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Attenuated neurotoxicity of the transactivation-defective HIV-1 Tat protein in hippocampal cell cultures.

ABSTRACT: This study reports that the cysteine 22-->glycine 22 substitution in the HIV-1 Tat 1-86 B significantly attenuates its neurotoxicity. Consistent with previous studies, direct interactions of rat hippocampal cells with Tat 1-86 B were shown to cause dose-dependent and time-dependent neurotoxicity associated with activation of caspases from the mitochondrial apoptotic pathway. Despite the similar binding/uptake properties, Cys22 Tat 1-86 B failed to induce significant neurotoxicity and activation of caspases 9 and 3/7 in hippocampal primary cultures. Results of the study underscore the important role of cysteine-rich domain in mechanism of Tat-mediated neurotoxicity.

SUBMITTER: Aksenov MY

PROVIDER: S-EPMC2770879 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Attenuated neurotoxicity of the transactivation-defective HIV-1 Tat protein in hippocampal cell cultures.

Aksenov Michael Y MY Aksenova Marina V MV Mactutus Charles F CF Booze Rosemarie M RM

Experimental neurology 20090715 2

This study reports that the cysteine 22-->glycine 22 substitution in the HIV-1 Tat 1-86 B significantly attenuates its neurotoxicity. Consistent with previous studies, direct interactions of rat hippocampal cells with Tat 1-86 B were shown to cause dose-dependent and time-dependent neurotoxicity associated with activation of caspases from the mitochondrial apoptotic pathway. Despite the similar binding/uptake properties, Cys22 Tat 1-86 B failed to induce significant neurotoxicity and activation ...[more]

PMID: 19615365

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