Article

HDAC7, a thymus-specific class II histone deacetylase, regulates Nur77 transcription and TCR-mediated apoptosis.

Gladstone Institute of Virology and Immunology, University of California, San Francisco, San Francisco 94141, USA.
Immunity (impact factor: 21.64). 06/2003; 18(5):687-98. pp.687-98
Source: PubMed

ABSTRACT We report that HDAC7, a class II histone deacetylase, is highly expressed in CD4(+)CD8(+) double-positive thymocytes. HDAC7 inhibits the expression of Nur77, an orphan receptor involved in apoptosis and negative selection, via the transcription factor MEF2D. HDAC7 is exported from the nucleus during T cell receptor activation, leading to Nur77 expression. A triple HDAC7 mutant (S155A, S318A, S448A) is not exported from the nucleus in response to TCR activation and suppresses TCR-mediated apoptosis. Conversely, a fusion of HDAC7 to the transcriptional activator VP16 activates Nur77 expression. Inhibition of HDAC7 expression by RNA interference causes increased apoptosis in response to TCR activation. These observations define HDAC7 as a regulator of Nur77 and apoptosis in developing thymocytes.

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Keywords

apoptosis
 
class II histone deacetylase
 
HDAC7 expression
 
Inhibition
 
negative selection
 
Nur77 expression
 
observations define HDAC7
 
orphan receptor
 
regulator
 
RNA interference causes
 
suppresses TCR-mediated apoptosis
 
T cell receptor activation
 
TCR activation
 
thymocytes
 
transcription factor MEF2D
 
transcriptional activator VP16 activates Nur77 expression
 
triple HDAC7 mutant