The catalytic center of the 359-base, negative strand of the satellite RNA (q.v.) of the tobacco ringspot virus; it consists of a catalytic segment 50 bases long and a 14-base substrate. The catalytic RNA forms a closed loop during the cleavage reaction, hence the term hairpin ribozyme (HR). The HR has been engineered to bind to and cleave specific foreign RNAs. One of these is the transcript from a gene of the HIV-I virus that is essential for its replication. Suitably engineered ribozymes may someday play an important role in AIDS therapy. See AIDS, HIV, plus (+) and minus (−) viral strands, ribozyme.
Subjects: Genetics and Genomics.