GC-rich double-stranded DNA (GC-rich dsDNA)

GC-rich double-stranded DNA consists of genomic regions with a high proportion of guanine and cytosine base pairs, which are characterized by three hydrogen bonds, providing greater structural stability than AT-rich regions [1]. These sequences are predominantly located within gene promoter regions and CpG islands, where they serve as critical docking sites for transcription factors and the transcriptional machinery [2]. In various pathologies, particularly oncology, the dysregulation of genes controlled by GC-rich promoters drives tumor progression and chemoresistance [3]. Therapeutic agents such as Dactinomycin and Mithramycin A exploit the unique structural and electronic properties of these regions to bind via intercalation or minor groove occupancy, thereby inhibiting transcription and DNA replication [4, 5]. While effective, the lack of absolute sequence specificity often leads to significant side effects, including myelosuppression and gastrointestinal toxicity, due to the disruption of essential genes in healthy tissues [5]. Modern drug design aims to enhance the selectivity of these DNA-binding agents to better differentiate between pathological and physiological GC-rich sites [6]. Sources: [1] PubMed PMID: 15522860; [2] Nature Reviews Molecular Cell Biology; [3] Journal of Biological Chemistry; [4] PubChem (NIH); [5] StatPearls (Dactinomycin); [6] Nucleic Acids Research.

Other names

Guanine-cytosine rich DNAGC-rich sequencesGC-rich regionsCpG-rich DNA

Drugs targeting GC-rich double-stranded DNA typically act through intercalation between G-C base pairs or binding within the minor groove, which sterically hinders the binding of transcription factors and RNA polymerase, thereby inhibiting gene transcription and DNA replication [1, 4].