Chromomycin A3 is an anthraquinone antibiotic and antitumor agent isolated from S. griseus that is used as a fluorescent probe for DNA with excitation/emission spectra of 445/575 nm.[1],[2] Its DNA binding is specific to two or more contiguous GC base pairs, which makes it suitable for characterizing heterochromatin in plants with species-specific AT:GC ratios.[2],[3] Chromomycin A3 is cytotoxic against non-small cell lung cancer and cervical cancer in vitro (IC50s = 1, 42, 60, and 40 nM for HCC44, A549, ME180, and HeLa cells, respectively).[4],[5] It also inhibits oxidative stress- and DNA damage-induced neuronal injury by enhancing Sp1 and Sp3 transcription factor binding.[6]
Reference:
[1]. Crissman, H.A., and Tobey, R.A. Methods in cell biology. 33, (1990).
[2]. Van Dyke, M.W., and Dercan, P.B. Chromomycin, mithramycin, and olivomycin binding sites on heterogeneous deoxyribonucleic acid. Footprinting with (methidiumpropyl-EDTA)iron(II). Biochemistry 22(10), 2373-2377 (1983).
[3]. Schwarzacher, T. Methods in molecular biology. 1370, (2016).
[5]. Miller, S.C., Huang, R., Sakamuru, S., et al. Identification of known drugs that act as inhibitors of NF-κB signaling and their mechanism of action. Biochem. Pharmacol. 79(9), 1272-1280 (2016).
[6]. Chatterjee, S., Zaman, K., Ryu, H., et al. 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. Ann. Neurol. 49(3), 345-354 (2001).