title: Cell development obeys maximum Fisher information.
abstract: Eukaryotic cell development has been optimized by natural selection to obey maximal intracellular flux of messenger proteins. This, in turn, implies maximum Fisher information on angular position about a target nuclear pore complex (NPR). The cell is simply modeled as spherical, with cell membrane (CM) diameter 10 micrometer and concentric nuclear membrane (NM) diameter 6 micrometer. The NM contains approximately 3000 nuclear pore complexes (NPCs). Development requires messenger ligands to travel from the CM-NPC-DNA target binding sites. Ligands acquire negative charge by phosphorylation, passing through the cytoplasm over Newtonian trajectories toward positively charged NPCs (utilizing positive nuclear localization sequences). The CM-NPC channel obeys maximized mean protein flux F and Fisher information I at the NPC. Therefore the first-order change in I = 0. But also, the 2nd-order change in I is likewise close to zero, indicating significant stability to environmental perturbations. Many predictions are confirmed, including the dominance of protein pathways of from 1-4 proteins, a 4 nm size for the EGFR protein and the flux value F approximately 10(16) proteins/m2-s. After entering the nucleus, each protein ultimately delivers its ligand information to a DNA target site with maximum probability, i.e. maximum Kullback-Liebler entropy H(KL). In a smoothness limit H(KL) --> I(DNA)/2, so that the total CM-NPC-DNA channel obeys maximum Fisher I. It is also shown that such maximum information --> a cell state far from thermodynamic equilibrium, one condition for life.
authors.affiliation: College of Optical Sciences, University of Arizona, Tucson, Arizona 85721, USA. roy.frieden@optics.arizona.edu
authors.forename: B Roy
authors.initials: BR
authors.lastname: Frieden
authors.forename: Robert A
authors.initials: RA
authors.lastname: Gatenby
mesh_terms: D003585:Cell Biology; D004247:DNA / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D013816:Thermodynamics
chemical_list: D008565:Membrane Proteins; D004247:DNA