The average level of URE3-BP protein was defined as being 100% in the GFP shRNA control transfectants. The levels of URE3-BP and the actin standard were quantified from Western blotting. Values are expressed as the percentage of URE3-BP protein or mRNA of the GFP control shRNA transfectant level ± SE, with the P-value following each. There were three biological replicates for all samples, each run in triplicate plus serial dilutions (1:2, 1:4, and 1:8), except for HM1:IMSS nontransfectants, which had one biological replicate run in triplicate plus serial dilutions. All samples were normalized to actin, and compared to the GFP control using Student's t test. URE3-BP protein levels are not statistically different between the URE3-BP (350–378) and (580–608) samples (two-tailed Student's t test for comparing two sample averages, P = 0.3262) or between the GFP and HM1:IMSS nontransfected samples (two-tailed Student's t test for comparing two sample averages, P = 0.2346). A representative Western blot is shown in Figure 3.