Design principles for the glycoprotein quality control pathway
Fig 2
Quality control engenders a trade-off between folding accuracy, speed, and energy.
(A) Shaded regions in the phase diagram represent all combinations of folding fraction f and total steady-state unfolded protein Punfolded that can be achieved by varying cycle parameters kc, k-c, kr, k-r, kg, k-g, and kd while keeping a fixed folding rate kf, production rate kpt, misfolded fraction mf, and background protein concentration Pb. Solid lines represent the maximal achievable folding fraction fmax. Dots represent the efficiency metric . (B) Each curve adjusts kc, k-c, kr, k-r, kg, k-g, and kd to maximize the folding fraction (Eq 2) while the total cycle energy (Eq 3) is varied and the total unfolded protein
is constrained to equal one. Each curve shows a distinct level of background proteins Pb, with fixed kpt = 0.1, kf = 0.1, and mf = 0.001 for all curves.