Cytochrome P450 CYP2J9, a New Mouse Arachidonic Acid ω-1 Hydroxylase Predominantly Expressed in Brain
| Autor: | Robert R. Maronpot, Matthew D. Breyer, Michael P. Waalkes, Darryl C. Zeldin, Jianyong Chen, Linda S. Davis, J. Alyce Bradbury, Wei Qu, Carol E. Parker, G. Jean Harry, John R. Falck, Cheng-Chung Tsao, Robert L. Rosenberg |
|---|---|
| Rok vydání: | 2001 |
| Předmět: |
Cerebellum
DNA Complementary Molecular Sequence Data In situ hybridization Spodoptera Biology Transfection Biochemistry Cell Line Mixed Function Oxygenases law.invention CYP2J2 Mice Purkinje Cells chemistry.chemical_compound law Microsomes Complementary DNA Hydroxyeicosatetraenoic Acids medicine Animals Amino Acid Sequence RNA Messenger Molecular Biology In Situ Hybridization Messenger RNA Arachidonic Acid Base Sequence Brain Riboprobe Sequence Analysis DNA Cell Biology Molecular biology Molecular Weight medicine.anatomical_structure chemistry Recombinant DNA Arachidonic acid Calcium Channels Baculoviridae |
| Zdroj: | Journal of Biological Chemistry. 276:25467-25479 |
| ISSN: | 0021-9258 |
| DOI: | 10.1074/jbc.m100545200 |
| Popis: | A cDNA encoding a new cytochrome P450 was isolated from a mouse brain library. Sequence analysis reveals that this 1,958-base pair cDNA encodes a 57–58-kDa 502-amino acid polypeptide that is 70–91% identical to CYP2J subfamily P450s and is designated CYP2J9. Recombinant CYP2J9 was co-expressed with NADPH-cytochrome P450 oxidoreductase (CYPOR) in Sf9cells using a baculovirus system. Microsomes of CYP2J9/CYPOR-transfected cells metabolize arachidonic acid to 19-hydroxyeicosatetraenoic acid (HETE) thus CYP2J9 is enzymologically distinct from other P450s. Northern analysis reveals that CYP2J9 transcripts are present at high levels in mouse brain. Mouse brain microsomes biosynthesize 19-HETE. RNA polymerase chain reaction analysis demonstrates that CYP2J9 mRNAs are widely distributed in brain and most abundant in the cerebellum. Immunoblotting using an antibody raised against human CYP2J2 that cross-reacts with CYP2J9 detects a 56-kDa protein band that is expressed in cerebellum and other brain segments and is regulated during postnatal development. In situ hybridization of mouse brain sections with a CYP2J9-specific riboprobe and immunohistochemical staining with the anti-human CYP2J2 IgG reveals abundant CYP2J9 mRNA and protein in cerebellar Purkinje cells. Importantly, 19-HETE inhibits the activity of recombinant P/Q-type Ca2+ channels that are known to be expressed preferentially in cerebellar Purkinje cells and are involved in triggering neurotransmitter release. Based on these data, we conclude that CYP2J9 is a developmentally regulated P450 that is abundant in brain, localized to cerebellar Purkinje cells, and active in the biosynthesis of 19-HETE, an eicosanoid that inhibits activity of P/Q-type Ca2+ channels. We postulate that CYP2J9 arachidonic acid products play important functional roles in the brain. |
| Databáze: | OpenAIRE |
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