Related Experiment Video
Updated: Jun 26, 2025
08:45
Determination of Mitochondrial Respiration and Glycolysis in Ex Vivo Retinal Tissue Samples
Published on: August 4, 2021
4.2K
Compartmental Differences in the Retinal Ganglion Cell Mitochondrial Proteome
Biorxiv : the Preprint Server for Biology
|May 20, 2024
Summary
Retinal ganglion cells (RGCs) have distinct mitochondrial proteins in their somatodendritic and axonal compartments. This difference in mitochondrial composition may reveal new therapeutic targets for optic neuropathies.
Area of Science:
- Neuroscience
- Cell Biology
- Biochemistry
Background:
- Retinal ganglion cells (RGCs) are vulnerable to mitochondrial dysfunction due to their unique polarization.
- Distinct cellular compartments of RGCs (somatodendritic and axonal) have different bioenergetic demands.
Approach:
- Developed a protocol to isolate intact mitochondria from mouse RGC somatodendritic and axonal compartments using RGC MitoTag mice.
- Utilized mass spectrometry to identify and quantify mitochondrial proteins in each compartment.
Key Points:
- Identified 471 proteins in somatodendritic mitochondria and 357 in axonal mitochondria.
- Discovered compartment-specific mitochondrial proteins: 10 exclusive to somatodendritic, 3 to axonal.
- Found enrichment of 19 proteins in somatodendritic and 18 in axonal mitochondria.
Conclusions:
- Compartmental differences in RGC mitochondrial protein composition were confirmed via immunofluorescence for SOD2, SFXN3, and HADHA.
- These findings offer potential therapeutic targets for optic neuropathies by understanding RGC mitochondrial biology.
More Related Videos
Related Concept Videos
01:39Mitochondrial Protein Sorting
4.3K
Mitochondria are double-membrane organelles of the eukaryotes involved in cellular metabolism, signaling, ATP synthesis, and programmed cell death. Each of these processes requires specific proteins and enzymes that must be correctly sorted to the right mitochondrial subcompartment for the proper functioning of the organelle.
Most of these mitochondrial proteins are encoded by the nucleus and imported to the mitochondria as unfolded or loosely folded precursors. Mitochondrial precursors...
Most of these mitochondrial proteins are encoded by the nucleus and imported to the mitochondria as unfolded or loosely folded precursors. Mitochondrial precursors...
4.3K
01:45Mitochondrial Membranes
10.0K
A single mitochondrion is a bean-shaped organelle enclosed by a double-membrane system. The outer membrane of mitochondria is smooth and contains many porins - the integral membrane transporters. Porins enable free diffusion of ions and small uncharged molecules through the outer mitochondrial membrane but limit the transport of molecules larger than 5000 Daltons. Further, the outer mitochondrial membrane forms a unique structure called membrane contact sites with other subcellular organelles,...
10.0K
01:19Translocation of Proteins into the Mitochondria
3.1K
Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
3.1K
01:28The Inner Mitochondrial Membrane
3.3K
The inner mitochondrial membrane is the primary site of ATP synthesis. The inner membrane domain that forms a smooth layer adjacent to the outer membrane is called the inner boundary membrane. This domain contains membrane transporters that drive metabolites in and out of the mitochondria. In contrast, the inner membrane network that invaginates into the matrix space is called the cristae membrane. This domain accounts for principle mitochondrial function as it accommodates the protein...
3.3K
01:12Porin Insertion in the Outer Mitochondrial Membrane
3.0K
Porins are beta-barrel proteins translocated to the mitochondrial outer membrane through the TOM complex into the intermembrane space. Porin precursors bind TIM chaperones within the intermembrane space and are guided to the Sorting and Assembly Machinery complex or SAM complex on the outer mitochondrial membrane.
Three models describe the assembly of porins by the SAM complex and their insertion into the outer membrane. Model 1 suggests that porins are assembled outside the SAM channel as the...
Three models describe the assembly of porins by the SAM complex and their insertion into the outer membrane. Model 1 suggests that porins are assembled outside the SAM channel as the...
3.0K