Identification and characterization of Prp45p and Prp46p, essential pre-mRNA splicing factors

Prp45p coprecipitates with Prp46p in vitro. (A) ³⁵S-methionine-labeled full-length Prp45p or fragments of the regions indicated were produced in vitro. (B) The in vitro -produced polypeptides were incubated with ATP-depleted yeast splicing extract containing HA₂-tagged Prp46p and with anti-HA antibodies on ice for 1 h before adding protein A-Sepharose beads. The pellets and supernates (1.6%) were analyzed by SDS-PAGE and the ³⁵S-labeled Prp45 polypeptides were visualized by autoradiography.