimulates guanylate cyclase to increase intracellular cGMP, which in turn activates cGMP-dependent protein kinases (PKG), but the targets of PKG in the brain have not fully been understood. In this study, we examined cGMP-dependent phosphorylation of proteins(More)
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