Project description:Macrophages respond to environmental cues in a plastic manner and play a crucial role in host defense, inflammation, and tissue homeostasis. Macrophage activation undergoes metabolic and transcriptomic reprogramming to adapt and tailor an appropriate response, regulating inflammation. Reactive oxygen species (ROS) have been shown to play a pivotal role in macrophage activation. Nevertheless, the detailed molecular mechanism of how initial redox signals direct macrophage activation is not fully elucidated. Here, we uncover an unconventional role for histone acetyltransferase MOF (also known as KAT8) in regulating LPS-induced macrophage activation via modulating the acetylation of peroxiredoxin 1 (PRDX1), an H2O2 scavenger. We demonstrate that PRDX1 is a novel substrate of MOF and identify the major MOF-mediated acetylation site at lysine 197. K197 acetylation of PRDX1 (K197ac PRDX1) is dynamic and reversely regulated by HDAC6 or SIRT2. We observe that this acetylation is readily diminished in the immediate response to LPS. We demonstrate that K197ac PRDX1 fine-tunes its peroxidase activity, leading to the modulation of intracellular ROS levels in early response to LPS stimulation. Moreover, K197ac PRDX1 specifically regulates ERK1/2 phosphorylation, thereby modulating glycolytic metabolism in inflammatory macrophages. Consequently, K197ac PRDX1 tunes the expression and production of the proinflammatory cytokine, IL-6. Taken together, our findings describe a novel signaling module, MOF-PRDX1-ERK, which regulates LPS-induced macrophage activation at the metabolic and transcriptional levels.
Project description:Macrophage activation undergoes signal-transduced changes in protein modifications, enabling the coordinated control of transcription and cellular metabolism. However, the role of protein acetylation in signal transduction during macrophage activation remains obscure. Here, we demonstrate that peroxiredoxin 1 (PRDX1), a key regulator of redox signaling, is a novel substrate of the MOF lysine acetyltransferase. Employing a gel based in vitro HAT assay followed by LC-MS, we mapped PRDX1 lysine acetylation sites. PRDX1 K197ac was identified as the most prominent MOF acetylation site. We show that MOF-dependent acetylation of lysine 197 of PRDX1 (PRDX1 K197ac) enhances its peroxidase activity. We find that PRDX1 K197ac is an inflammatory signal-regulated modification, which decreases in mouse macrophages stimulated with bacterial lipopolysaccharides (LPS) but not with IL-4 or IL-10. LPS-induced decrease of PRDX1 K197ac elevates cellular ROS accumulation and augments phosphorylation of ERK1/2 but not p38 or AKT phosphorylation. Concomitantly, diminished PRDX1 K197ac stimulates glycolysis, potentiates H3 serine 28 phosphorylation, and ultimately enhances the production of pro-inflammatory mediators such as IL-6. Collectively, our findings uncover a regulatory role for redox protein acetylation during inflammatory macrophage activation through modulating signal transduction and coordinating metabolic and transcriptional programs.
Project description:Reversible acetylation of mitochondrial proteins is a regulatory mechanism central to adaptive metabolic responses. Yet, how such functionally relevant protein acetylation is achieved remains unexplored. Here, we reveal an unprecedented role of the MYST family lysine acetyltransferase MOF in energy metabolism via mitochondrial protein acetylation. Loss of MOF-KANSL complex members led to mitochondrial defects including fragmentation, reduced cristae density and impaired mitochondrial electron transport chain (mtETC) complex IV (CIV) integrity in primary mouse embryonic fibroblasts. We demonstrate COX17, a CIV assembly factor, as a bona fide acetylation target of MOF. Loss of COX17 or expression of its non-acetylatable mutant phenocopied the mitochondrial defects observed upon MOF depletion. The acetylation-mimetic COX17 rescues these defects and maintains CIV activity even in the absence of MOF, suggesting an activatory role of mtETC protein acetylation. Fibroblasts from MOF syndrome patients with intellectual disability also revealed respiratory defects that could be restored by alternative oxidase, acetylation-mimetic COX17 or mitochondrially targeted MOF. Overall, our findings highlight the critical role of MOF-KANSL complex in mitochondrial physiology and provide new insights into MOF syndrome.
Project description:The multi-domain protein UHRF1 (ubiquitin-like, containing PHD and RING finger domains, 1) recruits DNMT1 for DNA methylation maintenance during DNA replication. Here, we show that MOF (Males absent On the First) is an acetyltransferase of UHRF1 to acetylate UHRF1 at Lys670 in the pre-RING linker region whereas HDAC1 is a deacetylase of UHRF1 at the same site. The MOF/HDAC1-mediated acetylation in UHRF1 is cell-cycle regulated and peaks at G1/S phase, in line with the function of UHRF1 in recruiting DNMT1 to maintain DNA methylation. In addition, UHRF1 acetylation significantly enhances its E3 ligase activity and elimination of UHRF1 acetylation at these sites attenuates UHRF1-mediated H3 ubiquitination, which in turn impairs the DNMT1 recruitment and DNA methylation. Taken together, these findings not only identify MOF as a new acetyltransferase for UHRF1 but also reveal a novel mechanism underlying the regulation of DNA methylation maintenance through MOF-mediated UHRF1 acetylation.
Project description:The multi-domain protein UHRF1 (ubiquitin-like, containing PHD and RING finger domains, 1) recruits DNMT1 for DNA methylation maintenance during DNA replication. Here, we show that MOF (Males absent On the First) is an acetyltransferase of UHRF1 to acetylate UHRF1 at Lys670 in the pre-RING linker region whereas HDAC1 is a deacetylase of UHRF1 at the same site. The MOF/HDAC1-mediated acetylation in UHRF1 is cell-cycle regulated and peaks at G1/S phase, in line with the function of UHRF1 in recruiting DNMT1 to maintain DNA methylation. In addition, UHRF1 acetylation significantly enhances its E3 ligase activity and elimination of UHRF1 acetylation at these sites attenuates UHRF1-mediated H3 ubiquitination, which in turn impairs the DNMT1 recruitment and DNA methylation. Taken together, these findings not only identify MOF as a new acetyltransferase for UHRF1 but also reveal a novel mechanism underlying the regulation of DNA methylation maintenance through MOF-mediated UHRF1 acetylation.
Project description:Histone H4 lysine 16 acetylation (H4K16Ac), governed by the histone acetyltransferase (HAT) MOF, orchestrates critical functions in gene expression regulation and chromatin interaction. In this study, we show that conditional genetic deletion of Mof but not Kansl1, the essential component of the NSL complex, causes severe defects during murine skin development. Single-cell and bulk RNA-seq, in combination with MOF ChIP-seq, reveal that numerous MOF targeted and downregulated genes are highly enriched in mitochondria and cilia. Genetic deletion of Uqcrq, an essential subunit for electron transport chain Complex III, recapitulates the defects observed in MOF cKO. Single-cell ATAC-seq reveals that MOF targeted genes are controlled prominently through promoter interactions.
Project description:Histone H4 lysine 16 acetylation (H4K16Ac), governed by the histone acetyltransferase (HAT) MOF, orchestrates critical functions in gene expression regulation and chromatin interaction. In this study, we show that conditional genetic deletion of Mof but not Kansl1, the essential component of the NSL complex, causes severe defects during murine skin development. Single-cell and bulk RNA-seq, in combination with MOF ChIP-seq, reveal that numerous MOF targeted and downregulated genes are highly enriched in mitochondria and cilia. Genetic deletion of Uqcrq, an essential subunit for electron transport chain Complex III, recapitulates the defects observed in MOF cKO. Single-cell ATAC-seq reveals that MOF targeted genes are controlled prominently through promoter interactions.
Project description:Histone H4 lysine 16 acetylation (H4K16Ac), governed by the histone acetyltransferase (HAT) MOF, orchestrates critical functions in gene expression regulation and chromatin interaction. In this study, we show that conditional genetic deletion of Mof but not Kansl1, the essential component of the NSL complex, causes severe defects during murine skin development. Single-cell and bulk RNA-seq, in combination with MOF ChIP-seq, reveal that numerous MOF targeted and downregulated genes are highly enriched in mitochondria and cilia. Genetic deletion of Uqcrq, an essential subunit for electron transport chain Complex III, recapitulates the defects observed in MOF cKO. Single-cell ATAC-seq reveals that MOF targeted genes are controlled prominently through promoter interactions.
Project description:Histone H4 lysine 16 acetylation (H4K16Ac), governed by the histone acetyltransferase (HAT) MOF, orchestrates critical functions in gene expression regulation and chromatin interaction. In this study, we show that conditional genetic deletion of Mof but not Kansl1, the essential component of the NSL complex, causes severe defects during murine skin development. Single-cell and bulk RNA-seq, in combination with MOF ChIP-seq, reveal that numerous MOF targeted and downregulated genes are highly enriched in mitochondria and cilia. Genetic deletion of Uqcrq, an essential subunit for electron transport chain Complex III, recapitulates the defects observed in MOF cKO. Single-cell ATAC-seq reveals that MOF targeted genes are controlled prominently through promoter interactions.
Project description:Protein post-translational modifications transmit signals in part by creating binding sites for effector molecules. This is especially true in epigenetic pathways where histone tails are heavily modified, resulting in the recruitment of molecules that can affect transcription. One such molecule, plant homeodomain finger protein 20 (PHF20), uses a Tudor domain to read dimethyl-lysine residues and is a known component of the MOF histone acetyltransferase protein complex, suggesting it plays a role in the crosstalk between lysine methylation and histone acetylation. We sought to investigate the biological role of PHF20 by generating a knockout mouse. Without PHF20, mice die shortly after birth and display a wide variety of phenotypes within the skeletal and hematopoietic systems. Mechanistically, PHF20 is not required for maintaining the global H4K16 acetylation levels, but instead works downstream in transcriptional regulation of MOF target genes. ChIP sequencing of H4K16ace ChIP DNA from PHF20 knockout and wild type cells using Illumina Solexa Genome Analyzer II single end sequencing protocol.