Table 2.
G-Quadruplex DNA Substrates Used for In Vitro Helicase Studiesa
| G-Quadruplex DNA | Structure | Details | Nucleotide Sequence (5′–3′)b |
|---|---|---|---|
| 3′-Tail d(CGG)7-G4 |  |
- Fragile X syndrome CGG repeats - For helicases that require 3′ tail to load, (e.g. BLM, WRN) |
3′-Tail d(CGG)7: CGGCGGCGGCGGCGGCGGCGGCGTGGA CTG |
| 5′-Tail d(CGG)7-G4 |  |
- Fragile X syndrome CGG repeats - For helicases that require 5′ tail to load, (e.g. FANCJ) |
5′-Tail d(CGG)7: GTCAGGTGCGGCGGCGGCGGCGGCGGCGGC |
| TP-G4 |  |
- A consensus repeat from murine immunoglobulin heavy chain switch region - Both ends contains tails, 5′-21 nt tail; 3′-7 nt tail |
TP: TGGACCAGACCTAGCAGCTATGGGGGAGCTGGGGAAGGTGGGAATGTGA |
| rD4-G4 |  |
- A sequence from human 28 S ribosomal RNA gene (acc. No. M11167) - Both ends contains tails, 5′-10 nt tail; 3′-25 nt tail |
rD4: TTGAAAATCCGGGGGAGAGGGTGTAAATCTCGCGCCGCGCCGTACC |
| Z33-G4 |  |
- A complementary sequence to bases 159–191 of the supF gene in plasmid pZ189 - Both ends contain 14 nt tails |
Z33: AAAGTGATGGTGGTGGGGGAAGGATTTCGAACC |
| 5′-15ntTeR2-G4 |  |
- Human telomere sequence - 5′ end contain 15 nt tail |
5′-15ntTeR2: TCATGACTAGACATGTTAGGGTTAGGGTTA |
a
See text for details.
b
The guanine residues that compose the G-quartet structures in oligonucleotides are underlined.