High impact information on HAT1

• Hat1p is the catalytic subunit of the histone acetyltransferase and has an intrinsic substrate specificity that modifies lysine in the recognition sequence GXGKXG [1].
• Recombinant Gcn5 shows increased histone acetyltransferase activity on nucleosomal arrays harboring phosphorylated H3 serine 10 and is consistent with peptide studies [2].
• However, in contrast to analyses using peptide substrates, we find that the histone acetyltransferase activity of the Gcn5-containing SAGA complex is not stimulated by H3 phosphorylation in the context of nucleosomal arrays [2].
• We have examined salt-soluble chromatin released by micrococcal nuclease from a 15-day-old chicken embryo erythrocyte nuclei for histone acetyltransferase (HAT) activities [3].
• Histone acetyltransferase is associated with the nuclear matrix [4].

Biological context of HAT1

• Leucine zipper motif of chicken histone acetyltransferase-1 is essential for in vivo and in vitro interactions with the p48 subunit of chicken chromatin assembly factor-1 [5].
• HAT1(-/-) cells exhibited greatly reduced diacetylation levels of Lys-5 and Lys-12, and acetylation level of Lys-5 of cytosolic and chromatin histones H4, respectively [6].
• These results indicate that HAT1 participates in recovering replication block-mediated DNA damages, probably through chromatin modulation based on acetylation of Lys-5 and Lys-12 of histone H4 [6].
• Based on the analysis of thymidine kinase activity a close correlation was established between histone acetyltransferase B and DNA replication, whereas the A2 enzyme is associated with transcriptional activity [7].
• Measurement of histone acetyltransferase and histone deacetylase activities and kinetics of histone acetylation [8].

Anatomical context of HAT1

• Nuclear matrices isolated from adult chicken immature erythrocyte and trout liver nuclei had 60-76% of the nuclear histone acetyltransferase activity [4].
• Histone acetyltransferase activity in cell extracts from chick myoblast cultures increases up to 24h of cell culture and then decreases steadily to about 30-40% of the 24h value after 6 to 7 days [9].
• Ucp3 is expressed in brown adipose tissue and skeletal muscle and controlled by a transcription factor complex including PPARalpha, MyoD and the histone acetyltransferase p300 [10].

Associations of HAT1 with chemical compounds

• HAT1(-/-) cells had mild growth defect, conferring sensitivities to methyl methanesulfonate and camptothecin that enforce replication blocks creating DNA double strand breaks [6].

Other interactions of HAT1

• Multiple enzyme forms of histone deacetylase and histone acetyltransferase exist in germinating maize embryos [11].
• Distribution of histone acetyltransferase activity among salt- and size-resolved micrococcal nuclease produced fractions was almost 5-fold greater in the 0.15 M NaCl-soluble supernatant than in the 0.15 M NaCl-insoluble pellet [12].

References