Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
47
pubmed:dateCreated
2008-11-21
pubmed:abstractText
In countries infected with HIV clade B, some patients develop a rapidly progressive dementia that if untreated results in death. In regions of the world infected with HIV clade C, only milder forms of cognitive impairment have been recognized. HIV-infected macrophages are the principal mediators of dementia. HIV clade C, however, efficiently infects macrophages and HIV-infected macrophages are found in the brains of clade C-infected patients. HIV-infected macrophages release Tat protein, which may act directly on neurons to cause toxicity. We found that Tat released from Tat-expressing cells was at least 1000-fold more toxic than recombinant Tat protein. We determined whether Tat could interact with NMDA receptors and whether these interactions are clade dependent. It is demonstrated that Tat binds directly to the NMDA receptor leading to excitotoxicity. The Cys 30-Cys 31 motif in Tat is critical for exciting the NMDA receptor and the Cys31Ser mutation found in clade C Tat has a significantly attenuated neurotoxic response. Through molecular modeling and site-directed mutagenesis, we predict that Cys 31 disrupts the disulfide bond between Cys 744 and Cys 798 on the NR1 subunit of the NMDA receptor by directly interacting with Cys 744 leading to a free thiol group on Cys 798 and subsequent persistent activation of the NMDA receptor.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1529-2401
pubmed:author
pubmed:issnType
Electronic
pubmed:day
19
pubmed:volume
28
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
12190-8
pubmed:meshHeading
pubmed-meshheading:19020013-Amino Acid Motifs, pubmed-meshheading:19020013-Animals, pubmed-meshheading:19020013-Antibodies, pubmed-meshheading:19020013-Cells, Cultured, pubmed-meshheading:19020013-Cysteine, pubmed-meshheading:19020013-Dizocilpine Maleate, pubmed-meshheading:19020013-Dose-Response Relationship, Drug, pubmed-meshheading:19020013-Embryo, Mammalian, pubmed-meshheading:19020013-Excitatory Amino Acid Antagonists, pubmed-meshheading:19020013-Gene Expression Regulation, pubmed-meshheading:19020013-Hippocampus, pubmed-meshheading:19020013-Humans, pubmed-meshheading:19020013-Immunoprecipitation, pubmed-meshheading:19020013-Models, Molecular, pubmed-meshheading:19020013-Mutagenesis, Site-Directed, pubmed-meshheading:19020013-Neurons, pubmed-meshheading:19020013-Nitric Oxide Donors, pubmed-meshheading:19020013-Protein Binding, pubmed-meshheading:19020013-Rats, pubmed-meshheading:19020013-Receptors, N-Methyl-D-Aspartate, pubmed-meshheading:19020013-S-Nitrosoglutathione, pubmed-meshheading:19020013-Serine, pubmed-meshheading:19020013-Transfection, pubmed-meshheading:19020013-Valine, pubmed-meshheading:19020013-tat Gene Products, Human Immunodeficiency Virus
pubmed:year
2008
pubmed:articleTitle
NMDA receptor activation by HIV-Tat protein is clade dependent.
pubmed:affiliation
Department of Neurology, Johns Hopkins University, Baltimore, Maryland 21287, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural, Research Support, N.I.H., Intramural