Ramanujan Auditorium

Location & function of mitochondria in a neuronal process

Sandhya Koushika

Tata Institute of Fundamental Research Mumbai

Mitochondria are important cellular organelles used for ATP production and buffering cytosolic calcium. In neurons,
mitochondria are present in the cell body, along neuronal processes and are often enriched at regions of high energy demand.
The density of mitochondria remains unchanged through axon growth. Addition of a mitochondrion during neuron growth
can occur at any location along the neuronal process where two adjacent inter-mitochondrial intervals cross a threshold
in inter-mitochondrial distance suggesting signaling between adjacent mitochondria. Additionally we find that adjacent
inter-mitochondrial intervals are regulated through development occurring simultaneously with change in actin distribution.
Actin appears to play a role in distribution of axonal mitochondria and actin dynamics are also dependent on the presence of
mitochondria along axons. Such actin-dynamics appear essential for behaviour. Our data suggest a complex regulatory network
that maintains inter-mitochondrial intervals where the actin cytoskeleton may play a key role.