Design principles for the glycoprotein quality control pathway
Fig 6
Robustness of quality control cycle to changing production rates.
(A) The folding fraction achieved with fixed rate constants is plotted as a fraction of the maximum achievable folding fraction fmax for Punfolded = 1 as the protein production rate kpt is varied. Fixed rate constants kc, kg, k-g, and kd are those that achieve fmax with mf = 0.001 at various protein production levels: kpt = 0.1 (red curves and star), kpt = 1 (green), and kpt = 10 (blue). (B) The Punfolded corresponding to the folding fractions in (A). (C) Analogous plot to (A), with rate constants fixed at the optimal values for specific kpt values, except that the degradation rate constant kd adjusts to maintain Punfolded = 1. If kd adjustment cannot achieve Punfolded = 1, then kd adjustment minimizes the difference from Punfolded = 1. (D) The Punfolded corresponding to the folding fractions in (C).