Abstract:
:Tyrosine hydroxylase (EC 1.14.16.2), the enzyme catalyzing the rate-limiting step in catecholamine biosynthesis, was localized by electron microscopy within noradrenergic neurons of the nucleus locus coeruleus of the rat brain with a specific antibody to tyrosine hydroxylase labeled by the peroxidase-antiperoxidase immunohistochemical method. Labeled cell bodies and their processes were easily distinguished from unstained neuronal elements in the neuropil. The hydroxylase was only seen in the neuronal cytoplasm. Its distribution in processes was different from that in cell soma. In longitudinal sections of axons and dendrites, the peroxides reaction product appeared as fiber-like strands aligned parallel with the plasma membrane. In cross section, the labeled structures had a diameter of 220 A and exhibited an orderly distribution within the processes. The size and distribution of the peroxidase-stained structures suggest that they are neurotubules. In the perikarya, the cytoplasm was diffusely stained; the reaction was most intense on membranes of endoplasmic reticulum and Golgi apparatus, whereas lysosomes and mitochondria did not stain. The ultrastructural localization of tyrosine hydroxylase is consistent with biochemical data suggesting that the enzyme exists in different states in cell body and processes. The ultrastructural identification of enzymes subserving synthesis of neurotransmitters in central neurons and their processes may provide a useful tool in mapping the distribution of chemically specific synapses on identifiable neurons in brain.
journal_name
Proc Natl Acad Sci U S Aauthors
Pickel VM,Joh TH,Reis DJdoi
10.1073/pnas.72.2.659subject
Has Abstractpub_date
1975-02-01 00:00:00pages
659-63issue
2eissn
0027-8424issn
1091-6490journal_volume
72pub_type
杂志文章abstract::In order to study the mutagenic effects of site-specific, covalent modifications of biologically active DNA, we need host cells that are permissive for any type of mutation that might be produced in vivo from the modified DNA. Specifically, we require a general, in vivo complementation system for the bacteriophage phi...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.75.2.774
更新日期:1978-02-01 00:00:00
abstract::The ten-eleven translocation (TET) family of methylcytosine dioxygenases initiates demethylation of DNA and is associated with tumorigenesis in many cancers; however, the mechanism is mostly unknown. Here we identify upstream activators and downstream effectors of TET1 in breast cancer using human breast cancer cells ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1305172110
更新日期:2013-06-11 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1988-01-01 00:00:00
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doi:10.1073/pnas.2536857100
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1981-10-01 00:00:00
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更新日期:2008-09-09 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1218402110
更新日期:2013-06-11 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.70.4.1122
更新日期:1973-04-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2018-06-26 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2012-04-17 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2013-01-08 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.84.6.1694
更新日期:1987-03-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2009-06-02 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2019-09-03 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2019-03-12 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2014-04-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2010-12-21 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Mitogen-stimulated scheduled DNA synthesis and DNA excision repair in human lymphocytes, as well as DNA polymerase a activity in a cell-free system, were inhibited by an electrophilic metabolite of benzo[a]pyrene. This metabolite, (+/-)-anti-(7r,8t)-dihydroxy-(9,10t)-epoxy-7,8,9,10-tetrahyd robenzo[a]pyrene (BPDE), co...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1984-09-01 00:00:00
abstract::The Paramyxoviridae family of enveloped viruses enters cells through the concerted action of two viral glycoproteins. The receptor-binding protein, hemagglutinin-neuraminidase (HN), H, or G, binds its cellular receptor and activates the fusion protein, F, which, through an extensive refolding event, brings viral and c...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1213813109
更新日期:2012-09-25 00:00:00
abstract::Several publications have attested to the ability of herpes simplex viruses to protect cells against apoptosis. We investigated the ability of the virus to protect cells in continuous cultivation from apoptosis induced by the virus itself, and by other known inducers such as exposure to the tumor necrosis factor alpha...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.95.7.3931
更新日期:1998-03-31 00:00:00
abstract::The local conformations of proteins and peptides are determined by the amino acid sequence. However, the 20 amino acids encoded by the genome allow the peptide backbone to fold into many conformations, so that even for a small peptide it becomes very difficult to predict the three-dimensional structure. By using empir...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.91.7.2649
更新日期:1994-03-29 00:00:00