Development of Arabidopsis Protein Chip
Protocols


LIC Cloning Procedure of PCR Fragments

Each ORF was amplified using gene-specific primers containing LIC-compatible extensions, either from cDNA collections or from genomic DNA. The primers were designed using the sequence information in the TAIR and MATDB databases, as follows: the first 25-26 nucleotides of the ORF including the ATG start codon were included in the Forward primers sequence; the last 25-26 nucleotides excluding the STOP codon were included in the Reverse primers. The LIC-F (5’ GCACAAGAAGGTCC 3’) and LIC-R (5’ GAAGAAGAGAGGTGC 3’) sequences were added at the 5’ ends of the corresponding primers. The primers were synthesized and stored lyophilized by MGW in 96-well plate format. Before use, 100 pM/µl stock solutions were made by re-suspending the lyophilized primers in double-distilled water and stored at -20ºC.

For ORF amplification, PCR reaction mixture contained 2.5 U Pfx (Invitrogen) DNA polymerase, 0.2 mM dNTPs, and 100 ng of genomic DNA or purified plasmid DNA in 50 µL reactions. The following cycling conditions were used: (1) 95°C for 2 min, 5 cycles of 95°C for 30 sec, 54°C for 30 sec, 72°C for 6.5 min, 28 cycles of 95°C for 30 sec, 62°C for 30 sec, and 72°C for 6.5 min, followed by 10 min at 72°C; (2) 95°C for 2 min, 5 cycles of 95°C for 30 sec, 62°C (-4°C/cycle) for 1 min, 72°C for ):8 min, 5 cycles of 95°C for 30 sec, 47°C (+4°C/cycle), 72°C for 8 min, 27 cycles of 95°C for 30 sec, 57°C for 1 min, and 72°C for 8 min, followed by 10 min at 72°C. (3) 95°C for 2 min, 30 cycles of 95°C for 30 sec, 54°C for 30 sec, 68°C for 2 to 3.5 min, and 68°C for 10 min.

PCR products of the correct size, visualized with ethidium bromide under UV illumination, were either excised from 1% agarose-TAE gels and gel-purified (Qiaquick 96 Gel Extraction kit, Qiagen) or cleaned using Qiaquick 96 PCR purification kit (Quiagen).

For LIC cloning, purified PCR products (50-100 ng) were treated with T4 DNA polymerase in the presence of 25 mM dATP for 30 min at 22°C, in 96-well PCR plates in the total volume of 5 µl. The StuI linearized and gel-purified pLIC-C-TAP (50-100 ng) vector was similarly treated with T4 DNA polymerase in the presence of 25 mM dTTP. T4 DNA polymerase in the total volume of 5µl; enzyme was inactivated by heating the reactions at 75°C for 20 min. Equal volumes of treated PCR fragments and linearized vector were mixed, heated 2 min at 65°C and let cool down to 22°C for 10 min. 10 µl volume mixtures were transformed into in-house prepared competent DH10B E.coli using the heat-shock protocol adjusted for 96-well plates. Transformed bacteria were plated on selection LB medium containing 50 µg/ml spectinomycin and incubated over-night at 37°C.

Cloning Reactions

PCR Product Vector
PCR Product 5uL (~50ng) Cut Vector* 2uL(~50ng)
10X Buffer 2 1uL 10X Buffer 2 1uL
25mM dATP 2uL 25mM dTTP 2uL
100mM DTT 0.5uL 100mM DTT 0.5uL
T4 DNA Polymerase 0.2uL T4 DNA Polymerase 0.2uL
Water 1.3uL Water 4.3uL
Total 10uL Total 10uL


Cloning Steps

Incubate at 22°C for 30 minutes
Incubate at 75°C for 20 minutes
Cool for 2-3 minutes

Mix
10uL PCR Product Reaction
10uL Vector Reaction

Incubate at 65°C for 2 minutes
Incubate at 22°C for 10 minutes

Transform into E. coli DH10B cells

*NOTE: Cut pLIC-C-TAP with Stu1 Enzyme