Dynamic changes in Mcl-1 expression regulate macrophage viability or commitment to apoptosis during bacterial clearance
J. Clin. Invest. Helen M. Marriott, et al. 115:359 doi:10.1172/JCI21766 [Go to this article.]

Figure 3
Pneumococcal infection of macrophages results in increased expression of a proapoptotic Mcl-1 isoform. (A) Western blot of total protein from MDMs at the indicated time points after infection with pneumococci, probed with anti–Mcl-1 and anti-actin antibodies showing the appearance of the band of approximately 34 kDa. The donor is representative of 1 of the series in Figure 1C. The mean levels of nuclear apoptosis at each time point for this donor are indicated. (B) Western blot of total protein from U937 cells or MDMs (3 donors in 3 separate experiments) 20 hours after infection with pneumococci or mock infection and U937 cells transfected with Mcl-1_Exon-1 or empty vector probed with anti–Mcl-1 antibody, with in vitro translation of Mcl-1, Mcl-1S/°TM, and Mcl-1_Exon-1 as standards. (C) Genomic organization of Mcl-1 and Mcl-1_Exon-1. The filled regions represent the coding region of the 2 transcripts. (D) Percentage of nonviable infected or mock-infected U937 cells 16 hours after nucleofection with vectors containing full-length Mcl-1, Mcl-1_Exon-1, Bax, or empty vector. Results represent the analysis of 3 separate experiments. P < 0.05, Spn– Mcl-1 vs. Spn– Mcl-1_Exon-1; P < 0.05, Spn+ Mcl-1 vs. Spn+ Mcl-1_Exon-1; Student’s paired t test. (E) Percentage of EGFP-positive cells demonstrating features of apoptosis after DAPI staining in the same experiments as in D. P < 0.05, Spn– Mcl-1 vs. Spn– Mcl-1_Exon-1; P < 0.05, Spn+ Mcl-1 vs. Spn+ Mcl-1_Exon-1; P < 0.05, Spn+ empty vector vs. Spn+ Mcl-1; Student’s paired t test.