Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10412 (H1.4)
 75 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

High-performance capillary electrophoresis (HPCE) was used to separate successfully distinct phosphorylated derivatives of individual histone H1 variants. With an untreated capillary (50 cm x 75 microns I.D.) the electrophoresis was performed in about 15 min. Inconvenient interactions of these highly basic proteins with the capillary wall were eliminated by using 0.1 M sodium phosphate buffer (pH 2.0) containing 0.03% hydroxypropylmethylcellulose. Under these experimental conditions the histone H1 variants H1b and H1c obtained from mitotic enriched NIH 3T3 fibroblasts and isolated by reversed-phase high-performance liquid chromatography were clearly separated in their non-phosphorylated and different phosphorylated forms. This result was confirmed by acid-urea gel electrophoresis, comparison with non-phosphorylated histones H1b and H1c, isolated from quiescent NIH 3T3 cells, and incubation of multi-phosphorylated histone H1b with alkaline phosphatase and subsequent acid-urea and capillary electrophoresis. The results illustrate that the application of HPCE to the analysis of histone modifications provides a new alternative to traditional gel electrophoresis.
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PMID:Separation of phosphorylated histone H1 variants by high-performance capillary electrophoresis. 143 24

The H1 histones serve as general repressors of gene expression by inducing the formation of a compact chromatin structure, whereas the high-mobility-group (HMG) non-histone chromosomal proteins have roles in maintaining the structure and function of transcriptionally active chromatin. The distribution of the H1 histone subtypes and HMG proteins among various trout tissues (liver, hepatocellular carcinoma, testis and erythrocyte) was determined. Histone H1b was present in the chromatin of liver, but not in the chromatin of hepatocellular carcinoma, testis or erythrocyte. Nuclease-resistant regions of liver chromatin had elevated levels of histone H1b. Histone H1b was isolated, and the N-terminal amino acid sequence of histone H1b was found to be highly similar to that of mammalian histone H1(0) and duck H5. HMG proteins T1, T2, T3, H6, C, D and F were associated with liver and hepatocellular-carcinoma chromatin, with hepatocellular carcinoma containing higher levels of HMG T1 and F. Testis and erythrocyte had HMG T2 and H6 as their predominant HMG proteins. Most of the HMG H6 of hepatocellular carcinoma, but not of liver, was located in a chromatin fraction that was soluble at physiological ionic strength and enriched in transcriptionally active DNA. These alterations in the chromatin distribution and content of hepatocyte HMG proteins and H1 histone subtypes may contribute to aberrant hepatocyte gene expression in the hepatocellular carcinoma.
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PMID:Characterization and chromatin distribution of the H1 histones and high-mobility-group non-histone chromosomal proteins of trout liver and hepatocellular carcinoma. 174 24

Histone H1 from erythrocytes of Japanese quail was resolved in a sodium dodecyl sulfate (SDS)-polyacrylamide gel into five fractions differing in apparent molecular weights. A polymorphism of histone H1.1, H1.2, and H1.3 bands was detected among quail individuals. While some birds possessed either a high (phenotype .3+) or a low (phenotype .3+/.3-) level of H1.3, at least half of the quail population lacked this H1 band (phenotype .3-). Appropriate genetic crosses demonstrated that H1.3 behaved as though it was coded by a gene with two codominant alleles at an autosomal locus. Using two-dimensional polyacrylamide gel electrophoresis (acid-urea followed by SDS gels), it was found that birds .3+ contained polypeptides H1.b1 and H1.b'1; birds .3-, polypeptides H1.b2 and H1.b'2 with lower apparent molecular weights; and birds .3+/.3-, both types of polypeptides in equal proportions. The H1.b2 + H1.b'2 complement was not discernible in SDS gels, for it migrated together with H1.c' within band H1.4. It was found that a small number of birds lacking the H1.2 band in SDS gels failed to express histone H1.a. Since birds with phenotype .2- with a defective allele of the gene H1.a were simultaneously lacking the H1.3 band, it seems that the imperfect allele of the H1.a gene might be closely linked to the alleles producing H1.b2 + H1.b'2.
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PMID:Genetic polymorphism of erythrocyte histone H1 in Japanese quail. 177

Inhibitory activity on renal membrane adenylate cyclase (AC) has previously been found in the extract of a pancreatic cancer associated with humoral hypercalcemia of malignancy (HHM). AC inhibitor was purified employing inhibition of AC activity of renal membrane stimulated by forskolin as its index. N-terminal 9 residues and a digested fragment of purified protein (14 residues) were completely consistent with that of histones H1b and H1d. Not only histone H1 but also histones H2A, H2B and H3 from calf thymus inhibited AC activity. These results indicate that the AC inhibitor in the pancreatic cancer extract is histone H1b or H1d and histones H2A, H2B and H3 also have an AC inhibitory activity.
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PMID:Purification and partial sequencing of inhibitory factor on renal membrane adenylate cyclase in pancreatic cancer extract: identity with histones H1b or H1d. 201 21

The amino acid sequences of the two variants (H1a 121 residues and H1b 119 residues) of the sperm-specific histone H1 from the polychaete annelid Platynereis dumerilii have been completely established. Comparison of the sequences of these two variants shows one deletion of two residues in histone H1b and 22 substitents, of which most occur in the globular domain. The two variants differ highly in a sequence of nine residues adjacent to the conservative phenylalanine residue of histone H1 (64-72 in H1a, 62-70 in H1b) which makes H1a less hydrophobic than H1b. The small molecular size of Platynereis H1a and H1b is a unique feature among the histones H1 of which the size ranges between 189 residues (chicken erythrocyte H5) and 248 residues (sea urchin sperm H1). H1a and H1b have short N- and C-terminal basic domains but the size of the globular domain (approximately equal to 80 residues) is similar to that of other H1s. In the globular region the variant H1a exhibits a close relationship with somatic or sperm H1s whereas the variant H1b is more related to H5 histones.
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PMID:Primary structure of the two variants of a sperm-specific histone H1 from the annelid Platynereis dumerilii. 401 88

Chromatin fragments stripped of H1 histones regain the ability to form higher order structures and aggregates in 0.15 M NaCl following reconstitution with histone H1. However, transcriptionally competent chromatin fragments are resistant to chicken erythrocyte H1/H5 histone-induced 0.15 M NaCl aggregation/precipitation. In this study, we investigated the ability of stripped chromatin fragments reconstituted with one of four histone H1 subtypes (chicken erythrocyte H1, H5, trout liver H1a, H1b) at various stoichiometries to form salt precipitable higher order structures. Our results provide evidence that chicken erythrocyte histone H1 was more effective than histone H5 and trout liver histone H1b better than H1a in forming higher order structures. None of the histone H1 subtypes could render transcriptionally competent chromatin fragments insoluble in 0.15 M NaCl. These results are consistent with the ideas that the histone H1 subtypes differ in their capacities to compact chromatin fiber, and that the alterations in the structure of transcriptionally competent nucleosomes interfere with the capacity of all H1 subtypes to form higher order structures.
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PMID:Differential compaction of transcriptionally competent and repressed chromatin reconstituted with histone H1 subtypes. 784 Nov 98

Our goal was to purify and characterize the allelic variants H1b1 and H1b2 of histone H1.b, one of the seven subtypes of this linker histone extracted from Japanese quail erythrocyte nuclei. These variants are revealed phenotypically as band H1.3 or part of band H1.4 by polyacrylamide gel electrophoresis (PAGE) in sodium dodecyl sulfate (SDS). All H1 subtypes together were separated from H5 by gel-permeation chromatography through Bio-Gel P-150. H1 was then fractionated on a column of the cation-exchange resin Amberlite CG-50 by using a shallow guanidine hydrochloride gradient, which enriched subtype H1.b together with H1.z and overlapping with subtypes H1.a and H1.b. Alternatively purification of subtypes was achieved electrophoretically: total H1 fractions from quail with different H1 phenotypes were first resolved into sub-types by PAGE in acetic acid-urea; after staining, the appropriate H1.b bands from several parallel gel pieces were excised and the histone was concentrated by PAGE in SDS. After fragmentation of H1.b in the gel pieces with N-bromosuccinimide (NBS), PAGE in SDS indicated no difference between H1b1 and H1b2 in the C-terminal "half" of the polypeptides. In contrast, limited digestion with endoprotease V8 from Staphylococcus aureus has shown that differences, probably by a few residues in length, reside in the N-terminal part of the molecule, close to the amino-terminus.
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PMID:Isolation and preliminary characterization of histone H1.b allelic variants from quail erythrocytes. 980 40

Characteristic steps in the course of cellular apoptosis are the induction of chromatin condensation and cleavage of the DNA, leading to the formation of oligomers of nucleosomes. Since the H1 histones represent functional elements that are essential for the generation of highly condensed chromatin structures, we analysed the total cellular H1 histones of five leukaemic and three solid human tumour cell lines, comparing the H1 pattern of exponentially growing cells with that of apoptotic cells. For the induction of apoptosis, cell lines were treated with the water-soluble camptothecin derivative, topotecan (a topoisomerase I inhibitor), or with an apoptosis-inducing monoclonal anti-CD95 (Fas/APO-1) antibody. Total histone H1 proteins were isolated by extraction with 5% perchloric acid and were analysed by means of capillary zone electrophoresis (CZE) separation. The identities of the peaks representing different histone H1 subtypes on CZE electropherograms were confirmed by analysis of preparations (recombinant proteins purified from transformed yeast used as internal standards) mixed with each of the subtypes respectively. The progress of topotecan- or anti-CD95-induced cell death was monitored by flow cytometry analysis and also by agarose electrophoresis of fragmented DNA. During early apoptosis of three of these cell lines, we observed the induction of internucleosomal DNA cleavage and, simultaneously, a typical change in the histone H1 protein pattern, leading to an increase in the relative amounts of histone subtypes H1.4 and H1.5. Upon apoptosis induction, these changes were only observed in correlation with the occurrence of DNA fragmentation, thus possibly reflecting a prerequisite for DNA accessibility and/or endonuclease activity.
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PMID:Changes in the protein pattern of H1 histones associated with apoptotic DNA fragmentation. 988 31

We have previously shown a connection between histone H1 phosphorylation and the transcriptional competence of the hormone inducible mouse mammary tumor virus (MMTV) promoter. Prolonged exposure of mouse cells to dexamethasone concurrently dephosphorylated histone H1 and rendered the MMTV promoter refractory to hormonal stimulation and, therefore, transcriptionally unresponsive. Using electrospray mass spectrometry, we demonstrate here that prolonged dexamethasone treatment differentially effects a subset of the six somatic H1 isoforms in mouse cells. H1 isoforms H1.0, H1.1, and H1.2 are non-responsive to hormone whereas prolonged dexamethasone treatment effectively dephosphorylated the H1.3, H1.4, and H1.5 isoforms. The protein kinase inhibitor staurosporine, shown to dephosphorylate histone H1 and down-regulate MMTV in cultured cells, appears only to completely dephosphorylate the H1.3 isoform. These results suggest that dephosphorylation of specific histone H1 isoforms may contribute to the previously observed decrease in transcriptional competence of the MMTV promoter through the modulation of chromatin structure. In a broader sense, this work advances the hypothesis that post-translational modifications of individual histone H1 isoforms directly influence the transcriptional activation/repression of specific genes.
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PMID:Hormone-mediated dephosphorylation of specific histone H1 isoforms. 1147 99

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.
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PMID:Understanding global changes in histone H1 phosphorylation using mass spectrometry. 1503 87


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