DNA sugar-phosphate backbone

The DNA sugar-phosphate backbone is the structural framework of the deoxyribonucleic acid double helix, consisting of alternating sugar (deoxyribose) and phosphate groups joined by covalent phosphodiester bonds (National Human Genome Research Institute, 2024). This backbone provides the necessary stability for genetic information storage and serves as the scaffold for the nitrogenous bases that encode the genome (Nature Education, 2014). In a therapeutic context, the backbone is a critical target for several classes of anti-cancer agents and radiation therapies. For example, the drug bleomycin acts by abstracting a hydrogen atom from the C4 position of the deoxyribose sugar, leading to oxidative cleavage of the backbone and subsequent double-strand breaks (PubMed, 2021). Furthermore, while many alkylating agents primarily target nitrogenous bases, they can also form covalent adducts with the phosphate groups, and the resulting structural distortions often lead to backbone fragmentation during cellular repair attempts (StatPearls, 2023). Disrupting the integrity of the DNA backbone is a primary mechanism for inducing apoptosis in malignant cells, though it also contributes to the significant side effects associated with non-specific DNA-damaging therapies.

Other names

DNA backbonePhosphodiester backboneDeoxyribose-phosphate backbone

Induction of DNA strand breaks through oxidative damage to the deoxyribose sugar or alkylation of phosphate groups, leading to the collapse of the double helix structure and inhibition of DNA synthesis.