The NuA4 histone acetyltransferase complex is a
protein complex that has
histoneacetylase activity on
chromatin, as well as
ATPase,
DNAhelicase and
structuralDNA binding activities. The complex is thought to be involved in double-strand
DNA break repair. Subunits of the human complex include HTATIP/TIP60,
TRRAP,
RUVBL1,
RUVBL2,
beta-actin and BAF53/ACTL6A. In
yeast, the complex has 13 subunits, including the catalytic subunit Esa1 (homologous to human Tip60).[1]
Post-translational
acetylation of the
histone H4 N-terminal tail in
chromatin has been associated with several
nuclear processes including
transcription. Purification and characterization of a native multi-subunit complex (NuA4) from yeast that acetylates nucleosomal histone H4 have been reported. NuA4 has an apparent molecular mass of 1.3 MDa. All four conserved
lysines of histone H4 can be acetylated by NuA4. The catalytic subunit of the complex has been identified as the product of ESA1, an essential gene required for cell cycle progression in yeast. Antibodies against Esa1p specifically
immunoprecipitate NuA4 activity whereas the complex purified from a temperature-sensitive esa1 mutant loses its acetyltransferase activity at the restrictive temperature. Additionally, another subunit of the complex has been identified as the product of TRA1, an ATM-related essential gene homologous to human TRRAP, an essential cofactor for c-Myc- and E2F-mediated oncogenic transformation. Finally, the ability of NuA4 to stimulate GAL4–VP16-driven transcription from chromatin templates in vitro is also lost in the temperature-sensitive esa1 mutant. The function of the essential Esa1
protein as the HAT subunit of NuA4 and the presence of Tra1p, a putative [[transcription]] activator-interacting subunit, supports an essential link between nuclear H4 acetylation, transcriptional regulation and cell cycle control.[2][3]
The NuA4 histone acetyltransferase complex is a
protein complex that has
histoneacetylase activity on
chromatin, as well as
ATPase,
DNAhelicase and
structuralDNA binding activities. The complex is thought to be involved in double-strand
DNA break repair. Subunits of the human complex include HTATIP/TIP60,
TRRAP,
RUVBL1,
RUVBL2,
beta-actin and BAF53/ACTL6A. In
yeast, the complex has 13 subunits, including the catalytic subunit Esa1 (homologous to human Tip60).[1]
Post-translational
acetylation of the
histone H4 N-terminal tail in
chromatin has been associated with several
nuclear processes including
transcription. Purification and characterization of a native multi-subunit complex (NuA4) from yeast that acetylates nucleosomal histone H4 have been reported. NuA4 has an apparent molecular mass of 1.3 MDa. All four conserved
lysines of histone H4 can be acetylated by NuA4. The catalytic subunit of the complex has been identified as the product of ESA1, an essential gene required for cell cycle progression in yeast. Antibodies against Esa1p specifically
immunoprecipitate NuA4 activity whereas the complex purified from a temperature-sensitive esa1 mutant loses its acetyltransferase activity at the restrictive temperature. Additionally, another subunit of the complex has been identified as the product of TRA1, an ATM-related essential gene homologous to human TRRAP, an essential cofactor for c-Myc- and E2F-mediated oncogenic transformation. Finally, the ability of NuA4 to stimulate GAL4–VP16-driven transcription from chromatin templates in vitro is also lost in the temperature-sensitive esa1 mutant. The function of the essential Esa1
protein as the HAT subunit of NuA4 and the presence of Tra1p, a putative [[transcription]] activator-interacting subunit, supports an essential link between nuclear H4 acetylation, transcriptional regulation and cell cycle control.[2][3]