Fig. 4.

Identification of RNA- and cell line-specific pre-miRNA-binding proteins using Csy4*-based RNA affinity purification. (A) In vitro-transcribed, Csy4 hairpin-tagged pre-let-7a, pre-miR-200a, and pre-miR-342 were used as bait for Csy4*-based affinity purification from HeLa and NT2 cell extracts. Equal amounts of purified samples were separated via 4–20% SDS/PAGE and visualized by silver staining. (B) Purified samples from A were separated by SDS/PAGE and probed for the presence of Lin28A, ATP-dependent RHA, and THUMP domain-containing protein 1 by Western blot analysis.