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Cells solved Henry VIII's infamous hedge maze by 'seeing around corners,' video shows:

For a single cell, the human body is a gargantuan maze of tissues, chemicals and capillaries, crammed full with trillions of other cells all bustling about like commuters at the world's busiest train station. Somehow, amidst all this hubbub, most cells still manage to reach their destinations.

How do they do it? Many cells have a trick up their sleeves known as chemotaxis —essentially, the ability to navigate by sensing the presence or absence of chemical attractants in the environment. Sperm cells use chemotaxis to find eggs, white blood cells use it to rally around infection sites and cancer cells use it to metastasize through vulnerable tissues.

[...] In their new study, the researchers focused on a specific form of cell navigation called "self-generated" chemotaxis. It relies on a simple philosophy: cells want to move from areas of a lower concentration of attractant (in this case, an acidic solution called adenosine monophosphate) into areas with a higher concentration.

[...] But sometimes there are multiple "fields" to choose from, illustrated in this study by the multiple branching paths of a maze. To determine which branch holds the higher concentration of attractant, cells break down the molecules in front of them, causing attractant from the nearby areas to diffuse toward them. As the cells move forward, the attractant ahead of them depletes more and more; eventually, short, dead-end branches of the maze are totally depleted of attractant, even before the cells reach the exit to a dead end. When faced with a short, depleted branch and a long, attractant-filled branch, the cells will never take the dead-end route, Insall said.

[...] Mazes ranged from easy (just a few branching paths before the exit) to difficult (with long dead-end paths, like the Hampton Court hedge maze[*] replica) to impossible (according to Insall, a replica of Scotland's Traquair House maze had to be scrapped, because all the amoebas kept dying before they solved the puzzle).

[...] The longest mazes took about 2 hours for the savvy cells to solve, Insall said, while the shorter ones took just 30 minutes.

[*] Hampton Court Maze on Wikipedia.

Journal Reference:
Luke Tweedy, Peter A. Thomason, Peggy I. Paschke, et al. Seeing around corners: Cells solve mazes and respond at a distance using attractant breakdown [$], Science (DOI: 10.1126/science.aay9792) (Direct Link)

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