Diffusion-trapping model of receptor trafficking in dendrites.
We present a model for the diffusive trafficking of protein receptors along the surface of a neuron's dendrite. Distributed along the dendrite are spatially localized trapping regions that represent submicrometer mushroom-like protrusions known as dendritic spines. Within these trapping regions receptors can be internalized via endocytosis and either reinserted into the surface via exocytosis or degraded. We calculate the steady-state distribution of receptors along the dendrite assuming a constant flux of receptors inserted at one end, adjacent to the soma where receptors are synthesized, and use this to investigate the effectiveness of membrane diffusion as a transport mechanism. We also calculate the mean first passage time of a receptor to travel a certain distance along the cable and use this to derive an effective surface diffusivity.
Bressloff
P C
PC
Department of Mathematics, University of Utah, Salt Lake City, UT 84112, USA.
Earnshaw
B A
BA
D000818:Animals; D001703:Biophysics / Q000379:methods*; D002465:Cell Movement; D003712:Dendrites / Q000378:metabolism / Q000502:physiology*; D049229:Dendritic Spines / Q000378:metabolism; D004058:Diffusion; D004705:Endocytosis; D005089:Exocytosis; D006801:Humans; D008954:Models, Biological; D015233:Models, Statistical; D009474:Neurons / Q000378:metabolism; D011506:Proteins / Q000737:chemistry
D011506:Proteins