Re:Lasers activate killer instinct in mice
by Balgair on Friday January 13, 2017 @07:31PM
(#13396024)
Thats pretty much right, but it's not the viruses that are interacting with the light.
The virus is injected, and then infects cells. It re-writes their DNA, like a lot of viruses we are all made sick by, and inserts a DNA code into the cell. In wild viruses, that DNA code would make other viruses and start the process of infection all over again. Here, that DNA code is for a protein called an 'opsin'. Just like in your retina and eyes, this opsin protein is affect by light of certain colors. In the case of exciting the nerve cell to 'fire' (the other general case is inhibiting the cell from 'firing') the opsin protein is in the cell wall and opens up the cell to the extra-cellular environment. Similar to osmosis, this causes some of the ions in the fluids (Sodium, Potassium, Calcium, etc) to rush in or out of the cell. The specifics depend a lot on the particular cell, but mostly on the relative concentration of the ions in the cell and in the extracellular fluids.
Shine light, the protein (delivered via viral infection) opens, ions rush in/out, the cell 'fires'.
Also, in longer axons like in the eye or the spine, you do have cross talk like with copper wires. BUT only if those axons are un-myelinated. That is bio-talk for cells that wrap around the axons of nerve cells that are very fatty in composition. Basically, myelin is like the plastic insulation you have on copper wire. They do a lot of other things too, but in the spine and eye, they act as isolators for the nerves that have to go a long distance. When that myelin 'goes wrong', you can get disorders like ALS and such.
Here are some sources to learn more about optogentics:
The virus is injected, and then infects cells. It re-writes their DNA, like a lot of viruses we are all made sick by, and inserts a DNA code into the cell. In wild viruses, that DNA code would make other viruses and start the process of infection all over again. Here, that DNA code is for a protein called an 'opsin'. Just like in your retina and eyes, this opsin protein is affect by light of certain colors. In the case of exciting the nerve cell to 'fire' (the other general case is inhibiting the cell from 'firing') the opsin protein is in the cell wall and opens up the cell to the extra-cellular environment. Similar to osmosis, this causes some of the ions in the fluids (Sodium, Potassium, Calcium, etc) to rush in or out of the cell. The specifics depend a lot on the particular cell, but mostly on the relative concentration of the ions in the cell and in the extracellular fluids.
Shine light, the protein (delivered via viral infection) opens, ions rush in/out, the cell 'fires'.
Also, in longer axons like in the eye or the spine, you do have cross talk like with copper wires. BUT only if those axons are un-myelinated. That is bio-talk for cells that wrap around the axons of nerve cells that are very fatty in composition. Basically, myelin is like the plastic insulation you have on copper wire. They do a lot of other things too, but in the spine and eye, they act as isolators for the nerves that have to go a long distance. When that myelin 'goes wrong', you can get disorders like ALS and such.
Here are some sources to learn more about optogentics:
https://en.wikipedia.org/wiki/Optogenetics
https://www.youtube.com/watch?v=Nb07TLkJ3Ww