8/18/2019 Miro1 Regulates Mt Trafficking

1/14

Miro1 Regulates Activity Driven Positioning

Mitochondria within Astrocytic Processes Appose

Synapses to Regulate Intracellular Calcium Signaling

Terri-Leigh Stephen et al.

8/18/2019 Miro1 Regulates Mt Trafficking

2/14

Interaction between Presynaptic neuron and Ast

8/18/2019 Miro1 Regulates Mt Trafficking

3/14

Role of Miro1 in mitochondria mobilty

8/18/2019 Miro1 Regulates Mt Trafficking

4/14

Hypothesis

•

Miro1 regulates trafficking and retention of mitochondria inprocesses of astrocytes and synapse.

• This Miro1 regulated mitochondrial trafficking play a key rolintracellular calcium signaling.

8/18/2019 Miro1 Regulates Mt Trafficking

5/14

Results

8/18/2019 Miro1 Regulates Mt Trafficking

6/14

Fig 1: Basal

mitochondrial

traffickingdynamics

differ inAstrocytic

and Neuronal

processes

8/18/2019 Miro1 Regulates Mt Trafficking

7/14

Fig 2: Enhancingneuronal activity

alters mitochondrialtrafficking dynamics

and morphology inastrocyte processes.

8/18/2019 Miro1 Regulates Mt Trafficking

8/14

Fig 3: Neuronal activity induces astrocyte mitochondrial posnear synapses.

8/18/2019 Miro1 Regulates Mt Trafficking

9/14

Fig 4: Glutamatedecreases thefusion rate of

mitochondria inastrocytic processes

in situ.

8/18/2019 Miro1 Regulates Mt Trafficking

10/14

Fig 5: The Calcium

sensing EF hands

of Miro1 areessential for

regulatingmitochondrial

trafficking and

morphology inastrocytes in

primary cultures

8/18/2019 Miro1 Regulates Mt Trafficking

11/14

Fig 6: Mutant Miro1 expression in situ dirups the abilitmitochondria to response to neuronal activity and alte

trafficking

8/18/2019 Miro1 Regulates Mt Trafficking

12/14

Fig 7: Mutant Miro1 expression in slices disrupts

intracellularastrocytes Calcium signalling

8/18/2019 Miro1 Regulates Mt Trafficking

13/14

Pros

• The experiments are well organized and ordered.

•Establishes their hypothesis very well.

• Give rise to some important questions that can lead to potefuture researches.

8/18/2019 Miro1 Regulates Mt Trafficking

14/14

Cons

• The mechanism by which Calcium get entry into astrocyte is not they block NMDAR mitochondrial mobility get normal, it indicateget entry through NMDA channel is responsible, but astrocytes centry involve other Glutamate dependent channels and ion exchwhy blocking them wont affect mobility.

• They provide little emphasizes on mitochondrial fission and fusiospecially fission. It may be the proper way to answer why the

mitochondrial length decreased.• The authors just give a reference of Miro1 dependent Mitochond

trafficking in Neurons, but they don’t light up the mechanisms obe they can compare Neuronal and astrocytes Miro1 dependentMitochondrial trafficking in the discussion to clarify.