MiR-93 and miR-155 can repress endogenous AID. (A) Representative western demonstrating that transient transfection of pAL-93, pAL-155 and shAID expression constructs repress endogenous AID protein levels in MCF-7 cells. ShAID produces an AID-targeting siRNA from a pAL-driven hairpin expression vector as in 2A. Ctl, pAL-1 transfected; PCNA, Proliferating Cell Nuclear Antigen load control. (B) Relative AID mRNA levels corresponding to replicate transfections performed as in A (n = 3) as determined by quantitative PCR.