Mitochondria-Dynamic Organelles

The axon is thinner in diameter than the varicosity and also significantly thinner than the diameter of the mitochondria. Mitochondria must undergo structural modifications to be transported up or down the axon. These spatial restrictions imply that mitochondria are undergoing major structural remodeling or, alternatively, that these physical restrictions are a barrier to transport and that mitochondria are largely immobile once established at their locations down the axon. See Fischer et al (2018) for more discussion. Our goals are to:

• Determine the mechanisms of mitochondrial transport and how the transport is impacted following Traumatic Brain Injury.
• Determine how mitochondrial structure adapts to the physical constraints and metabolic demand in different neuronal compartments

Mitochondria purified from the hippocampus were cryopreserved and imaged with cryo-electron tomography. One of the dominant morphologies (image at right) exhibits extensive and well-developed crista evident as the blue membranous structures inside the outer membrane (in green). Defining the mechanisms that control crista density and overall mitochondrial size are critical to understand how mitochondria modify their function and transport in the complicated neuronal architecture. Our goals are to:

• Determine how metabolic status affects the structure and function of mitochondria by employing cryo-EM and Seahorse respiration.
• Characterize the structure and function of mitochondria isolated from different neuronal compartments.