The assignment progress was achieved by matching the measurements (the mitochondrial position and morphology in current frame) with their prediction made by the IMM filter.
In pollen tubes, the evidence largely comes from inhibitor studies in which the anti-actin reagents, latrunculin B and jasplakinolide, interfere with mitochondrial positioning (Lovy-Wheeler et al. 2007) and dynamics (Zheng et al. 2010).
Furthermore, simultaneous visualization of mitochondria and actin filaments suggested that mitochondrial positioning might involve depolymerization of actin filaments on the surface of mitochondria.
Neuron cells are highly polarized cells, and thus the importance of mitochondrial positioning looms much larger than conventional cells.
Due to the uniform, polarized arrangement of MTs in axons and the critical importance of mitochondrial positioning to neuronal function, neurons have proven to be an excellent model system to study regulated mitochondrial transport and tethering (for in depth review see [ 90, 91]).
For example, ANC-1 mediated actin-LINCs in C. elegans have been identified as mitochondrial scaffolds, where ANC-1 mutants display defective mitochondrial positioning (Ref. 53).
It also raises the question of cause and effect: does the immaturity of young cultures contribute to mitochondrial motility, or does mitochondrial positioning reciprocally affect the stability of synapses?
As shown in Figure S3D, mitochondrial positioning was still visibly perturbed regardless whether division succeeds (middle row shows a representative cell) or fails (bottom row).
Recent research suggests that mitochondrial positioning in neurons relies on Ca2+ concentration as well as the ratio of ADP to ATP.
It is also unclear whether mitochondria play a role in Ca2+ buffering in the pollen tube or whether Ca2+ itself regulates mitochondrial positioning.
