Identification of long noncoding RNA DANCR binding proteins

To capture endogenous DANCR transcripts, we designed and synthesized 11 5′ biotinylated 90-mer DNA oligonucleotides antisense that spanned the entire length of the target RNA DANCR. Pull-down proteins were separated by SDS-PAGE gel and stained with Fast Silver Stain Kit (Beyotime, China). Cell lysates were incubated with biotinylated DNA probes (10 pmol) and 50 μL of streptavidin-agarose beads (Invitrogen) for 1 hour. The proteins were precipitated and diluted in 50 μl of digestion buffer (8 M urea, 50 mM Tris-HCl pH 7.8), separated by SDS-PAGE gel electrophoresis and visualized by silver staining using the PAGE Gel Silver Staining Kit (Solarbio, Beijing, China) as the protocol described. Specific bands were excised for proteomics screening by mass spectrometry analysis (Tianjin Novogene Bioinformatic Technology, Tianjin, China).