Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.
1. The structure formed by a polynucleic acid by base-pairing between neighboring complementary sequences of a single strand of either DNA or RNA.
2. The structure seen in a prostaglandin where two segments of the molecule fold back on one another.
hairpina double-stranded structure found in single-stranded NUCLEIC ACID molecules, due to BASE PAIRING between adjacent complementary sequences. The two sequences are inversely arranged and may be directly adjacent, as in a PALINDROME, or interrupted by a non-complementary sequence. In the former case a double-stranded segment (hairpin) is generated; in the latter a hairpin-loop structure forms.
a secondary structure that occurs in single-strand RNA during protein synthesis in which the strand turns back on itself. The structure is the result of base pairing and hydrogen bond formation.