CXXC finger protein 1-mediated histone H3 lysine-4 trimethylation is essential for proper meiotic crossover formation in mice.

The most significant feature of meiosis is the recombination process during prophase I. CXXC finger protein 1 (CXXC1) binds to CpG islands and mediates the deposition of H3K4me3 by the SETD1 complex. CXXC1 is also predicted to recruit H3K4me3-marked regions to the chromosome axis for the generation of double-strand breaks (DSBs) in the prophase of meiosis. Therefore, we deleted Cxxc1 before the onset of meiosis with Stra8-Cre The conditional knockout mice were completely sterile with spermatogenesis arrested at MII. Knockout of Cxxc1 led to a decrease in the H3K4me3 level from the pachytene to the MII stage and caused transcriptional disorder. Many spermatogenesis pathway genes were expressed early leading to abnormal acrosome formation in arrested MII cells. In meiotic prophase, deletion of Cxxc1 caused delayed DSB repair and improper crossover formation in cells at the pachytene stage, and more than half of the diplotene cells exhibited precocious homologous chromosome segregation in both male and female meiosis. Cxxc1 deletion also led to a significant decrease of H3K4me3 enrichment at DMC1-binding sites, which might compromise DSB generation. Taken together, our results show that CXXC1 is essential for proper meiotic crossover formation in mice and suggest that CXXC1-mediated H3K4me3 plays an essential role in meiotic prophase of spermatogenesis and oogenesis.

Analyzing the impact of CFP1 mutational landscape on epigenetic signaling.

CXXC Zinc finger protein 1 (CFP1) is a multitasking protein playing essential roles during various developmental processes. Its ability to interact with several proteins contribute to several epigenetic events. Here, we review CFP1's functions and its impact on DNA methylation and the post-translational modification of histone proteins such as lysine acetylation and methylation. We will also discuss the potential role of CFP1 in carcinogenesis and the impact of the mutations identified in patients suffering from various cancers.

The survival analysis and oncogenic effects of CFP1 and 14-3-3 expression on gastric cancer.

BACKGROUND & AIM: Gastric cancer (GC) is the third-leading cause of cancer-related deaths. We established a prospective database of patients with GC who underwent surgical treatment. In this study, we explored the prognostic significance of the expression of CFP1 and 14-3-3 in gastric cancer, by studying the specimens collected from clinical subjects. MATERIALS & METHODS: Immunohistochemistry was used to detect the expression of CFP1 and 14-3-3 in 84 GC subjects, including 73 patients who have undergone radical gastrectomy and 11 patients who have not undergone radical surgery. Survival analysis was performed by km-plot data. RESULTS: According to the survival analysis, we can see that the survival time of patients with high expression of CFP1 is lower than the patients with low expression in gastric cancer, while the effect of 14-3-3 is just the opposite. The survival time of patients with higher expression of 14-3-3 is also longer. CONCLUSION: The CFP1 and 14-3-3 genes can be used as prognostic markers in patients with GC, but the study is still needed to confirm.

Is H3K4me3 instructive for transcription activation?

Tri-methylation of lysine 4 on histone H3 (H3K4me3) is a near-universal chromatin modification at the transcription start site of active genes in eukaryotes from yeast to man and its levels reflect the amount of transcription. Because of this association, H3K4me3 is often described as an 'activating' histone modification and assumed to have an instructive role in the transcription of genes, but the field is lacking a conserved mechanism to support this view. The overwhelming finding from genome-wide studies is that actually very little transcription changes upon removal of most H3K4me3 under steady-state or dynamically changing conditions, including at mammalian CpG island promoters. Instead, rather than a major role in instructing transcription, time-resolved experiments provide more evidence supporting the deposition of H3K4me3 into chromatin as a result of transcription, influencing processes such as memory of previous states, transcriptional consistency between cells in a population and transcription termination.

CRISPR system in the yeast Saccharomyces cerevisiae and its application in the bioproduction of useful chemicals.

Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) immune systems in bacteria have been used as tools for genome engineering. Thus far, the CRISPR-Cas system has been used in various yeast, bacterial, and mammalian cells. Saccharomyces cerevisiae is a nonpathogenic yeast, classified under "generally recognized as safe", and has long been used to produce consumables such as alcohol or bread. Additionally, recombinant cells of S. cerevisiae have been constructed and used to produce various bio-based chemicals. Some types of CRISPR-Cas system for genetic manipulation have been constructed during the early developmental stages of the CRISPR-Cas system and have been mainly used for gene knock-in and knock-out manipulations. Thereafter, these systems have been used for various novel purposes such as metabolic engineering and tolerance engineering. In this review, we have summarized different aspects of the CRISPR-Cas in the yeast S. cerevisiae, from its basic principles to various applications. This review describes the CRISPR system in S. cerevisiae based on the differences in its origin and efficiency followed by its basic applications; for example, its involvement in gene knock-in and knock-out has been outlined. Finally, advanced applications of the CRISPR system in the bioproduction of useful chemicals have been summarized.

Cfp1 Controls Cardiomyocyte Maturation by Modifying Histone H3K4me3 of Structural, Metabolic, and Contractile Related Genes.

Cardiomyocyte maturation is the final stage of heart development, and abnormal cardiomyocyte maturation will lead to serious heart diseases. CXXC zinc finger protein 1 (Cfp1), a key epigenetic factor in multi-lineage cell development, remains underexplored in its influence on cardiomyocyte maturation. This study investigates the role and mechanisms of Cfp1 in this context. Cardiomyocyte-specific Cfp1 knockout (Cfp1-cKO) mice died within 4 weeks of birth. Cardiomyocytes derived from Cfp1-cKO mice showed an inhibited maturation phenotype, characterized by structural, metabolic, contractile, and cell cycle abnormalities. In contrast, cardiomyocyte-specific Cfp1 transgenic (Cfp1-TG) mice and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) overexpressing Cfp1 displayed a more mature phenotype. Mechanistically, deficiency of Cfp1 led to a reduction in trimethylation on lysine 4 of histone H3 (H3K4me3) modification, accompanied by the formation of ectopic H3K4me3. Furthermore, Cfp1 deletion decreased the level of H3K4me3 modification in adult genes and increased the level of H3K4me3 modification in fetal genes. Collectively, Cfp1 modulates the expression of genes crucial to cardiomyocyte maturation by regulating histone H3K4me3 modification, thereby intricately influencing the maturation process. This study implicates Cfp1 as an important molecule regulating cardiomyocyte maturation, with its dysfunction strongly linked to cardiac disease.

CFP-1 interacts with HDAC1/2 complexes in C. elegans development.

CXXC finger binding protein 1 (CFP-1) is an evolutionarily conserved protein that binds to non-methylated CpG-rich promoters in mammals and Caenorhabditis elegans. This conserved epigenetic regulator is part of the COMPASS complex that contains the H3K4me3 methyltransferase SET1 in mammals and SET-2 in C. elegans. Previous studies have indicated the importance of CFP1 in embryonic stem cell differentiation and cell fate specification. However, neither the function nor the mechanism of action of CFP1 is well understood at the organismal level. Here, we have used cfp-1(tm6369) and set-2(bn129) C. elegans mutants to investigate the function of CFP-1 in gene induction and development. We have characterised C. elegansCOMPASS mutants cfp-1(tm6369) and set-2(bn129) and found that both cfp-1 and set-2 play an important role in the regulation of fertility and development of the organism. Furthermore, we found that both cfp-1 and set-2 are required for H3K4 trimethylation and play a repressive role in the expression of heat shock and salt-inducible genes. Interestingly, we found that cfp-1 but not set-2 genetically interacts with histone deacetylase (HDAC1/2) complexes to regulate fertility, suggesting a function of CFP-1 outside of the COMPASS complex. Additionally, we found that cfp-1 and set-2 independently regulate fertility and development of the organism. Our results suggest that CFP-1 genetically interacts with HDAC1/2 complexes to regulate fertility, independent of its function within the COMPASS complex. We propose that CFP-1 could cooperate with the COMPASS complex and/or HDAC1/2 in a context-dependent manner.

CpG binding protein (CFP1) occupies open chromatin regions of active genes, including enhancers and non-CpG islands.

BACKGROUND: The mechanism by which protein complexes interact to regulate the deposition of post-translational modifications of histones remains poorly understood. This is particularly important at regulatory regions, such as CpG islands (CGIs), which are known to recruit Trithorax (TrxG) and Polycomb group proteins. The CxxC zinc finger protein 1 (CFP1, also known as CGBP) is a subunit of the TrxG SET1 protein complex, a major catalyst of trimethylation of H3K4 (H3K4me3). RESULTS: Here, we used ChIP followed by high-throughput sequencing (ChIP-seq) to analyse genomic occupancy of CFP1 in two human haematopoietic cell types. We demonstrate that CFP1 occupies CGIs associated with active transcription start sites (TSSs), and is mutually exclusive with H3K27 trimethylation (H3K27me3), a marker of polycomb repressive complex 2. Strikingly, rather than being restricted to active CGI TSSs, CFP1 also occupies a substantial fraction of active non-CGI TSSs and enhancers of transcribed genes. However, relative to other TrxG subunits, CFP1 was specialised to TSSs. Finally, we found enrichment of CpG-containing DNA motifs in CFP1 peaks at CGI promoters. CONCLUSIONS: We found that CFP1 is not solely recruited to CpG islands as it was originally defined, but also other regions including non-CpG island promoters and enhancers.

DNA Sequence Recognition of Human CXXC Domains and Their Structural Determinants.

The CXXC domain, first identified as the reader of unmodified CpG dinucleotide, plays important roles in epigenetic regulation by targeting various activities to CpG islands. Here we systematically measured and compared the DNA-binding selectivities of all known human CXXC domains by different binding assays, and complemented the existing function-based classification of human CXXC domains with a classification based on their DNA selectivities. Through a series of crystal structures of CXXC domains with DNA ligands, we unravel the molecular mechanisms of how these CXXC domains, including single CXXC domains and tandem CXXC-PHD domains, recognize distinct DNA ligands, which further supports our classification of human CXXC domains and also provides insights into selective recruitment of chromatin modifiers to their respective targets via CXXC domains recognizing different genomic DNA sequences. Our study facilitates the understanding of the relationship between the DNA-binding specificities of the CXXC proteins and their biological functions.