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Histone acetyl transferase 1 is essential for mammalian development, genome stability, and the processing of newly synthesized histones H3 and H4.

Nagarajan P, Ge Z, Sirbu B, Doughty C, Agudelo Garcia PA, Schlederer M, Annunziato AT, Cortez D, Kenner L, Parthun MR - PLoS Genet. (2013)

Bottom Line: Murine Hat1 is essential for viability, as homozygous deletion of Hat1 results in neonatal lethality.The neonatal lethality is due to severe defects in lung development that result in less aeration and respiratory distress.Many of the Hat1(-/-) neonates also display significant craniofacial defects with abnormalities in the bones of the skull and jaw.

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, OH, USA.

ABSTRACT
Histone acetyltransferase 1 is an evolutionarily conserved type B histone acetyltransferase that is thought to be responsible for the diacetylation of newly synthesized histone H4 on lysines 5 and 12 during chromatin assembly. To understand the function of this enzyme in a complex organism, we have constructed a conditional mouse knockout model of Hat1. Murine Hat1 is essential for viability, as homozygous deletion of Hat1 results in neonatal lethality. The lungs of embryos and pups genetically deficient in Hat1 were much less mature upon histological evaluation. The neonatal lethality is due to severe defects in lung development that result in less aeration and respiratory distress. Many of the Hat1(-/-) neonates also display significant craniofacial defects with abnormalities in the bones of the skull and jaw. Hat1(-/-) mouse embryonic fibroblasts (MEFs) are defective in cell proliferation and are sensitive to DNA damaging agents. In addition, the Hat1(-/-) MEFs display a marked increase in genome instability. Analysis of histone dynamics at sites of replication-coupled chromatin assembly demonstrates that Hat1 is not only responsible for the acetylation of newly synthesized histone H4 but is also required to maintain the acetylation of histone H3 on lysines 9, 18, and 27 during replication-coupled chromatin assembly.

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Related in: MedlinePlus

Hat1−/− MEFs display cell proliferation and DNA damage repair defects.A) Hat1+/+, Hat1+/− and Hat1−/− primary MEFs were genotyped by PCR as described in the legend to Figure 1. Whole cell extracts from the indicated MEFs were analyzed by Western blots probed with the indicated antibodies. B) Equal numbers of primary MEFs of the indicated genotype were seeded at time zero. Cell numbers were counted at the indicated time points. C) Primary Hat1+/+ and Hat1−/− MEFs were stained with propidium iodide and analyzed by FACS. Fraction of cells in each phase of the cell cycle is indicated. D) Immortalized Hat1+/+ and Hat1−/− MEFs were grown under the indicated conditions. Plates were photographed after crystal violet staining.
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pgen-1003518-g004: Hat1−/− MEFs display cell proliferation and DNA damage repair defects.A) Hat1+/+, Hat1+/− and Hat1−/− primary MEFs were genotyped by PCR as described in the legend to Figure 1. Whole cell extracts from the indicated MEFs were analyzed by Western blots probed with the indicated antibodies. B) Equal numbers of primary MEFs of the indicated genotype were seeded at time zero. Cell numbers were counted at the indicated time points. C) Primary Hat1+/+ and Hat1−/− MEFs were stained with propidium iodide and analyzed by FACS. Fraction of cells in each phase of the cell cycle is indicated. D) Immortalized Hat1+/+ and Hat1−/− MEFs were grown under the indicated conditions. Plates were photographed after crystal violet staining.

Mentions: The fact that Hat1−/− offspring survive to at least late embryogenesis facilitated the generation of Hat1−/− embryonic fibroblast cell lines to address specific questions about the function of Hat1 in mammalian cells. Mouse embryonic fibroblasts (MEFs) were generated from Hat1+/+, Hat1+/− and Hat1−/− embryos (Figure 4A). Western blot analysis using α-Hat1 antibodies confirmed that the MEFs isolated from the Hat1−/− embryos were completely devoid of Hat1 protein (Figure 4A). In addition, heterozygous MEFs (isolated from Hat1+/Hat1− embryos) showed an ∼2-fold decrease in Hat1 protein levels.


Histone acetyl transferase 1 is essential for mammalian development, genome stability, and the processing of newly synthesized histones H3 and H4.

Nagarajan P, Ge Z, Sirbu B, Doughty C, Agudelo Garcia PA, Schlederer M, Annunziato AT, Cortez D, Kenner L, Parthun MR - PLoS Genet. (2013)

Hat1−/− MEFs display cell proliferation and DNA damage repair defects.A) Hat1+/+, Hat1+/− and Hat1−/− primary MEFs were genotyped by PCR as described in the legend to Figure 1. Whole cell extracts from the indicated MEFs were analyzed by Western blots probed with the indicated antibodies. B) Equal numbers of primary MEFs of the indicated genotype were seeded at time zero. Cell numbers were counted at the indicated time points. C) Primary Hat1+/+ and Hat1−/− MEFs were stained with propidium iodide and analyzed by FACS. Fraction of cells in each phase of the cell cycle is indicated. D) Immortalized Hat1+/+ and Hat1−/− MEFs were grown under the indicated conditions. Plates were photographed after crystal violet staining.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3675013&req=5

pgen-1003518-g004: Hat1−/− MEFs display cell proliferation and DNA damage repair defects.A) Hat1+/+, Hat1+/− and Hat1−/− primary MEFs were genotyped by PCR as described in the legend to Figure 1. Whole cell extracts from the indicated MEFs were analyzed by Western blots probed with the indicated antibodies. B) Equal numbers of primary MEFs of the indicated genotype were seeded at time zero. Cell numbers were counted at the indicated time points. C) Primary Hat1+/+ and Hat1−/− MEFs were stained with propidium iodide and analyzed by FACS. Fraction of cells in each phase of the cell cycle is indicated. D) Immortalized Hat1+/+ and Hat1−/− MEFs were grown under the indicated conditions. Plates were photographed after crystal violet staining.
Mentions: The fact that Hat1−/− offspring survive to at least late embryogenesis facilitated the generation of Hat1−/− embryonic fibroblast cell lines to address specific questions about the function of Hat1 in mammalian cells. Mouse embryonic fibroblasts (MEFs) were generated from Hat1+/+, Hat1+/− and Hat1−/− embryos (Figure 4A). Western blot analysis using α-Hat1 antibodies confirmed that the MEFs isolated from the Hat1−/− embryos were completely devoid of Hat1 protein (Figure 4A). In addition, heterozygous MEFs (isolated from Hat1+/Hat1− embryos) showed an ∼2-fold decrease in Hat1 protein levels.

Bottom Line: Murine Hat1 is essential for viability, as homozygous deletion of Hat1 results in neonatal lethality.The neonatal lethality is due to severe defects in lung development that result in less aeration and respiratory distress.Many of the Hat1(-/-) neonates also display significant craniofacial defects with abnormalities in the bones of the skull and jaw.

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, OH, USA.

ABSTRACT
Histone acetyltransferase 1 is an evolutionarily conserved type B histone acetyltransferase that is thought to be responsible for the diacetylation of newly synthesized histone H4 on lysines 5 and 12 during chromatin assembly. To understand the function of this enzyme in a complex organism, we have constructed a conditional mouse knockout model of Hat1. Murine Hat1 is essential for viability, as homozygous deletion of Hat1 results in neonatal lethality. The lungs of embryos and pups genetically deficient in Hat1 were much less mature upon histological evaluation. The neonatal lethality is due to severe defects in lung development that result in less aeration and respiratory distress. Many of the Hat1(-/-) neonates also display significant craniofacial defects with abnormalities in the bones of the skull and jaw. Hat1(-/-) mouse embryonic fibroblasts (MEFs) are defective in cell proliferation and are sensitive to DNA damaging agents. In addition, the Hat1(-/-) MEFs display a marked increase in genome instability. Analysis of histone dynamics at sites of replication-coupled chromatin assembly demonstrates that Hat1 is not only responsible for the acetylation of newly synthesized histone H4 but is also required to maintain the acetylation of histone H3 on lysines 9, 18, and 27 during replication-coupled chromatin assembly.

Show MeSH
Related in: MedlinePlus