Does Triple Stranded DNA exist?
Triple-stranded DNA (also known as H-DNA or Triplex-DNA) is a DNA structure in which three oligonucleotides wind around each other and form a triple helix.
Can you have a triple helix?
As with a single helix, a triple helix may be characterized by its pitch, diameter, and handedness. Examples of triple helices include triplex DNA, triplex RNA, the collagen helix, and collagen-like proteins.
What causes triplex DNA structure?
A DNA triplex is formed when pyrimidine or purine bases occupy the major groove of the DNA double Helix forming Hoogsteen pairs with purines of the Watson-Crick basepairs. Intermolecular triplexes are formed between triplex forming oligonucleotides (TFO) and target sequences on duplex DNA.
What is triple helical structure?
A triple helix is formed after the binding of a third strand to the major groove of a duplex DNA through Hoogsteen base pairing. Pyrimidine-rich and purine-rich sequences can form stable triplex structures as a consequence of the formation of A–T–A and C+–G–C triplets (Fig.
What would a triple helix do?
These structures can induce transcriptional repression and site-specific mutagenesis or recombination. Triplex-forming oligonucleotides (TFOs) can bind to duplex DNA in a sequence specific fashion with high affinity, and can be used to direct DNA-modifying agents to selected sequences.
Does triple helical DNA exist in nature?
A well-established multi-stranded DNA structure, triple helical DNA (triplex DNA), both naturally occurring intramolecular H-DNA structures, and triplex-forming oligonucleotide (TFO)-targeted intermolecular triplexes will be the focus of this review.
What does DNA tell about a person?
These tests analyze a sample of a person’s DNA and look for specific changes associated with different conditions. Often, test results can help doctors diagnose and predict a person’s risk for developing a disease. Other DNA tests can tell people about whether they’re predisposed to certain traits.