Project description:Cells were washed with cold PBS twice and scraped from the plates, then centrifuged at 1000 rpm for 5 min to pellet cells. Washed cells were lysed with 400 L of cell lysis buffer (10 mM Tris-HCl pH7.5, 150 mM NaCl, 0.15% NP-40 and proteinase inhibitor cocktail) and incubated on ice for 10 min. The suspension was carefully add at the top of sucrose buffer (10 mM Tris-HCl pH7.5, 150 mM NaCl, 24% sucrose), and centrifuged at 3200g for 10 min to collect nuclear pellets. Pellets were resuspended in 250 L of Glycerol buffer (20 mM Tris-HCl pH7.5, 75 mM NaCl, 0.5 mM EDTA pH8.0, 50% glycerol), then then immediately add 250 μl Nuclear lysis buffer (10 mM Tris-HCl pH7.5, 300 mM NaCl, 7.5 mM MgCl2, 0.2 mM EDTA pH8.0, 1% NP-40, 1M urea). Mix by vortexing for 4 s and incubate on ice for 2 min. Centrifuge the lysate at 13,000 × g for 2 min to precipitate the chromatin–RNA complex. Briefly rinse the chromatin pellets with PBS-EDTA. RNA was extracted with Trizol reagent. RNA libraries were prepared according to manual of SMARTer smRNA-Seq Kit for Illumina (Clontech, 635031).
Project description:The newly discovered dynamic N6-methyladenosine (m6A) modification plays a critical role in gene expression from a post-transcriptional level. we profiled the transcriptome-wide m6A modification in mRNAs and lncRNAs in non-targeting control A375 cells(NC) and METTL3 knockdown A375 cells(shMETTL3). Methylated RNA immunoprecipitation sequencing results revealed that the RNA m6A modification is conserved. METTL3 knockdown altered the expression of RNAs m6A modified sites in A375 cells. Finally, we show that the transcriptome-wide m6A alterations occurring in mRNAs and lncRNAs following METTL3 knockdown suggest this process plays important regulatory roles during A375 growth. This study provides a framework for applying the m6A modification regulated by METTL3 to melanoma research.
Project description:We performed the transcripome-wild m6A-sequencing to compare the m6A profiles of negative control (NC) HeLa cells and ALKBH5 KO HeLa cells stably re-expressing wild type ALKBH5 (WT) or its mutant K235R (K235R)
Project description:To investigate the effect of HSATIII lncRNA on m6A modification, we performed m6A-RIP(RNA immuno precipitation) RNA-seq from heat shock-exposed HeLa cells upon HSATIII knockdown.
Project description:We report the application of MeRIP-seq to map m6A peaks in wild type and METTL5 KO HeLa cells to investigate targets of the m6A methyltransferase METTL5.
Project description:The chromatin fraction was isolated from 5x107 HeLa cells. Chromatin was digested in 100 mL of MNase (40 units/ mL ) reaction buffer for 3 min at 37 °C in a thermomixer (1,400 rpm). After addition of 10 L EGTA (25mM) to inactivate MNase, soluble digested chromatin was collected by 13,000 rpm centrifuge for 5 min. 10 mg of Pol II antibody was conjugated to magnetic protein A beads. The supernatant was diluted with 400 mL of NET-2 buffer and pSer2-Pol II antibody-conjugated beads were added. Incubated the IP reaction at 4 °C for 1 hr. The beads were washed with 1 mL of NET-2 buffer six times and 100 mL of 1xPNKT (1xPNK buffer and 0.05% Triton X-100) buffer once. Washed beads were incubated in 50 mL PNK reaction mix (1xPNKT, 1 mM ATP and 0.05 U/ml T4 PNK (NEB)) in Thermomixer at 37 °C, 1,400 rpm for 6 min. Beads were washed with 1 mL of NET-2 buffer once and RNA was extracted with Trizol reagent. RNA was suspended in urea Dye (7M Urea, 1xTBE, 0.1% BPB and 0.1% XC) and resolved on 6% TBU gel (Invitrogen) at 200 V for 5 min. Gels with 30-160 nt RNAs were collected. 0.2 mL tube was prepared with holes made with 25G needle and placed in a 1.5 mL tube. Gel fragments were placed in the layered tube and broken down by centrifugation at 12,000 rpm for 1 min. The small RNAs were eluted from gel using RNA elution buffer (1 M NaOAc and 1 mM EDTA) at 25 °C for 1 hr in Thermomixer (900 rpm). Eluted RNA was purified with SpinX column (Coster) with 2 glass filters (Millipore) and the flow-through RNA was ethanol precipitated.