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Analyses of Mitochondrial Calcium Influx in Isolated Mitochondria and Cultured Cells
Published on: April 27, 2018
Mitochondrial Ca(2+) mobilization is a key element in olfactory signaling
Daniela Fluegge1, Lisa M Moeller, Annika Cichy
1Department of Chemosensation, Institute for Biology II, Rheinisch-Westfälische Technische Hochschule Aachen University, Aachen, Germany.
Nature Neuroscience
|March 27, 2012
Summary
Mitochondria are crucial for olfactory sensory neuron (OSN) function, regulating calcium dynamics and maintaining signal sensitivity. Impaired mitochondrial function transforms these neurons into simple detectors, losing their intensity encoding ability.
Area of Science:
- Neuroscience
- Cell Biology
- Sensory Physiology
Background:
- Cytosolic calcium (Ca2+) is vital for regulating gain and sensitivity in olfactory sensory neurons (OSNs).
- While some molecular components of OSN Ca2+ dynamics are known, critical details remain elusive.
Purpose of the Study:
- To investigate the physiological role of mitochondrial Ca2+ mobilization in mouse OSNs.
- To elucidate how mitochondria impact olfactory signaling dynamics and neuronal function.
Main Methods:
- Utilized a novel mitochondrial Ca2+ imaging technique.
- Combined with patch-clamp recordings, organelle mobility assays, and ultrastructural analyses.
Main Results:
- Mitochondrial Ca2+ mobilization shapes cytosolic Ca2+ responses during olfactory stimulation.
- This process ensures a wide dynamic response range and maintains the sensitivity of spike generation.
- Impaired mitochondrial function compromises the intensity encoding capacity of OSNs.
- Mitochondria are recruited to olfactory knobs in an activity-dependent manner to preserve cellular homeostasis and signaling integrity.
Conclusions:
- Mitochondria play a critical role in olfactory signaling by modulating Ca2+ dynamics.
- Mitochondrial Ca2+ handling is essential for OSNs to function as intensity encoders.
- Activity-dependent mitochondrial recruitment is a key mechanism for maintaining olfactory neuron function.
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