Figure 2

Immunoproteasomes in BV-2 microglia. BV-2 cells were subjected to 24 h IFNγ and prepared for gene expression (n = 6) and protein (n = 7) analysis. (a) Immunoproteasome genes are significantly increased following treatment (β5i: t(5.145) = −6.524, p = 0.001; β1i: t(5.024) = −6.795, p = 0.001; β2i: t(5.532) = −17.691, p < 0.001; pa28α: t(4.010) = −3.143, p = 0.035) accompanied by increased β5i protein levels (t(12) = −6.006, p < 0.001). (b) Gene expression analysis reveals that β5 (t(5.783) = 5.745, p = 0.001) is significantly decreased, however no other core subunits catalytic subunits are changed (β1:t(9) = −0.647, p = 0.534; β2:t(6.011) = −0.469, p = 0.656). Total protein levels of the β5 catalytic subunit is significantly reduced following treatment with IFNγ (t(4.637) = 4.129, p = 0.011). (c). Assembled immunoproteasomes are significantly increased (n = 4) following IFNγ treatment (t(3.543) = −4.452, p = 0.015). Assembled constitutive proteasomes are reduced (n = 4) after IFNγ treatment (t(6) = 5.675, p = 0.001). Data are presented as relative fold change compared to untreated control cells, analysed by independent samples t-test. (P-purified proteasome).