Hunting secrets of the Venus flytrap (hint: they can count)

January 21, 2016
The red dots are glands. When the trap closes, forming a green stomach, these glands release a lytic enzyme cocktail, digest the victim, and incorporate the nutrients release from the building blocks of the meat. Credit: Sönke Scherzer

Carnivorous plants such as the Venus flytrap depend on meals of insects to survive in nutrient-poor soil. They sense the arrival of juicy insects, lured by the plants' fruity scent, with the aid of sensitive trigger hairs on the inner surfaces of their traps. Now, researchers reporting in the Cell Press journal Current Biology on January 21 have looked more closely at exactly how the plants decide when to keep their traps shut and begin producing their acidic, prey-decomposing cocktail of enzymes. The short answer is: they count.

"The carnivorous plant Dionaea muscipula, also known as Venus flytrap, can count how often it has been touched by an insect visiting its capture organ in order to trap and consume the animal prey," says Rainer Hedrich of Universität Würzburg in Germany.

To find out whether Venus flytraps record touches, in the new study Hedrich and his colleagues fooled the into thinking they'd landed an insect by applying increasing numbers of mechano-electric stimuli to their trap and monitoring their responses. The studies show that a single touch to the trigger hair is enough to generate a response, setting the trap into a "ready-to-go" mode. In other words, the plants make note but don't snap just yet. It might be a false alarm, after all.

With the second stroke, the trap closes around the prey to form what Hedrich and his colleagues liken to a green stomach. As the prey attempt to escape, they wind up touching the mechano-sensitive trigger hairs again and again, which serves only to excite the plant further.

At this stage, the plant begins to produce a special touch hormone. After five triggers, glands on the inner surface of the trap also produce digestive enzymes and transporters to take up nutrients. Hedrich calls it a "deadly spiral of capture and disintegration." This input also allows the plant to scale its production of costly ingredients to the size of the meal.

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This is the video abstract for "The Venus Flytrap Dionaea muscipula CountsPrey-Induced Action Potentialsto Induce Sodium Uptake," published in Current Biology. Credit: Böhm and Scherzer et al./Current Biology 2016

"The number of action potentials informs [the plant] about the size and nutrient content of the struggling prey," Hedrich said. "This allows the Venus flytrap to balance the cost and benefit of hunting."

Interestingly, the plants show a particularly marked increase in production of a transporter that allows them to take up sodium. It's not clear exactly what the salt does for the plant, but the researchers suggest that it may have something to do with how Venus flytraps maintain the right balance of water inside their cell walls.

The video will load shortly
A fly touching (stepping on) a flytrap's sensory hair evokes signals also known as action potentials at is memorized as "there might be a potential prey" visiting. Upon the second insect-hair contact (with head), the trap closes within the blink of an eye. Credit: Böhm and Scherzer et al.

Hedrich and his colleagues are now sequencing the Venus flytrap genome. In those sequences, they expect to find additional clues about the plants' sensory systems and chemistry needed to support a carnivorous lifestyle and how those traits have evolved over time.

Explore further: Snaring bigger bugs gave flytraps evolutionary edge

More information: Current Biology, Böhm and Scherzer et al.: "The Venus Flytrap Dionaea muscipula Counts Prey-Induced Action Potentials to Induce Sodium Uptake" dx.doi.org/10.1016/j.cub.2015.11.057

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8 comments

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betterexists
1 / 5 (2) Jan 21, 2016
Why NOT Create Venus flytrap withOUT Insect Trapping Skill?
What for is CRISPR? Just to Show Nobel Medal?
Once it is done, that same ability may be SLOWLY transferred to several other close species!
If not, What for is Science?
IT IS REALLY VERY AMUSING TO READ about Types of Research saying that Dogs Do Feel Guilt like humans...or something like that.
betterexists
1 / 5 (1) Jan 21, 2016
If only Cactus can be made to trap Rats & Mice!
betterexists
1 / 5 (1) Jan 21, 2016
If only Cactus can be made to trap Rats & Mice!

Gotcha!
betterexists
1 / 5 (1) Jan 21, 2016
If we don't let it to Photosynthesize (by subjecting to total darkness forever...no light for even a second), but feed it an abundant supply of insects that cannot escape...WHAT HAPPENS?
Can it be 100% Carnivorous, I mean!
I saw dog eating grass video on youtube recently. If only they can survive on Termites, WoW!
betterexists
1 / 5 (1) Jan 21, 2016
Plants behaving like Animals, Very Fuuny...particularly after learning about it long time back.
Robots need Batteries or Power through Power Cord...If only they can CHEW on Mice & Function, WoW!
24volts
5 / 5 (4) Jan 21, 2016
If we don't let it to Photosynthesize (by subjecting to total darkness forever...no light for even a second), but feed it an abundant supply of insects that cannot escape...WHAT HAPPENS?
Can it be 100% Carnivorous, I mean!
I saw dog eating grass video on youtube recently. If only they can survive on Termites, WoW!


The plant will die without sunlight. It lives in very poor soil and needs the insects for the various vitamins, minerals, etc.... it gets from them. I live in Wilmington NC, the only area where they grow naturally. They normally live in marshy sandy soil.
betterexists
1 / 5 (2) Jan 21, 2016
And This week U.S. Dept of Defense announces plans to connect Human Brain to Supercomputer. The NESD program is part of the BRAIN (Brain Research through Advancing Innovative Neurotechnologies) Initiative launched in 2013. You can read more about that at the DARPA web site.
betterexists
not rated yet Feb 01, 2016
Why NOT remove that Animal-like feature from that plant by stripping away its genes one by one.
Later on, ATTEMPT to add those genes 1 by 1 to several plants until they will attempt SOMETHING in that fashion!

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