Dendritic spine morphology regulates calcium-dependent synaptic weight change

Abstract

Dendritic spines act as biochemical computational units and must adapt their responses according to their activation history. Calcium influx acts as the first signaling step during postsynaptic activation and is a determinant of synaptic weight change. Dendritic spines also come in a variety of sizes and shapes. To probe the relationship between calcium dynamics and spine morphology, we used a stochastic reaction-diffusion model of calcium dynamics in idealized and realistic geometries. We show that despite the stochastic nature of the various calcium channels, receptors, and pumps, spine size and shape can modulate calcium dynamics and subsequently synaptic weight updates in a deterministic manner. Through a series of exhaustive simulations and analyses, we found that the calcium dynamics and synaptic weight change depend on the volume-to-surface area of the spine. The relationships between calcium dynamics and spine morphology identified in idealized geometries also hold in realistic geometries, suggesting that there are geometrically determined deterministic relationships that may modulate synaptic weight change.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jul 12, 2022
Source ID
10.1085/jgp.202112980

Entities

People

  • Christopher T Lee
  • Maven V. Holst
  • Miriam Bell
  • Padmini Rangamani

Organizations

  • Air Force Office of Scientific Research
  • Hartwell Foundation
  • National Institute of General Medical Sciences
  • University of California, San Diego

Tags

Fields of Study

  • Biology

Readers

  • Cellular and Molecular Pathways of Apoptosis.
  • Computational Fluid Dynamics (CFD)
  • Molecular and Cellular Biochemistry