Dynamics and information transmission in cell signaling

SILVINA PONCE DAWSON

Workshop; Spring College on Complex Systems; 2023

Cells continuously sense their environment and respond accordingly. On many occasions, these responses involve changes in gene expression. To modulate this expression, stimulus strengths can be encoded in the amplitude or the frequency of Transcription Factor (TF) nuclear fractions. In this talk I will make a brief introduction on information theory and of its applications in biology. I will then show some of the results we have obtained about the information transmission capabilities of frequency and amplitude modulation in gene expression. In particular, I will discuss to which extent these two modes can be used to multiplex the signaling capabilities of a single TF. In that regard, I will show that promoters can be found which are selectively activated by TF pulses but that this selectivity does not seem to exist for the prolonged nuclear TF accumulation that characterizes amplitude modulation. These results that we derive from modeling agree with experimental observations and can explain why promoters are not optimized for one of the other types of modulation. Based on our results we conclude that some promoter parameters are selected to make them blind to frequency modulation at the expense of not being optimal for amplitude codification.