Disease relevance of HMGN4

• When purified anti-nucleus IgG molecules were introduced into FL cells by the erythrocyte-ghost fusion method with HVJ (Sendai virus), release of RNA from the nucleus into the cytoplasm was inhibited in the presence of alpha-amanitin, but nuclear accumulation of 125I-labeled non-histone chromosomal protein from the cytoplasm was not inhibited [1].
• Novel autoantigens of perinuclear anti-neutrophil cytoplasmic antibodies (P-ANCA) in ulcerative colitis: non-histone chromosomal proteins, HMG1 and HMG2 [2].
• Circulating immune complexes (CICs) in serum samples from patients with pulmonary tuberculosis (bacteriologically positive [S+C+] and bacteriologically negative [S-C-]) and controls (NHC) have been measured by using C1q binding assay (C1qBA) and 3.5% polyethylene glycol precipitation and measurement of absorbance at 280 nm (PEG-OD 280) [3].
• The effect of dexamethasone on the non-histone chromosomal proteins of hepatoma tissue culture cells [4].
• The high-mobility group protein HMGI(Y) is a member of a family of non-histone chromosomal proteins, which have been implicated in the regulation of inducible gene transcription, integration of retroviruses into chromosomes and induction of neoplastic transformation and metastatic progression in cancer cells [5].

High impact information on HMGN4

• Regulation of cell cycle stage-specific transcription of histone genes from chromatin by non-histone chromosomal proteins [6].
• Mammalian heterochromatin protein 1 (HP1) alpha, HP1beta and HP1gamma are closely related non-histone chromosomal proteins that function in gene silencing, presumably by organizing higher order chromatin structures [7].
• Here, we show that SP100 binds to members of the heterochromatin protein 1 (HP1) families of non-histone chromosomal proteins [8].
• Functionalised NHC comprise those carrying a phosphino-, amino-, imino- or oxygen-containing functionality on the imidazole sidechain [9].
• Whereas the functionalisation of the NHC has not improved their performance in catalysis, new developments have occurred in the use of imidazole-containing biomolecules such as l-histidine or caffeine as precursors for NHC [9].

Biological context of HMGN4

• A chicken genomic library was screened with the human cDNA encoding the non-histone chromosomal protein HMG-17 and a 4565-base pair fragment containing the entire gene encoding this protein was isolated and characterized [10].
• Human non-histone chromosomal protein HMG-17: identification, characterization, chromosome localization and RFLPs of a functional gene from the large multigene family [11].
• The human genome contains multiple copies of sequences homologous to the cDNA coding for non-histone chromosomal protein HMG-17 [12].
• It is shown here that the tyrosine at position 497 in the I4R is critical for regulation of the phosphorylation status of a set of nuclear proteins that includes HMG-I(Y), small non-histone chromosomal proteins involved in the control of gene expression in hematopoietic cell lines [13].
• The NHC proteins in seven different stable human-hamster cell lines, which, in total, contained markers for 21 of the 24 human chromosomes, were electrophoretically indistinguishable from those of the parental hamster cell line, with the exception of a single protein in one hybrid line [14].

Anatomical context of HMGN4

• The HMGN4 protein could be detected in HeLa cells by Western analysis with an antibody elicited against a unique region of the protein [15].
• Structural studies of the non-histone chromosomal proteins HMG-T and H6 from trout testis [16].
• It is concluded that many of the genes coding for the apparently human-specific NHC proteins are not expressed in these hybrid cells [14].
• The non-histone chromosomal protein HMG-I(Y) participates in repression of transcription directed by a promoter which confers interleukin 4 (IL-4)-inducible activation in transfected B cell lines [17].
• The infection and transformation of chick fibroblasts by RSV induced an increase in kinase activity and endogenous phosphorylation of non-histone chromosomal (NHC) proteins [18].

Associations of HMGN4 with chemical compounds

• Analysis of HeLa non-histone chromosomal protein by two-dimensional polyacrylamide gel electrophoresis has revealed more than 450 components, most of which are rare (less than 10,000 copies/cell) and are not detectable in cytoplasm [19].
• Modified (NHC)Pd(allyl)Cl (NHC = N-heterocyclic carbene) complexes for room-temperature Suzuki-Miyaura and Buchwald-Hartwig reactions [20].
• Less stable NHC carbenes can be conveniently obtained from imidazolium salts using the neutral base [Fe(II)Cp(eta(5)-C(6)Me(5)CH(2))] obtained from 1 and air [21].
• Facile migratory insertion of a N-heterocyclic carbene into a ruthenium-carbon double bond: a new type of reaction of a NHC ligand [22].
• The subsequent alcohol product can undergo an acylation event with the resulting acyl heteroazolium intermediate formed in situ between the NHC and the aldehyde [23].

Regulatory relationships of HMGN4

• We found that non-histone chromosomal high mobility group (HMG) proteins 1 and 2 enhanced the ligation of linearized pUC119 DNA with DNA ligase IV from rat liver nuclear extract [24].

Other interactions of HMGN4

• We describe a newly discovered nuclear protein, HMGN4, that is closely related to the canonical HMGN2 nucleosome-binding protein [15].
• The high mobility group A (HMGA) proteins are non-histone chromosomal proteins implicated in the organization of chromatin structure and in the assembly of protein complexes on the promoters of several inducible genes [25].
• Non-histone chromosomal proteins HMG1 and 2 enhance ligation reaction of DNA double-strand breaks [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 [26].
• In a previous study, we reported that the high mobility group (HMG) non-histone chromosomal proteins HMG1 and HMG2 were novel target antigens of P-ANCA [27].

Analytical, diagnostic and therapeutic context of HMGN4

• The non-histone chromosomal (NHC) proteins of several human and hamster cell lines as well as human-hamster cell hybrids were investigated by one- and two-dimensional gel electrophoresis [14].
• Average bone mineral densities (BMD) evaluated by dual-energy X-ray absorptiometry (DXA) in this study group did not differ from BMDs in healthy, NHC women of similar age [28].
• The loss of non-histone chromosomal proteins from cells that have been trypsinized causes changes in the structure of chromatin that can be detected by circular dichroism and by viscosity measurements [29].
• Application of this NHC silver complex to primary cultures of murine respiratory epithelial cells followed by microarray analysis showed minimal gene expression changes at the concentrations effective against respiratory pathogens [30].
• This indicates that reducing groups of non-histone chromosomal proteins are responsible for silver staining [31].

References