Saturday, July 17, 2021

Creation Moment 7/18/2021 - TRP, the built-in Navigation Tool of the Creator?

They were amazed,... Job 32:15

"Studies in brainless slime molds reveal that they use physical cues to decide where to grow. 
If you didn’t have a brain, could you still figure out where you were and navigate your surroundings
 
Thanks to new research on slime molds, the answer may be “yes.”

Scientists from the Wyss Institute and the Allen Discovery Center have discovered that a brainless slime mold called Physarum polycephalum uses its body to sense mechanical cues in its surrounding environment, and performs computations similar to what we call “thinking” to decide in which direction to grow based on that information.
 “People are becoming more interested in Physarum because it doesn’t have a brain but it can still perform a lot of the behaviors that we associate with thinking, like solving mazes, learning new things, and predicting events,” said first author Nirosha Murugan.
 
Slime molds are amoeba-like organisms that can grow to be up to several feet long, and help break down decomposing matter in the environment like rotting logs, mulch, and dead leaves. A single Physarum creature consists of a membrane containing many cellular nuclei floating within a shared cytoplasm, creating a structure called a syncytium. Physarum moves by shuttling its watery cytoplasm back and forth throughout the entire length of its body in regular waves, a unique process known as shuttle streaming.
 
The researchers placed Physarum specimens in the center of petri
dishes coated with a semi-flexible agar gel and placed either one or three small glass discs next to each other atop the gel on opposite sides of each dish. 
They then allowed the organisms to grow freely in the dark over the course of 24 hours, and tracked their growth patterns. For the first 12 to 14 hours, the Physarum grew outwards evenly in all directions; after that, however, the specimens extended a long branch that grew directly over the surface of the gel toward the three-disc region 70% of the time. Remarkably, the Physarum chose to grow toward the greater mass without first physically exploring the area to confirm that it did indeed contain the larger object.
 
To figure out the missing piece of the puzzle, the scientists used computer modeling to create a simulation of their experiment to explore how changing the mass of the discs would impact the amount of stress (force) and strain (deformation) applied to the semi-flexible gel and the attached growing Physarum. As they expected, larger masses increased the amount of strain, but the simulation revealed that the strain patterns the masses produced changed, depending on the arrangement of the discs.
Imagine that you are driving on the highway at night and looking for a town to stop at. You see two different arrangements of light on the horizon: a single bright point, and a cluster of less-bright points. While the single point is brighter, the cluster of points lights up a wider area that is more likely to indicate a town, and so you head there,” said co-author Richard Novak, Ph.D., a Lead Staff Engineer at the Wyss Institute. “The patterns of light in this example are analogous to the patterns of mechanical strain produced by different arrangements of mass in our model. Our experiments confirmed that Physarum can physically sense them and make decisions based on patterns rather than simply on signal intensity.
 
Q: But how was it detecting these strain patterns? 
A: The scientists suspected it had to do with Physarum’s ability to rhythmically contract and tug on its substrate, because the pulsing
and sensing of the resultant changes in substrate deformation allows the organism to gain information about its surroundings. Other animals have special channel proteins in their cell membranes called TRP-like proteins that detect stretching, and co-author and Wyss Institute Founding Director Donald Ingber, M.D., Ph.D had previously shown that one of these TRP proteins mediates mechanosensing in human cells. 
When the team created a potent TRP channel-blocking drug and applied it to Physarum, the organism lost its ability to distinguish between high and low masses, only selecting the high-mass region in 11% of the trials and selecting both high- and low-mass regions in 71% of trials."
SciTechDaily