Spatial and temporal aspects of cellular calcium signals : 'elementary' signals and waves / by Prof. Ian Parker.

Format:

Video

Author/Creator:

Parker, Ian, author.

Language:

English

Subjects (All):

Cellular signal transduction.

Calcium--Physiological effect.

Calcium.

Physical Description:

1 videorecording (57 min., 34 sec.) : sound, color

Other Title:

Spatial and temporal aspects of cellular calcium signals

Place of Publication:

London : Henry Stewart Talks Ltd, 2007.

System Details:

video file

Summary:

Audio-visual presentation : Calcium as a life and death cellular messenger ; Sequestration and liberation of calcium from the endoplasmic reticulum ; Calcium release through inositol trisphosphate receptors and modulation by calcium ; Optical techniques to visualize and stimulate intracellular calcium signals ; 'Elementary' calcium signals through single channels and clusters of channels ; Generation of periodic calcium waves by stochastic elementary events ; Modulation of calcium signals by calcium binding proteins ; The hierarchical organization of cellular calcium signals.

Contents:

Introduction

Biophysics of Ca signaling

Extracellular and intracellular calcium sources

Diffusion limits the spread of Ca ions in a cell

Ca diffusion in the cytosol is slowed by Ca buffers

Spatial aspects of Ca signaling

Ca feedback on the IP3 receptor

Ca induced Ca release propagates Ca waves

Experimental methods

Fluorescence microscopy

Conventional fluorescence image of pollen grain

Confocal sections through pollen grain

Caged IP4

Line-scanning confocal microscope - the system

Line-scanning confocal microscope - results

The experimental system: oocyte of X. laevis

'Elementary' calcium release events

'Local' Ca "puffs" in the Xenopus oocyte

Linescan imaging of puffs

Triggering of Ca waves by puffs

Model of local and global IP3-evoked Ca signals

The spread of Ca during elementary events

Ca signals show a continuum of sizes

Kinetics of puffs

Puff occurrence is stochastic

Saltatory propagation of Ca waves between puffs

Triggering of calcium waves by puffs

Method for rapidly changing [IP3] and [Ca] (1)

Both photolysis and UV zap simultaneously

Ca amount in a puff is too small to trigger a wave

Role of puffs in setting frequency of Ca waves

Puffs occur between, and trigger, Ca waves

The regular periodicity of Ca waves

Failure of puffs to trigger a wave

Wave triggering depends on Ca accumulation

Focal wave initiation sites are more IP3-sensitive

Ca buffers affect coupling between puff sites

Ca buffering proteins

'Slow' vs. 'fast' Ca buffers

Conclusions

Why are Ca channels organized in clusters?

Acknowledgements.

Notes:

Description based on publisher supplied metadata and other sources.

Retrieved April 7, 2024, from https://hstalks.com/bs/416/.