Gene/Protein
Disease
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Compound
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Gene/Protein
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Target Concepts:
Gene/Protein
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Query: UNIPROT:P10412 (
H1.4
)
75
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Histone post-translational modifications have been implicated in a variety of biological processes such as gene expression, DNA replication, and chromatin assembly. The modifications include methylation, acetylation, phosphorylation, ubiquitination, glycosylation, and ADP-ribosylation. For several years, we have been investigating the role of histone H1 phosphorylation in transcription using the hormone inducible mouse mammary tumor virus (MMTV) promoter. When mouse cells were exposed to prolonged treatment with dexamethasone, a significant decrease in the level of histone H1 phosphorylation was observed. Traditionally, Western analyses with anti-histone H1 and phospho-specific H1 antibodies were performed to observe changes in phosphorylation levels of the bulk H1 histones. More recently, we have applied electrospray ionization mass spectrometry to the analysis of histone H1 isoforms. Utilizing this approach, we have investigated the phosphorylation state of the specific H1 isoforms before and after prolonged treatment with dexamethasone. Specifically, we could determine that the relative phosphorylation levels of the
histone H1.3
,
H1.4
, and H1.5 isoforms decrease after prolonged hormone exposure. Recent advancements in mass spectrometry have proven invaluable toward the analysis of post-translational modifications on proteins. The continued developments in the area of mass spectrometry should provide new insights into not only the function of proteins but also into the basic regulatory mechanisms that control cellular functions.
...
PMID:Understanding global changes in histone H1 phosphorylation using mass spectrometry. 1503 87
Breast cancer was the second leading cause of cancer related mortality for females in 2014. Recent studies suggest histone H1 phosphorylation may be useful as a clinical biomarker of breast and other cancers because of its ability to recognize proliferative cell populations. Although monitoring a single phosphorylated H1 residue is adequate to stratify high-grade breast tumors, expanding our knowledge of how H1 is phosphorylated through the cell cycle is paramount to understanding its role in carcinogenesis. H1 analysis by bottom-up MS is challenging because of the presence of highly homologous sequence variants expressed by most cells. These highly basic proteins are difficult to analyze by LC-MS/MS because of the small, hydrophilic nature of peptides produced by tryptic digestion. Although bottom-up methods permit identification of several H1 phosphorylation events, these peptides are not useful for observing the combinatorial post-translational modification (PTM) patterns on the protein of interest. To complement the information provided by bottom-up MS, we utilized a top-down MS/MS workflow to permit identification and quantitation of H1 proteoforms related to the progression of breast cells through the cell cycle. Histones H1.2 and
H1.4
were observed in MDA-MB-231 metastatic breast cells, whereas an additional histone variant,
histone H1.3
, was identified only in nonneoplastic MCF-10A cells. Progressive phosphorylation of
histone H1.4
was identified in both cell lines at mitosis (M phase). Phosphorylation occurred first at S172 followed successively by S187, T18, T146, and T154. Notably, phosphorylation at S173 of histone H1.2 and S172, S187, T18, T146, and T154 of
H1.4
significantly increases during M phase relative to S phase, suggesting that these events are cell cycle-dependent and may serve as markers for proliferation. Finally, we report the observation of the H1.2 SNP variant A18V in MCF-10A cells.
...
PMID:Quantitative Mass Spectrometry Reveals that Intact Histone H1 Phosphorylations are Variant Specific and Exhibit Single Molecule Hierarchical Dependence. 2620 8