Disease relevance of His1:CG31617

• However, in An. stephensi rpS6 the extension was approximately 70 amino acids longer than that in Ae. albopictus, and at the nucleotide level, it most closely resembled histone H1 proteins from the unicellular eukaryotes Leishmania and Chlamydomonas, and the bacterium Bordetella pertussis [1].

High impact information on His1:CG31617

• Inasmuch as activation also took place after histone H1 depletion, this histone does not appear to be essential for this step of gene activation [2].
• TAFII250 mediates monoubiquitination of histone H1 in vitro [3].
• Sequence-specific antirepression of histone H1-mediated inhibition of basal RNA polymerase II transcription [4].
• Here we provide evidence that specific components of Drosophila melanogaster ribosomes copurify with linker histone H1 [5].
• Overexpression of either histone H1 or ribosomal protein L22 in Drosophila cells resulted in global suppression of the same set of genes, while depletion of H1 and L22 caused up-regulation of tested genes, suggesting that H1 and ribosomal proteins are essential for transcriptional gene repression [5].

Biological context of His1:CG31617

• We then mimicked DNA replication and chromatin assembly at a replication fork and found that Gal4-VP16 could potentiate transcription during, but not after, replication and assembly of histone H1-containing chromatin [6].
• RNA polymerase (RNA nucleotidyltransferase) B (or II) and histone H1 of Drosophila melanogster were localized on salivary gland polytene chromosomes using the indirect immunofluorescence technique [7].
• Phosphorylation of histone H1 is developmentally regulated in Drosophila spp [8].
• HMG-D and histone H1 interplay during chromatin assembly and early embryogenesis [9].
• The repeat unit has a size of 5.1 x 10(3) base-pairs and contains one copy of each of the genes coding for the core histones and one copy coding for the histone H1 [10].

Anatomical context of His1:CG31617

• Moreover, we show that the gypsy insulator, like previously characterized MAR/SARs, specifically interacts with topoisomerase II and histone H1, i.e. with two essential components of the nuclear matrix [11].
• By means of indirect immunofluorescence microscopy, we have studied the distribution of RNA polymerase B, of the nucleosomal histones H2b, H3, and H4 and of histone H1, in nuclei of primary spermatocytes of Drosophila hydei [12].
• These data indicate that PtdIns(4,5)P2 bound to nuclear protein histone H1 may contribute to the regulation of transcription in eukaryotic cells [13].
• To explore homology between a mosquito H1 histone and the RPS6 tail, we took advantage of the Anopheles gambiae genome database to clone a histone H1 gene from an Anopheles stephensi mosquito cell line [14].

Associations of His1:CG31617 with chemical compounds

• One of these is histone H1, and we refer to the other two as A63 and A13 in accordance with their molecular weights determined by electrophoresis on sodium dodecyl sulfate (NaDodSO4)-polyacrylamide gels (63,000 and 13,000, respectively) [15].
• Phosphatidylinositol 4,5-bisphosphate reverses the inhibition of RNA transcription caused by histone H1 [13].
• Histone H1-like, lysine-rich low complexity amino acid extensions in mosquito ribosomal proteins RpL23a and RpS6 have evolved independently [16].
• 0. This folding is achieved only through ionization of acidic side chains which leads to an environment of the tyrosine residues similar to that found in salt-folded histone H1 [17].
• This region had homology to cDNAs encoding histone H1 from various species and accounted for the larger size of the mosquito protein on polyacrylamide gels [18].

Physical interactions of His1:CG31617

• Furthermore, HP1alpha interacts with the linker histone H1 [19].

Regulatory relationships of His1:CG31617

• These results suggest that ASH2 maintains active transcription by binding a producer of nuclear phosphoinositides and downregulating histone H1 hyperphosphorylation [20].
• The Drosophila don juan (dj) gene encodes a basic protein that is expressed solely in the male germline and shows structural similarities to the linker histone H1 [21].

Other interactions of His1:CG31617

• We also show that histone H1 hyperphosphorylation is dramatically increased in both ash2 and sktl mutant polytene chromosomes [20].
• Our results argue against a proposal of a shared role of HMGD and histone H1 in Drosophila chromatin [22].
• Hence, the mechanism of transcriptional repression by p300 is distinct from that of histone H1, PARP-1 or Sir2 [23].
• Regular spacing of nucleosomes with or without histone H1 is sufficient to maximally repress transcription from hsp70 and fushi tarazu gene promoters [24].
• Moreover, we found that each of the individual core histones, but not histone H1 or high mobility group protein 1, bound to the knirps enhancer to give a repetitive DNase I footprint pattern with a periodicity of about 10 base pairs, which is approximately one turn of the DNA helix [25].

Analytical, diagnostic and therapeutic context of His1:CG31617

• Chromatin immunoprecipitation analysis confirmed that specific ribosomal proteins are associated with chromatin in a histone H1-dependent manner [5].
• In the present study, we have compared the condensation brought about by histone H1 of a SAR DNA fragment in the histone spacer region of Drosophila melanogaster with that of a random DNA (pBR322 EcoRI-SalI) fragment by circular dichroism spectroscopy [26].
• PCR cloning of a histone H1 gene from Anopheles stephensi mosquito cells: comparison of the protein sequence with histone H1-like, C-terminal extensions on mosquito ribosomal protein S6 [14].

References