Team:University College London/Protocols/T4dnaligase


1. Set up the following reaction in a microcentrifuge tube on ice. (T4 DNA Ligase should be added last. Note that the table shows a ligation using a molar ratio of 1:3 vector to insert.)

10X T4 DNA Ligase Buffer 2 μl
Vector DNA (3 kb) 50 ng (0.025 pmol)
Insert DNA (1 kb 50 ng (0.076 pmol)
Nuclease-free water to 20 μl
T4 DNA Ligase 1 μl

2. The T4 DNA Ligase Buffer should be thawed and resuspended at room temperature.

3. Gently mix the reaction by pipetting up and down and microfuge briefly.

4. For cohesive (sticky) ends, incubate at 16°C overnight or room temperature for 10 minutes.

5. For blunt ends or single base overhangs, incubate at 16°C overnight or room temperature for 2 hours (alternatively, high concentration T4 DNA Ligase can be used in a 10 minute ligation).

6. Chill on ice and transform 1-5 μl of the reaction into 50 μl competent cells.