Developmental expression in the mouse nervous system of the p493F12 SAP kinase.
Mitogen-activated protein (MAP) kinases are proline-directed, serine/threonine kinases that respond to a variety of extracellular signals. A subgroup of these kinases, stress-activated protein (SAP) kinases, phosphorylate c-jun in response to cellular stress. Using monoclonal antibody (MAb) 3F12, we have cloned and partially characterized p493F12 kinase, a mouse homologue of the rat SAP beta kinase and described its expression in the adult and developing mouse. Unlike previously reported MAP and SAP kinases, it is primarily expressed as a 2.7 kb transcript in neurons in the nervous system of the adult mouse. A 2.4 kb transcript is also expressed in the testis. Immunocytochemically, MAb 3F12 decorates a loop-like structure encircling the nucleus in the cytoplasm of neurons in the adult brain, and distinct perinuclear dots in the embryos. In situ hybridization first reveals expression in post-mitotic neurons, on embryonic day 11. The mRNA is also expressed in the Neuro-2A neuroblastoma cell line and is not upregulated in response to differentiating agents. The neuronal specificity of this kinase suggests the presence of a signal transduction cascade unique to neurons. As the amino acid sequence is highly conserved in the human and mouse, the latter may serve as a model for regulation and expression of this kinase.
Martin
J H
JH
Department of Pathology and Neurology, University of Southern California School of Medicine, Los Angeles 90033, USA.
Mohit
A A
AA
Miller
C A
CA
D000375:Aging / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000196:embryology / Q000201:enzymology* / Q000254:growth & development; D003001:Cloning, Molecular; D005314:Embryonic and Fetal Development; D005260:Female; D018507:Gene Expression Regulation, Developmental; D005865:Gestational Age; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D048057:Mitogen-Activated Protein Kinase 10; D020928:Mitogen-Activated Protein Kinases; D008969:Molecular Sequence Data; D009474:Neurons / Q000166:cytology / Q000201:enzymology*; D009928:Organ Specificity; D011247:Pregnancy; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis*; D011505:Protein-Tyrosine Kinases / Q000096:biosynthesis*; D051381:Rats; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D013737:Testis / Q000166:cytology / Q000201:enzymology*
D048057:Mitogen-Activated Protein Kinase 10; D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D020928:Mitogen-Activated Protein Kinases