Figure 6.

Matching ATF6 Dynamics in Experiment and Model

(A) ATF6 mRNA expression after 8 or 24 h of exposure to a broad concentration range of tunicamycin in HepG2 WT cells using TempO-seq, represented as the mean of log2FC ± SE of three biological replicates.

(B) Western blot of uncleaved ATF6 (G, glycosylated, UG, unglycosylated) measured in HepG2 WT cells at 2, 4, 6, 8, 16, or 24 h after exposure to tunicamycin (6 μM) or DMSO. As protein loading control, tubulin protein expression was assessed.

(C) Quantified protein expression of the indicated ATF6 forms from three biological replicates after protein loading correction using tubulin (symbols and shaded area represents mean ± SE with the significance levels represented as **p_adj < 0.05, ***p_adj < 0.01). Cleaved ATF6 was estimated based on the difference between total uncleaved ATF6 at 4, 6, and 8 h versus the 2-h time point.

(D) Diagram of relation between different ATF6 forms during tunicamycin treatment, where ATF6_G and ATF6_UG represent glycosylated and unglycosylated forms, respectively.

(E) Model-predicted dynamics of free ATF6 and the downstream pATF6(N) upon exposure of tunicamycin at 1 and 6 μM.