Disease relevance of Toyomycin

• Tailoring modification of deoxysugars during biosynthesis of the antitumour drug chromomycin A by Streptomyces griseus ssp. griseus [1].
• The effects of both chromomycin and TFO on transcription were studied by using an HIV-1 LTR-directed in vitro transcription system [2].
• Species specific differences in the toxicity of mithramycin, chromomycin A3, and olivomycin towards cultured mammalian cells [3].
• Furthermore, confirmation of experiments relating sensitivity to nick translation and positivity to CMA3 may allow an indirect in situ visualization of nicked and partially denatured DNA, which could correlate with certain forms of male factor infertility [4].
• Thick tissue slides (100 microm), stained for DNA with chromomycin A3, from 4 patients (with benign hyperplasia, prostatic intraepithelial neoplasia (PIN), and well-and poorly-differentiated adenocarcinoma of the prostate), were studied in order to test the practicability of the developed methodology [5].

High impact information on Toyomycin

• Dual-beam high-speed sorting has been developed to facilitate purification of chromosomes based on DNA staining with the fluorescent dyes Hoechst 33258 and chromomycin A3 [6].
• A similar hierarchy of accessible binding sites (naked DNA greater than chromosomes greater than chromatin) was also observed for the noncovalent interaction of chromomycin A3 or ethidium bromide with the human cell DNA [7].
• The in situ hybridization results obtained show that the H3 isochore family is localized in two coincident sets of bands of human metaphase chromosomes: telomeric bands and chromomycin A3-positive 4',6-diamidino-2-phenylindole-negative bands [8].
• The minor-groove DNA binding drug chromomycin A3 bound to the GC-rich flanking sequences and inhibited the association of Tax and the Tax-CBP complex without affecting CREB binding [9].
• Ploidy was assessed by microdensitometry of Chromomycin A3 fluorescence [10].

Chemical compound and disease context of Toyomycin

• The G-C ligand chromomycin A3 exhibited a different spectrum of cell toxicity and tyrosinase stimulation compared with Hoechst 33258 [11].
• Binding of distamycin and chromomycin to human immunodeficiency type 1 virus DNA: a non-radioactive automated footprinting study [12].
• Bacteriophage T4 DNA was detected and analyzed inside E. coli by dual-laser flow cytometry using a dye combination of Hoechst 33258 (H33258) and chromomycin A3 (CA3) which bind to A-T- and G-C-rich regions of DNA, respectively [13].
• Anoxia significantly reduced bleaching rates and changed the order of reaction of both propidium iodide (an intercalator) and chromomycin A3 (a minor-groove binder) bound to DNA; it afforded the greatest protection at low photon fluxes [14].
• The binding of chromomycin A3, an antitumour antibiotic, to various DNA and chromatin isolated from mouse and rat liver, mouse fibrosarcoma and Yoshida ascites sarcoma cells was studied spectrophotometrically at 29 degrees C in 10-2 M Tris-HCl buffer, pH 8.0, containing small amounts of MgCl2 (4.5-10-5--25-10-5 M) [15].

Biological context of Toyomycin

• Sequence-selective DNA binding drugs mithramycin A and chromomycin A3 are potent inhibitors of neuronal apoptosis induced by oxidative stress and DNA damage in cortical neurons [16].
• Here we demonstrate that mithramycin A and its structural analog chromomycin A3 are potent inhibitors of neuronal apoptosis induced by glutathione depletion-induced oxidative stress or the DNA-damaging agent camptothecin [16].
• We now show that 1 to 2 micrometer AcD or chromomycin A3, both of which intercalate at G-C base-pairs on DNA, selectively and completely block RnE processing [17].
• Photo-crosslinking in the presence of antibiotics distamycin and/or chromomycin suggested that interphase lamins interacted with both A-T-rich DNA and G-C-rich DNA; interactions with G-C-rich DNA predominated [18].
• For each step of the cell cycle, immunolabeled RPI molecules and DNA specifically stained with chromomycin A3 were simultaneously imaged at high resolution through numerous optical sections [19].

Anatomical context of Toyomycin

• Purified guinea pig megakaryocytes and platelets were incubated with WGA conjugated with rhodamine, cytocentrifuged, and then exposed to Chromomycin A3 for the assessment of ploidy [10].
• The measurement of chromomycin A3/DAPI fluorescence ratios is shown to allow base content determinations in eu- and heterochromatic regions of interphase cell nuclei [20].
• In the low-field spectrum of chromomycin A3 bound to calf thymus DNA, a small shoulder was observed on the upfield side of the G-C imino proton peak [21].
• For example, whereas the mouse cells were more resistant to mithramycin than CHO cells, the sensitivity pattern was reversed for both chromomycin A3 and olivomycin [3].
• Chromomycin A3 (250 mug/kg) suppressed the humoral immune response in rats against sheep erythrocytes when administered 48 h or later after antigenic stimulus [22].

Associations of Toyomycin with other chemical compounds

• The fluorescence emission of the DNA-Chromomycin complex was similar to that of fluorescein, and thus both rhodamine-WGA and Chromomycin A3 fluorescence could be analyzed in the same cell [10].
• Development of enzyme immunoassay for chromomycin A3 and olivomycin using beta-D-galactosidase as a label [23].
• The minor groove-binding drug chromomycin A3, but not distamycin A, disrupted Tax-enhanced CREB binding to the TxRE [24].
• The minor groove specific drugs chromomycin A3, distamycin A and actinomycin D competed against UBF for enhancer binding, suggesting that UBF, like other HMG-box proteins, probably interacts with the minor groove [25].
• Irrespective of their mode of interaction with DNA, such GC-specific antibiotics as actinomycin, echinomycin, mithramycin and chromomycin find new binding sites associated with DAP-containing sequences and are excluded from former canonical sites containing I.C base pairs [26].

Gene context of Toyomycin

• Interestingly, GC-rich DNA-binding protein inhibitors, mithramycin A and chromomycin A3, strongly suppressed TNF-alpha-induced fractalkine mRNA expression, possibly through inhibition of transcriptional activities by NF-kappaB and Sp1 [27].
• The minor groove binder chromomycin A3 inhibited EGR1 complex formation but resulted in a smaller increase of the TBP complex [28].
• Their potencies in inhibiting cell-free transcription and endogenous c-fos expression in NIH3T3 cells, however, were chromomycin > nogalamycin > Hoechst 33342 [29].
• The polymorphic Sp100-rs repeat cluster in chromosome band 1D of the house mouse, Mus musculus, makes up as much as 0.1-5% of the haploid genome. 'High-copy' versions of this long-range repeat cluster are cytogenetically apparent as DAPI-negative chromomycin-A3-positive homogeneously staining regions (HSRs) [30].
• Chromomycin A3 (CMA3) staining was used to determine protamine deficiency [31].

Analytical, diagnostic and therapeutic context of Toyomycin

• Chromosomes were isolated from primary cultures 2-5 wk after amniocentesis, stained with Hoechst 33258 and chromomycin A3, and analyzed using dual beam flow cytometry [32].
• Molecular interactions between chromomycin, the Sp1 TFO and target DNA sequences were studied by gel retardation, triplex affinity capture using streptavidin-coated magnetic beads and biosensor technology [2].
• This is achieved by fluorescent in situ hybridization of biotinylated total human DNA, followed by high resolution fluorescence banding with the chromomycin/distamycin/DAPI triple stain [33].
• The nucleolar constrictions of the nucleolus organizer regions (NORs) displayed the brightest mithramycin- and chromomycin A3-fluorescence in the karyotypes and interphase nuclei of all species examined [34].
• We present titrations of the human delta beta-globin gene region with DNA minor groove binders netropsin, bisnetropsin, distamycin, chromomycin and four bis-quaternary ammonium compounds in the presence of calf thymus topoisomerase II and DNase I [35].

References