Table 1.
Summary of photocrosslinking experiments
| Ribozyme nt | XL Agent | Target | Other XL | Metal | Activity |
|---|---|---|---|---|---|
| none | G21/U421 | Mg++ | − | ||
| A-1/G8 | Co(NH3)63+ | + | |||
| U+2/G36 | Co(NH3)63+ | + | |||
| G8 | 6-thio-dG8 | A-1 | Mg++ | − | |
| G+1 | Co(NH3)63+ | − | |||
| A26 | DiAP26 | Mg++ | N/D | ||
| Co(NH3)63+ | N/D | ||||
| G36 | 6-thio-dG36 | Mg++ | N/D | ||
| U+2 | Co(NH3)63+ | + | |||
| U37 | 4-thio-U37 | Mg++ | N/D | ||
| U+2 | Co(NH3)63+ | − | |||
| U+2/G36 | Co(NH3)63+ | + | |||
| A38 | 2-AP382 | Mg++ | N/D | ||
| G+1 | Co(NH3)63+ | + | |||
| Substrate nt | |||||
| G+1 | 6-thio-dG+1 | G6 | Mg++ | − | |
| G21/U42 | Mg++ | − | |||
| U+23/G8 | Co(NH3)63+ | − | |||
| C+3/G36 | Co(NH3)63+ | − | |||
| G21/A43 | Co(NH3)63+ | − | |||
| U+2 | 4-thio-U+2 | A9 | Mg++ | − | |
| G8 | Co(NH3)63+ | − | |||
| G36 | Co(NH3)63+ | − | |||
| C+3 | 4-thio-U+3 | A9 | Mg++ | − | |
| G8 | Co(NH3)63+ | + | |||
| RLB4 | Co(NH3)63+ | + | |||
| U+2/G36 | Co(NH3)63+ | + |
1
Obtained at 254 nm.
2
Chan, P. and Burke, J.M. unpublished results.
3
Impossible to determine clearly which substrate residue was mapped since deoxyG+1 does not give a band after T1 or alkali digestion. The cut off appeared to be a mixture of U+2 and C+3.
4
We were unable to identify unambiguously the residue involved in this crosslink although it is reproducible.