Two-step IP assays in whole-cell lysates of A549 cells transfected with FLAG-tagged PGC1α. First phase IPs were conducted with FLAG antibodies (left) and following elution with FLAG peptides, eluates were further subjected to second phase IPs with LRP130 antibodies (right). Samples were subjected to Western blotting and qPCR analysis for LRP130, PGC1α and GUARDIN, respectively. 