Messages diffuse faster than messengers
In many cell-signaling pathways, information is transmitted by the diffusion of messenger molecules. Diffusion coefficients characterize the messenger's spatial range and the characteristic times of signal propagation. Inside cells, particles usually diffuse in the presence of immobile binding...
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2006
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Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00278424_v103_n14_p5338_Pando http://hdl.handle.net/20.500.12110/paper_00278424_v103_n14_p5338_Pando |
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paper:paper_00278424_v103_n14_p5338_Pando2023-06-08T14:54:21Z Messages diffuse faster than messengers Binding Effective diffusion Fluorescence recovery after photobleaching Tagged particles Traps calcium carrier protein fluorescent dye article binding site calculation diffusion coefficient fluorescence recovery after photobleaching mathematical analysis nonhuman oocyte priority journal signal transduction time Xenopus laevis Animals Fluorescence Signal Transduction Xenopus laevis Cephalopoda Xenopus laevis In many cell-signaling pathways, information is transmitted by the diffusion of messenger molecules. Diffusion coefficients characterize the messenger's spatial range and the characteristic times of signal propagation. Inside cells, particles usually diffuse in the presence of immobile binding sites (or traps). It is well known that binding to traps results in an effective diffusion coefficient that is smaller than the free coefficient in media free of traps. To measure effective diffusion coefficients in cells, "tagged" particles are often used. Radioactive calcium was used in a giant squid axon and in cytosolic extracts of Xenopus laevis oocytes. Fluorescence recovery after photobleaching yields diffusion coefficients from observations of the distribution of fluorescently labeled proteins. In the absence of traps, free diffusion coefficients give both the rate at which single-particle mean square displacements increase and the rate at which information in the form of inhomogeneities in particle concentration spread out with time. We show here that, in the presence of traps, information diffuses faster than single particles. Thus, messages diffuse faster than messengers. Tagged-particle experiments give the single-particle diffusion coefficients and, thus, can underestimate the rate of diffusive signal propagation. © 2006 by The National Academy of Sciences of the USA. 2006 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00278424_v103_n14_p5338_Pando http://hdl.handle.net/20.500.12110/paper_00278424_v103_n14_p5338_Pando |
institution |
Universidad de Buenos Aires |
institution_str |
I-28 |
repository_str |
R-134 |
collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
topic |
Binding Effective diffusion Fluorescence recovery after photobleaching Tagged particles Traps calcium carrier protein fluorescent dye article binding site calculation diffusion coefficient fluorescence recovery after photobleaching mathematical analysis nonhuman oocyte priority journal signal transduction time Xenopus laevis Animals Fluorescence Signal Transduction Xenopus laevis Cephalopoda Xenopus laevis |
spellingShingle |
Binding Effective diffusion Fluorescence recovery after photobleaching Tagged particles Traps calcium carrier protein fluorescent dye article binding site calculation diffusion coefficient fluorescence recovery after photobleaching mathematical analysis nonhuman oocyte priority journal signal transduction time Xenopus laevis Animals Fluorescence Signal Transduction Xenopus laevis Cephalopoda Xenopus laevis Messages diffuse faster than messengers |
topic_facet |
Binding Effective diffusion Fluorescence recovery after photobleaching Tagged particles Traps calcium carrier protein fluorescent dye article binding site calculation diffusion coefficient fluorescence recovery after photobleaching mathematical analysis nonhuman oocyte priority journal signal transduction time Xenopus laevis Animals Fluorescence Signal Transduction Xenopus laevis Cephalopoda Xenopus laevis |
description |
In many cell-signaling pathways, information is transmitted by the diffusion of messenger molecules. Diffusion coefficients characterize the messenger's spatial range and the characteristic times of signal propagation. Inside cells, particles usually diffuse in the presence of immobile binding sites (or traps). It is well known that binding to traps results in an effective diffusion coefficient that is smaller than the free coefficient in media free of traps. To measure effective diffusion coefficients in cells, "tagged" particles are often used. Radioactive calcium was used in a giant squid axon and in cytosolic extracts of Xenopus laevis oocytes. Fluorescence recovery after photobleaching yields diffusion coefficients from observations of the distribution of fluorescently labeled proteins. In the absence of traps, free diffusion coefficients give both the rate at which single-particle mean square displacements increase and the rate at which information in the form of inhomogeneities in particle concentration spread out with time. We show here that, in the presence of traps, information diffuses faster than single particles. Thus, messages diffuse faster than messengers. Tagged-particle experiments give the single-particle diffusion coefficients and, thus, can underestimate the rate of diffusive signal propagation. © 2006 by The National Academy of Sciences of the USA. |
title |
Messages diffuse faster than messengers |
title_short |
Messages diffuse faster than messengers |
title_full |
Messages diffuse faster than messengers |
title_fullStr |
Messages diffuse faster than messengers |
title_full_unstemmed |
Messages diffuse faster than messengers |
title_sort |
messages diffuse faster than messengers |
publishDate |
2006 |
url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00278424_v103_n14_p5338_Pando http://hdl.handle.net/20.500.12110/paper_00278424_v103_n14_p5338_Pando |
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1768542305075068928 |