[24] Purification and analysis of H1 histones

Rd, Cole

doi:10.1016/0076-6879(89)70062-8

Cited by 22 publications

(16 citation statements)

References 18 publications

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“…2 are within the expected range given the amounts of histone H1 and nucleosomes in the chromatin assembly reaction mixtures. The differences from the predicted values are likely due to the fact that histone H1 concentrations are difficult to determine accurately (8), as well as the fact that the number of nucleosomes in the chromatin assembly reaction mixtures is an estimate.…”

Section: Resultsmentioning

confidence: 98%

Histone H1 Represses Estrogen Receptor α Transcriptional Activity by Selectively Inhibiting Receptor-Mediated Transcription Initiation

Cheung

Zarifyan

Kraus

2002

Molecular and Cellular Biology

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Chromatin is the physiological template for many nuclear processes in eukaryotes, including transcription by RNA polymerase II. In vivo, chromatin is assembled from genomic DNA, core histones, linker histones such as histone H1, and nonhistone chromatin-associated proteins. Histone H1 is thought to act as a general repressor of transcription by promoting the compaction of chromatin into higher-order structures. We have used a biochemical approach, including an in vitro chromatin assembly and transcription system, to examine the effects of histone H1 on estrogen receptor ␣ (ER␣)-mediated transcription with chromatin templates. We show that histone H1 acts as a potent repressor of ligand-and coactivator-regulated transcription by ER␣. Histone H1 exerts its repressive effect without inhibiting the sequence-specific binding of ER␣ to chromatin or the overall extent of targeted acetylation of nucleosomal histones by the coactivator p300. Instead, histone H1 acts by blocking a specific step in the ER␣-dependent transcription process, namely, transcription initiation, without affecting transcription reinitiation. Together, our data indicate that histone H1 acts selectively to reduce the overall level of productive transcription initiation by restricting promoter accessibility and preventing the ER␣-dependent formation of a stable transcription preinitiation complex.Chromatin is the physiological template for many nuclear processes in eukaryotes, including transcription, replication, and repair of the genome. The assembly of genomic DNA into chromatin has important functional consequences for the regulation of RNA polymerase II (pol II)-encoding genes since chromatin acts as a general repressor of transcription. Sequence-specific DNA-binding activator proteins, ATP-dependent chromatin-remodeling complexes, and coactivators are required to overcome chromatin-mediated transcriptional repression (23). Transcriptional activator proteins target chromatin-remodeling complexes and coactivators to specific promoters. Chromatin-remodeling complexes use the energy from ATP to reorganize chromatin at the promoters, which allows access of the promoter DNA to the basal transcriptional machinery (reviewed in reference 26). Coactivators have at least two roles (reviewed in references 35 and 53). First, those coactivators with intrinsic histone acetyltransferase (HAT) activity acetylate nucleosomal histones at the promoter, which is thought to facilitate chromatin remodeling. Second, coactivators can make contacts with the basal transcriptional machinery and RNA pol II to facilitate the formation of transcription preinitiation complexes (PICs). The concerted actions of the activators, chromatin-remodeling complexes, and coactivators lead to the transcription of genes assembled into chromatin (reviewed in references 16, 23, 26, 34, and 35).Chromatin is assembled in vivo from genomic DNA, core histones, linker histones, and nonhistone chromatin-associated proteins. The core histones form the structural core of the nucleosome (38), wherea...

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Section: Resultsmentioning

confidence: 98%

Histone H1 Represses Estrogen Receptor α Transcriptional Activity by Selectively Inhibiting Receptor-Mediated Transcription Initiation

Cheung

Zarifyan

Kraus

2002

Molecular and Cellular Biology

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“…Histone H1 is a major target protein modified by PARP (36,37). In an attempt to confirm histone H1 poly(ADPribosyl)ation, we extracted histone H1 from UV-treated cells (31), and analyzed its state of poly(ADP-ribosyl)ation. Histone H1 was markedly poly(ADP-ribosyl)ated by 2 h after UV irradiation (Fig.…”

Section: Resultsmentioning

confidence: 99%

“…Analysis of the Poly(ADP-ribosyl)ation of Histone H1-Cells were permeabilized for the poly(ADP-ribosyl)ation reaction as described earlier, and histone H1 was extracted by a modified version of the method of Cole (31). Briefly, perchloric acid was added to each cell sample in a 100-mm culture dish (5% final concentration).…”

mentioning

confidence: 99%

Poly(ADP-ribosyl)ation of Histone H1 Correlates with Internucleosomal DNA Fragmentation during Apoptosis

Yoon

Kim

Kang

et al. 1996

Journal of Biological Chemistry

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The biochemical role of poly(ADP-ribosyl)ation on internucleosomal DNA fragmentation associated with apoptosis was investigated in HL 60 human premyelocytic leukemia cells. It was found that UV light and chemotherapeutic drugs including adriamycin, mitomycin C, and cisplatin increased poly(ADP-ribosyl)ation of nuclear proteins, particularly histone H1. A poly(ADP-ribose) polymerase inhibitor, 3-aminobenzamide, prevented both internucleosomal DNA fragmentation and histone H1 poly(ADP-ribosyl)ation in cells treated with the apoptosis inducers. When nuclear chromatin was made accessible to the exogenous nuclease in a permeabilized cell system, chromatin of UV-treated cells was more susceptible to micrococcal nuclease than the chromatin of control cells. Suppression of histone H1 poly-(ADP-ribosyl)ation by 3-aminobenzamide reduced the micrococcal nuclease digestibility of internucleosomal chromatin in UV-treated cells. These results suggest that the poly(ADP-ribosyl)ation of histone H1 correlates with the internucleosomal DNA fragmentation during apoptosis mediated by DNA damaging agents. This suggestion is supported by the finding that xeroderma pigmentosum cells which are defective in introducing incision at the site of DNA damage, failed to induce DNA fragmentation as well as histone H1 poly(ADP-ribosyl)ation after UV irradiation. We propose that poly(ADPribosyl)ation of histone H1 protein in the early stage of apoptosis facilitates internucleosomal DNA fragmentation by increasing the susceptibility of chromatin to cellular endonuclease.Apoptosis is an active form of cellular suicide, a process that typically involves morphological changes such as the condensation of chromatin into clumps, nuclear fragmentation, and packaging of nuclear fragments into membrane-enclosed apoptotic bodies. These morphological changes are usually accompanied by biochemical changes including elevation of cytoplasmic Ca 2ϩ and internucleosomal DNA fragmentation (1). Many of the chemotherapeutic drugs and radiation which cause DNA damage are known to induce apoptosis (2-5). It is well established that a variety of DNA damaging agents lower the cellular NAD ϩ content by raising the specific activity of poly(ADPribose) polymerase (PARP) 1 (EC 2.4.2.30) that results from the conformational changes which occur when the zinc finger domains of the enzyme bind to the DNA strand breaks (6, 7). PARP is a nuclear enzyme which transfers the ADP-ribose moiety of NAD ϩ to nuclear proteins including PARP itself and histones in cells (8). In vitro studies have also revealed that topoisomerase I (9), RNA polymerase II (10), DNA polymerase ␣ (11), DNA polymerase ␤ (12), and terminal deoxynucleotidyl transferase (13) are the substrates of PARP. Thus, poly(ADPribosyl)ation has been implicated in many biological responses including DNA replication (14), DNA excision repair (15), cell differentiation (16), and tumor promotion (17).In recent years, the role of poly(ADP-ribosyl)ation in the cell death process has been discussed. The decrease in cellular PARP ...

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“…Selective extractability with 5% perchloric acid (PCA) is a distinctive property of linker histones (Cole, 1989). Using acetic acid-urea PAGE, we analyzed nuclei extracted with 5% PCA from various tobacco tissues and detected two major and four minor histone bands ( Figure 1A).…”

Section: Identification Of Linker Histone Variants In Tobaccomentioning

confidence: 99%

Linker Histones Play a Role in Male Meiosis and the Development of Pollen Grains in Tobacco

et al. 1999

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To examine the function of linker histone variants, we produced transgenic tobacco plants in which major somatic histone variants H1A and H1B were present at ‫ف‬ 25% of their usual amounts in tobacco chromatin. The decrease in these major variants was accompanied by a compensatory increase in the four minor variants, namely, H1C to H1F. These minor variants are smaller and less highly charged than the major variants. This change offered a unique opportunity to examine the consequences to a plant of major remodeling of its chromatin set of linker histones. Plants with markedly altered proportions of H1 variants retained normal nucleosome spacing, but their chromosomes were less tightly packed than those of control plants. The transgenic plants grew normally but showed characteristic aberrations in flower development and were almost completely male sterile. These features correlated with changes in the temporal but not the spatial pattern of expression of developmental genes that could be linked to the abnormal flower phenotypes. Preceding these changes in flower morphology were strong aberrations in male gametogenesis. The earliest symptoms may have resulted from disturbances in correct pairing or segregation of homologous chromosomes during meiosis. No aberrations were observed during mitosis. We conclude that in plants, the physiological stoichiometry and distribution of linker histone variants are crucial for directing male meiosis and the subsequent development of functional pollen grains.

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[24] Purification and analysis of H1 histones

Cited by 22 publications

References 18 publications

Histone H1 Represses Estrogen Receptor α Transcriptional Activity by Selectively Inhibiting Receptor-Mediated Transcription Initiation

Histone H1 Represses Estrogen Receptor α Transcriptional Activity by Selectively Inhibiting Receptor-Mediated Transcription Initiation

Poly(ADP-ribosyl)ation of Histone H1 Correlates with Internucleosomal DNA Fragmentation during Apoptosis

Linker Histones Play a Role in Male Meiosis and the Development of Pollen Grains in Tobacco

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