title: Memory improves precision of cell sensing in fluctuating environments.
abstract: Biological cells are often found to sense their chemical environment near the single-molecule detection limit. Surprisingly, this precision is higher than simple estimates of the fundamental physical limit, hinting towards active sensing strategies. In this work, we analyse the effect of cell memory, e.g. from slow biochemical processes, on the precision of sensing by cell-surface receptors. We derive analytical formulas, which show that memory significantly improves sensing in weakly fluctuating environments. However, surprisingly when memory is adjusted dynamically, the precision is always improved, even in strongly fluctuating environments. In support of this prediction we quantify the directional biases in chemotactic Dictyostelium discoideum cells in a flow chamber with alternating chemical gradients. The strong similarities between cell sensing and control engineering suggest universal problem-solving strategies of living matter.
authors.affiliation: Department of Life Sciences and Centre for Systems Biology and Bioinformatics, Imperial College, London, SW7 2AZ, United Kingdom.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Aquino
authors.affiliation: 1] Department of Life Sciences and Centre for Systems Biology and Bioinformatics, Imperial College, London, SW7 2AZ, United Kingdom [2] Beatson Institute for Cancer Research, Glasgow, G61 1BD, UK.
authors.forename: Luke
authors.initials: L
authors.lastname: Tweedy
authors.affiliation: 1] Leiden Institute of Physics, Leiden University, Leiden, The Netherlands and [2] Center for NanoScience (CeNS), Ludwig-Maximilians-University, Geschwister-Scholl-Platz 1, 80539 Munich, Germany.
authors.forename: Doris
authors.initials: D
authors.lastname: Heinrich
authors.affiliation: Department of Life Sciences and Centre for Systems Biology and Bioinformatics, Imperial College, London, SW7 2AZ, United Kingdom.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Endres
mesh_terms: D000465:Algorithms; D002630:Chemotactic Factors / Q000502:physiology; D002633:Chemotaxis; D003198:Computer Simulation; D004023:Dictyostelium / Q000166:cytology / Q000502:physiology*; D044085:Microfluidics; D011956:Receptors, Cell Surface / Q000502:physiology
chemical_list: D002630:Chemotactic Factors; D011956:Receptors, Cell Surface