[Lys(Me2)9]-Histone H3 (1-21)-GGK(Biotin)-NH2

Product Name: [Lys(Me2)9]-Histone H3 (1-21)-GGK(Biotin)-NH2

Sequence One Letter Code: ARTKQTAR-K(Me2)-STGGKAPRKQLA-GGK(Biotin)-NH2

Sequence Three Letter Code: H-Ala-Arg-Thr-Lys-Gln-Thr-Ala-Arg-Lys(Me2)-Ser-Thr-Gly-Gly-Lys-Ala-Pro-Arg-Lys-Gln-Leu-Ala-Gly-Gly-Lys(Biotin)-NH2

Molecular Weight: 2750.4

Purity: 95%

Form: Lyophilized

Storage Conditions: - 20 °C

Research Area: epigenetics

Source / Species: human

Conjugation: Conjugated

Conjugation Type: Biotins

Code Nacres: NA.26

Application: [Lys(Me2)9]-Histone H3 (1–21)-GGK(Biotin) is a synthetic peptide corresponding to histone H3 residues 1–21 with dimethylation at lysine 9 (H3K9me2) and a C-terminal GG linker followed by a biotinylated lysine. H3K9me2 is an important epigenetic modification involved in facultative heterochromatin formation and transcriptional regulation. This histone mark is dynamically regulated during development and has been reported to exhibit sex-dependent patterns during meiotic prophase. The biotin tag enables affinity-based detection and interaction studies, allowing researchers to capture and characterize proteins that recognize H3K9 dimethylation. This peptide is widely used in studies of chromatin regulation, epigenetic plasticity, histone-binding proteins, and mechanisms controlling gene expression through histone methylation.

Current Research: Epigenetic regulation of gene expression is mediated in large part by post-translational modifications on histone proteins. These chemical marks influence chromatin structure, recruit regulatory proteins, and control the accessibility of DNA to transcriptional machinery. Among these modifications, dimethylation of lysine 9 on histone H3 (H3K9me2) plays a significant role in chromatin organization and transcriptional regulation. [Lys(Me2)9]-Histone H3 (1–21)-GGK(Biotin) is a synthetic histone peptide designed to replicate this epigenetic modification while incorporating a biotin tag that facilitates biochemical detection and affinity-based interaction studies. By reproducing the first 21 residues of the histone H3 N-terminal tail with dimethylation at lysine 9, this peptide provides researchers with a defined experimental model for studying proteins that recognize H3K9 methylation and regulate chromatin states. The Biological Role of H3K9 Dimethylation Histone H3 lysine 9 methylation occurs in multiple forms, including mono-, di-, and trimethylation, each associated with distinct chromatin environments. H3K9me2 is commonly linked to facultative heterochromatin, a chromatin state that is transcriptionally repressed but remains reversible depending on cellular context. Unlike constitutive heterochromatin—which remains permanently compacted—facultative heterochromatin allows cells to dynamically regulate gene expression. The H3K9me2 mark helps establish this intermediate chromatin environment by recruiting proteins that partially compact chromatin and limit transcriptional activity while still allowing regulatory flexibility. Genome-wide analyses have shown that H3K9me2 is broadly distributed across large genomic domains associated with developmentally regulated genes and tissue-specific transcription programs. Through these mechanisms, the modification contributes to the fine-tuning of gene expression during differentiation and cellular specialization. Structural Design of the Peptide The [Lys(Me2)9]-Histone H3 (1–21)-GGK(Biotin) peptide consists of three key structural components that enable its use in chromatin and epigenetics research. First, the peptide reproduces residues 1–21 of the histone H3 N-terminal tail, a region rich in regulatory modification sites and frequently targeted by histone-modifying enzymes. Within this sequence, lysine at position 9 is dimethylated, faithfully representing the H3K9me2 epigenetic mark found in chromatin. Second, a glycine–glycine (GG) linker is introduced at the C-terminus. This flexible linker helps reduce steric hindrance, allowing interacting proteins to access the histone sequence more easily. Finally, the peptide includes a biotinylated lysine residue at the C-terminus. The biotin modification enables strong binding to streptavidin or avidin-based surfaces, allowing the peptide to be immobilized for affinity purification and detection assays. This design ensures that the peptide maintains biological relevance while remaining compatible with a wide range of biochemical and proteomic experimental platforms. Investigating Proteins that Recognize H3K9me2 Histone modifications function as molecular signals that recruit chromatin-associated proteins containing specialized epigenetic reader domains. Proteins that recognize methylated lysine residues often contain domains such as chromodomains, Tudor domains, or MBT domains that selectively bind specific methylation states. The H3K9me2 modification is recognized by several chromatin regulatory proteins involved in gene repression and chromatin organization. These interactions contribute to the establishment of chromatin states that regulate transcriptional activity and genome stability. Using the biotinylated histone peptide, researchers can perform affinity pull-down experiments to capture proteins that bind specifically to the H3K9me2 mark. Once isolated, these proteins can be analyzed through immunodetection methods or mass spectrometry to identify components of chromatin regulatory complexes. Such studies help clarify how histone methylation signals are interpreted by cellular machinery and how these signals influence chromatin architecture. Applications in Chromatin and Epigenetics Research Because it reproduces a biologically important histone modification while incorporating a convenient affinity tag, [Lys(Me2)9]-Histone H3 (1–21)-GGK(Biotin) is widely used in epigenetics and chromatin biology research. Typical applications include: Affinity capture assays for isolating H3K9me2-binding proteins Protein–peptide interaction studies involving chromatin regulators Proteomic analysis of histone modification recognition complexes Biochemical assays investigating histone reader domain specificity Studies of chromatin remodeling and epigenetic signaling pathways These approaches allow researchers to better understand how histone methylation contributes to the regulation of gene expression and chromatin structure. H3K9me2 in Development and Epigenetic Plasticity The H3K9me2 modification is dynamically regulated during development and cellular differentiation, reflecting its role in controlling lineage-specific gene expression programs. Changes in H3K9me2 distribution can influence which genes are accessible for transcription and which remain repressed. Interestingly, studies of meiotic cells have reported sex-dependent patterns of H3K9me2 during meiotic prophase, suggesting that this histone mark may contribute to chromatin organization during gametogenesis. These findings highlight the broader importance of H3K9me2 in regulating genome architecture during specialized biological processes. Because histone methylation states can change in response to developmental signals or environmental cues, H3K9me2 is often studied in the context of epigenetic plasticity, the ability of cells to modify chromatin states while maintaining genome integrity. Advancing the Study of Histone Methylation Synthetic histone peptides remain powerful tools for dissecting the molecular mechanisms of epigenetic regulation. By faithfully reproducing the H3K9 dimethylation mark and incorporating a biotin tag for convenient detection, [Lys(Me2)9]-Histone H3 (1–21)-GGK(Biotin) enables researchers to investigate how chromatin-binding proteins interpret histone methylation signals. Through applications in interaction assays, chromatin studies, and proteomic analysis, this peptide supports research aimed at understanding histone modification recognition, chromatin organization, and gene expression control. As studies of epigenetic regulation continue to expand, reagents such as this peptide remain essential for uncovering how histone methylation shapes genome function across development and disease.