Ring-Structured DNA and RNA as Key Players<i>In Vivo</i>and<i>In Vitro</i>

Ring-structured DNA and RNA exhibit a variety of unique features in chemistry, biology, medicine, material science, so on, which cannot be accomplished by their non-cyclic counterparts. In this review, both naturally occurring DNA/RNA rings artificially synthesized ones have been comprehensively covered, mainly to bridge these two growing fields. the first part, structures functions (extrachromosomal circular DNA, circulating cell-free DNAs, cyclic RNAs, others) are described. Their roles as biomarkers for disease diagnosis especially noteworthy. The second part presents recent methods synthesize selectively efficiently from oligonucleotide fragments. desired sequences sizes successfully prepared large amounts versatile applications. Production cells using autocatalytic transcripts is also Lastly, practical applications briefly reviewed. Critical significance cooperation areas further developments, well strong potential interdisciplinary studies, emphasized. sciences on rapidly growing, highly promising future