Chemical Labeling Achieves 8-Oxo-7,8-dihydroguanine Mapping in the Microrna Transcriptome.

A labeling chemistry-based methodology, APSC-8-oxoGua-seq, is developed to sequence 8-oxoGua in the microRNA transcriptome. N-(3-Azidopropyl)-spermine-5-carboxamide (APSC) is designed for the selective labeling of 8-oxoGua, where its azide facilitates the conjugation of a cleavable linker via the click reaction, achieving 8-oxoGua pull-down and sequencing. Using APSC-8-oxoGua-seq, 8-oxoGua can be identified at single-base resolution.