The vector pTR-UF3 was digested with pTR-UF3 using AscI and PacI for 5 hours according to the following protocol:
- 10 µg vector
- 2 µL AscI
- 2 µL PacI
- 5 µL 10X BSA
- 5 µL 10X buffer 4
- Up to 50 µL nuclease-free water
21/09/2010
The digested capsid fragments and the vector were loaded on a 1% agarose gel and ran for 50 minutes. The ~2.2 KB (capsid genes) and ~5 KB (vector) fragments were then purified from the gel.
A ligation reaction was carried out according to the following protocol:
- ~3.556 µg insert (Capsid genes)
- ~2.667 µg vector
- 6 µL T4 DNA ligase
- 8 µL T4 DNA ligase buffer
- Up to 80 µL nuclease-free water
- Incubate at 16 ͦC overnight
22/09/2010
The ligation product from the day before was used to transform electrocompetent cells (Invitrogen), according to the following:
- 600 µL of electrocompetent bacteria were mixed with 62.5 µL DNA from the ligation reaction (about 125 ng per 20 µL bacteria), 20 µL of the mixture were placed in the electoporation cuvette
- Electroporation conditions:
- Recovery of bacteria was done by adding 1 mL LB media to each 20 µL of bacteria that were electroporated. The bacteria were collected in a 200 mL flask and incubated at 37ͦC with shaking at 225 rpm for 1 hour.
The bacteria were then used to inoculate 15 cm petri dishes with ampicillin resistance media. 500 µL were spread on each plate, and 50 plates in total were inoculated. The plates were incubated at 37 ͦC overnight.
23/09/2010
The plates from the previous day were collected, and 50 colonies were picked and used to inoculate miniprep cultures.
The colonies from the 50 plates were pooled together and cultured in 700 mL LB for 3 hours, after which a Megaprep (Invitrogen) was done (according to manufacturer's recommendations) to extract the plasmids that contain the shuffled capsid genes and create a library of those shuffled capsids that would be used for the selection of the best capsids, and thus best AAVs.
A left-over from the transormation from previous day was stored in the fridge and used to inoculate three more 15 cm plates, since the other 50 plates were not suitable for counting the colonies (very crowded!) to estimate the size of the library.
24/09/2010
5 flasks (?) of HEK cells were transfected with a total of 75 µg of the library DNA and AAV helper plasmid (1:1) for AAV production, using HBSS. However, the transfection was not successful.