Duplex DNA guanine N2 (minor groove) (DNA-G-N2)

Duplex DNA guanine N2 in the minor groove is a specific nucleophilic site within the DNA double helix that serves as a critical target for certain tetrahydroisoquinoline alkaloids, such as trabectedin and lurbinectedin (Pommier et al., 2014, Nature Reviews Cancer). While many DNA-damaging agents target the major groove or the N7 position of guanine, these specific drugs form a covalent adduct with the N2 amino group of guanine located in the minor groove (D'Incalci & Galmarini, 2010, Molecular Cancer Therapeutics). This interaction causes the DNA to bend toward the major groove, a structural distortion that is recognized by the nucleotide excision repair (NER) machinery. Instead of being repaired, the drug-DNA complex traps the repair proteins, particularly those involved in transcription-coupled NER, leading to the formation of double-strand breaks and the induction of apoptosis (Marco & Gago, 2005, Current Medicinal Chemistry). This target is clinically significant in oncology, particularly for treating soft tissue sarcomas and small cell lung cancer, where the therapeutic window is influenced by the tumor's specific DNA repair deficiencies (Soares et al., 2007, BMC Cancer).

Other names

Guanine N2 amino groupDNA minor groove guanine N2Minor groove guanine N2 adduct siteN2-guanine DNA adduct site

Covalent binding to the N2 position of guanine in the minor groove of DNA, inducing a structural bend toward the major groove and interfering with transcription-coupled nucleotide excision repair (TC-NER) and transcription factor binding.