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Three-dimensional Imaging and Analysis of Mitochondria within Human Intraepidermal Nerve Fibers
Published on: September 29, 2017
Endoplasmic reticulum mediates mitochondrial transfer within the osteocyte dendritic network
Junjie Gao1,2,3, An Qin4, Delin Liu1,2
1Perron Institute for Neurological and Translational Science, Nedlands, Western Australia 6009, Australia.
Science Advances
|December 5, 2019
Summary
Osteocytes transfer mitochondria through dendritic networks to restore metabolic function in stressed cells. This process, crucial for tissue homeostasis, is mediated by endoplasmic reticulum-mitochondria contact involving Mitofusin 2.
Area of Science:
- Cell Biology
- Mitochondrial Biology
- Bone Biology
Background:
- Mitochondrial transfer is vital for tissue homeostasis and chemotherapy resistance.
- Osteocytes, with their interconnected dendritic networks, serve as a model for studying mitochondrial dynamics.
- Understanding mitochondrial transfer mechanisms is key to addressing age-related cellular dysfunction.
Purpose of the Study:
- To investigate the mechanism of mitochondrial transfer within osteocyte dendritic networks.
- To elucidate the role of endoplasmic reticulum (ER)-mitochondria contact in this process.
- To explore the impact of aging on mitochondrial transfer in osteocytes.
Main Methods:
- Utilized primary murine osteocytes with photoactivatable mitochondria (PhAM)floxed and MLO-Y4 cells.
- Employed high-resolution confocal imaging to visualize mitochondrial transfer.
- Assessed the role of Mitofusin 2 (Mfn2) and ER-mitochondria contact.
Main Results:
- Demonstrated mitochondrial transfer between osteocytes within dendritic networks.
- Showed that stressed osteocytes receiving mitochondria had restored metabolic function.
- Identified ER-mitochondria contact, mediated by Mfn2, as essential for mitochondrial transfer.
- Observed a decline in Mfn2 expression with age, correlating with impaired mitochondrial transfer.
Conclusions:
- ER-mitochondria contact is a previously unrecognized mechanism for mediating mitochondrial transfer.
- Mfn2 plays a predominant role in facilitating mitochondrial transfer within osteocyte networks.
- Age-related decline in Mfn2 impairs mitochondrial distribution and transfer, impacting osteocyte homeostasis.
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