GSM6697777: in vitro-transcribed tRNA Asn; Schizosaccharomyces pombe; RNA-Seq
The pJET1 vector carrying the tRNA-Asp and tRNA-Asn sequence, respectively, was linearized with NcoI, and 2.5 µg of the linear vector was used for in vitro transcription using the TranscriptAid T7 High Yield Transcription Kit (ThermoFisher) according to the manufacturer's instructions. Following an 8 hour incubation at 37 °C with nucleotides and the T7 RNA polymerase and subsequent DNase I treatment, the respective tRNA was purified from the reaction using phenol/chloroform extraction followed by gel filtration with Sephadex G50 (GE Healthcare).  Extraction of the RNA was performed as described in the "SAMPLEs" section. 500 ng RNA was hybridized to 500 nM of the respective stemloop-primer with the following thermocycling program: 95 °C for 2 min, 65 °C for 30 sec, ramp down to 4 °C with 5 °C/30 sec. After hybridization and incubation on ice for 1 min, 100 µM of each dNTP and 100 nM RT-KTq I614 DNA polymerase were added. The reverse transcription was carried out in reaction buffer (50 mM Tris-HCl (pH 9.2), 16 mM (NH4)2SO4, 25 mM MgCl2, 0.1% Tween 20) in a total volume of 20 µL. For experiments using decreased dCTP concentrations, 25 µM, 12.5 µM and 6.25 µM dCTP were added to the RT reaction. Following incubation at 55 °C for 1 h and incubation on ice for 10 min, the cDNA was amplified using Taq polymerase. Amplification was performed with 5 µL cDNA in reaction buffer containing 2.5 µM dNTPs, 2 mM MgCl2, 1 x Taq buffer+ KCl and 1.25 U Taq polymerase (Thermo Fisher) in a total volume of 200 µL. Primers binding at the 3' end contained a barcoded sequence for multiplexing the PCR products. Samples were separated on a 2% agarose gel, and the respective PCR products were gel-purified using the QIAquick Gel Extraktion Kit (Qiagen) according to the manufacturer's protocol. Library preparation of amplified tRNAs for deep sequencing was performed using the NEXTflexR qRNA-SeqTM Kit v2 – Set C (Bioo Scientific) according to the manufacturer's protocols.