bims-meprid 2023-06-11 papers

Issue of 2023‒06‒11
four papers selected by
Alessandro Carrer
Veneto Institute of Molecular Medicine

Nat Commun. 2023 Jun 05. 14(1): 3265

ACL and HAT1 form a nuclear module to acetylate histone H4K5 and promote cell proliferation.

Qiutao Xu, Yaping Yue, Biao Liu, Zhengting Chen, Xuan Ma, Jing Wang, Yu Zhao, Dao-Xiu Zhou.

Acetyl-CoA utilized by histone acetyltransferases (HAT) for chromatin modification is mainly generated by ATP-citrate lyase (ACL) from glucose sources. How ACL locally establishes acetyl-CoA production for histone acetylation remains unclear. Here we show that ACL subunit A2 (ACLA2) is present in nuclear condensates, is required for nuclear acetyl-CoA accumulation and acetylation of specific histone lysine residues, and interacts with Histone AcetylTransferase1 (HAT1) in rice. The rice HAT1 acetylates histone H4K5 and H4K16 and its activity on H4K5 requires ACLA2. Mutations of rice ACLA2 and HAT1 (HAG704) genes impair cell division in developing endosperm, result in decreases of H4K5 acetylation at largely the same genomic regions, affect the expression of similar sets of genes, and lead to cell cycle S phase stagnation in the endosperm dividing nuclei. These results indicate that the HAT1-ACLA2 module selectively promotes histone lysine acetylation in specific genomic regions and unravel a mechanism of local acetyl-CoA production which couples energy metabolism with cell division.

DOI: https://doi.org/10.1038/s41467-023-39101-4

Adv Sci (Weinh). 2023 Jun 06. e2301094

MSL1 Promotes Liver Regeneration by Driving Phase Separation of STAT3 and Histone H4 and Enhancing Their Acetylation.

Yucheng He, Shichao Wang, Shenghui Liu, Dan Qin, Zhangmei Liu, Liqiang Wang, Xiangmei Chen, Lisheng Zhang.

Male-specific lethal 1 (MSL1) is critical for the formation of MSL histone acetyltransferase complex which acetylates histone H4 Lys16 (H4K16ac) to activate gene expression. However, the role of MSL1 in liver regeneration is poorly understood. Here, this work identifies MSL1 as a key regulator of STAT3 and histone H4 (H4) in hepatocytes. MSL1 forms condensates with STAT3 or H4 through liquid-liquid phase separation to enrich acetyl-coenzyme A (Ac-CoA), and Ac-CoA in turn enhances MSL1 condensate formation, synergetically promoting the acetylation of STAT3 K685 and H4K16, thus stimulating liver regeneration after partial hepatectomy (PH). Additionally, increasing Ac-CoA level can enhance STAT3 and H4 acetylation, thus promoting liver regeneration in aged mice. The results demonstrate that MSL1 condensate-mediated STAT3 and H4 acetylation play an important role in liver regeneration. Thus, promoting the phase separation of MSL1 and increasing Ac-CoA level may be a novel therapeutic strategy for acute liver diseases and transplantation.

Keywords: MSL1; STAT3; acetyl coenzyme A; histone H4; liquid-liquid phase separation; liver regeneration

DOI: https://doi.org/10.1002/advs.202301094

Nat Microbiol. 2023 Jun 05.

Sexual differentiation in human malaria parasites is regulated by competition between phospholipid metabolism and histone methylation.

Chantal T Harris, Xinran Tong, Riward Campelo, Inês M Marreiros, Leen N Vanheer, Navid Nahiyaan, Vanessa A Zuzarte-Luís, Kirk W Deitsch, Maria M Mota, Kyu Y Rhee, Björn F C Kafsack.

For Plasmodium falciparum, the most widespread and virulent malaria parasite that infects humans, persistence depends on continuous asexual replication in red blood cells, while transmission to their mosquito vector requires asexual blood-stage parasites to differentiate into non-replicating gametocytes. This decision is controlled by stochastic derepression of a heterochromatin-silenced locus encoding AP2-G, the master transcription factor of sexual differentiation. The frequency of ap2-g derepression was shown to be responsive to extracellular phospholipid precursors but the mechanism linking these metabolites to epigenetic regulation of ap2-g was unknown. Through a combination of molecular genetics, metabolomics and chromatin profiling, we show that this response is mediated by metabolic competition for the methyl donor S-adenosylmethionine between histone methyltransferases and phosphoethanolamine methyltransferase, a critical enzyme in the parasite's pathway for de novo phosphatidylcholine synthesis. When phosphatidylcholine precursors are scarce, increased consumption of SAM for de novo phosphatidylcholine synthesis impairs maintenance of the histone methylation responsible for silencing ap2-g, increasing the frequency of derepression and sexual differentiation. This provides a key mechanistic link that explains how LysoPC and choline availability can alter the chromatin status of the ap2-g locus controlling sexual differentiation.

DOI: https://doi.org/10.1038/s41564-023-01396-w

bioRxiv. 2023 May 22. pii: 2023.05.22.541833. [Epub ahead of print]

Mitochondrial citrate carrier SLC25A1 is a dosage-dependent regulator of metabolic reprogramming and morphogenesis in the developing heart.

Chiemela Ohanele, Jessica N Peoples, Anja Karlstaedt, Joshua T Geiger, Ashley D Gayle, Nasab Ghazal, Fateemaa Sohani, Milton E Brown, Michael E Davis, George A Porter, Victor Faundez, Jennifer Q Kwong.

The developing mammalian heart undergoes an important metabolic shift from glycolysis toward mitochondrial oxidation, such that oxidative phosphorylation defects may present with cardiac abnormalities. Here, we describe a new mechanistic link between mitochondria and cardiac morphogenesis, uncovered by studying mice with systemic loss of the mitochondrial citrate carrier SLC25A1. Slc25a1 null embryos displayed impaired growth, cardiac malformations, and aberrant mitochondrial function. Importantly, Slc25a1 haploinsufficient embryos, which are overtly indistinguishable from wild type, exhibited an increased frequency of these defects, suggesting Slc25a1 dose-dependent effects. Supporting clinical relevance, we found a near-significant association between ultrarare human pathogenic SLC25A1 variants and pediatric congenital heart disease. Mechanistically, SLC25A1 may link mitochondria to transcriptional regulation of metabolism through epigenetic control of PPARγ to promote metabolic remodeling in the developing heart. Collectively, this work positions SLC25A1 as a novel mitochondrial regulator of ventricular morphogenesis and cardiac metabolic maturation and suggests a role in congenital heart disease.

DOI: https://doi.org/10.1101/2023.05.22.541833