Seminár z kvalitatívnej teórie diferenciálnych rovníc

Seminar on Qualitative Theory of Differential Equations

Štvrtok 17.10.2019 o 14:00, poslucháreň M-223

Pavol Bokes (KAMŠ FMFI UK):

Piecewise deterministic modelling of stochastic protein production with feedback in burst size

Abstract:

Burst-like synthesis of protein is a significant source of cell-to-cell variability in protein levels.

Negative feedback is a common example of a regulatory mechanism by which such stochasticity

can be controlled. Here we consider a specific kind of negative feedback, which makes bursts

smaller in the excess of protein. Increasing the strength of the feedback may lead to dramatically

different outcomes depending on a key parameter, the noise load, which is defined

as the squared coefficient of variation the protein exhibits in the absence of feedback.

Combining stochastic simulation with asymptotic analysis, we identify a critical value of noise load:

for noise loads smaller than critical, the coefficient of variation remains bounded with increasing

feedback strength; contrastingly, if the noise load is larger than critical, the coefficient of variation

diverges to infinity in the limit of ever greater feedback strengths. Interestingly, feedbacks

with lower cooperativities have higher critical noise loads, suggesting that they can be preferable

for controlling noisy proteins.

This is a joint work with Yen Ting Lin and Abhyudai Singh.