As a carnivorous plant, Venus flytraps have always been a fascinating subject of study. One of their many mysteries is how they differentiate an insect visit from less nutritious stimulants such as a windblown pebble. Now scientists are one step closer to deciphering the underlying mechanism, assisted by a new ability to visualize calcium changes in real time.
Calcium has long been suspected to play an important part in a Venus flytrap’s close/no-close decision process, but scientists couldn’t verify their hypothesis before. Standard chemical tests for calcium would require cutting the plant apart, which would only result in a static snapshot. The software analogy would be killing the process for a memory dump but unable to debug the process at runtime. There were tantalizing hints of a biological calcium-based analog computer at work, but mother nature had no reason to evolve JTAG test points on it.
Lacking in-circuit debug headers, scientists turned to the next best thing: add diagnostic indicator lights. But instead of blinking LEDs, genes were added to produce a protein that glows in the presence of calcium. Once successful, they could work with the engineered plants and get visual feedback. Immediately see calcium levels change and propagate in response to various stimuli over different time periods. Confirming that the trap snaps shut only in response to patterns of stimuli that push calcium levels beyond a threshold.
With these glowing proteins in place, researchers found that calcium explained some of the behavior but was not the whole picture. There’s something else, suspected to be a fast electrical network, that senses prey movement and trigger calcium release. That’ll be something to dig into, but at least we have more experience working with electrical impulses and not just for plants, either.
Continue reading “Illuminating The Inner Workings Of A Venus Flytrap”
Join us on Wednesday at noon Pacific time for the open-source biology and biohacking Hack Chat!
Justin Atkin‘s name might not ring a bell, but you’ve probably seen his popular YouTube channel The Thought Emporium, devoted to regular doses of open source science. Justin’s interests span a wide range, literally from the heavens above to the microscopic world.
His current interest is to genetically modify yeast to produce spider silk, and to perhaps even use the yeast for brewing beer. He and the Thought Emporium team have been busy building out a complete DIY biology lab to support the effort, and have been conducting a variety of test experiments along the way.
Please join us for this Hack Chat, in which we’ll cover:
- The how’s and why’s of yeast genetic engineering;
- What it takes to set up an effective biology lab from scratch;
- An update on the current status of the spider-silk yeast project; and
- Where the open-source biology field is, and where it’s going.
You are, of course, encouraged to add your own questions to the discussion. You can do that by leaving a comment on the Open-Source Biology and Biohacking Hack Chat event page and we’ll put that in the queue for the Hack Chat discussion.
Our Hack Chats are live community events on the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, February 13, at noon, Pacific time. If time zones have got you down, we have a handy time zone converter.
Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.
Would you pop a homemade pill containing genetically engineered virus particles just so that you can enjoy a pizza? Not many people would, but then again, if you’ve experienced the violent reaction to lactose that some people have, you just might consider it.
Such was the position that [The Thought Emporium] found himself in at age 16, suddenly violently lactose intolerant and in need of a complete diet overhaul. Tired of scanning food labels for telltale signs of milk products and paying the price for the inevitable mistakes, he embarked on a journey of DIY gene therapy to restore his ability to indulge in comfort foods. The longish video below details a lot of that journey; skip to 15:40 if you want to cut to the chase. But if you’re at all interested in the processes of modern molecular biology, make sure you watch the whole thing. The basic idea here is to create an innocuous virus that carries the lac gene, which encodes the enzyme β-galactosidase, or lactase, and use it to infect the cells of his small intestine. There the gene will hopefully be expressed, supplementing the supply of native enzyme, which in most adult humans is no longer expressed at the levels it was when breast milk was our primary food.
Did it work? We won’t ruin the surprise, but in any case, the video is a fascinating look at mammalian cell transfection and other techniques of genetic engineering that are accessible to the biohacker. Still, it takes some guts to modify your own guts, but bear in mind that this is someone who doesn’t mind inserting magnetic implants in his fingers.
Continue reading “Biohacking Lactose Intolerance”
One of the essential problems of bio-robotics is actuators. The rotors, bearings, and electrical elements of the stepper motors and other electromechanical drives we generally turn to for robotics projects are not really happy in living systems. But building actuators the way nature does it — from muscle tissue — opens up a host of applications. That’s where this complete how-to guide on building and controlling muscle-powered machines comes in.
Coming out of the [Rashid Bashir] lab at the University of Illinois at Urbana-Campaign, the underlying principles are simple, which of course is the key to their power. The technique involves growing rings of muscle tissue in culture using 3D-printed hydrogel as forms. The grown muscle rings are fitted on another 3D-printed structure, this one a skeleton with stiff legs on a flexible backbone. Stretched over the legs like rubber bands, the muscle rings can be made to contract and move the little bots around.
Previous incarnations of this technique relied on cultured rat heart muscle cells, which contract rhythmically of their own accord. That yielded motion but lacked control, so for this go-around, [Bashir] et al used skeletal muscle cells genetically engineered to contract when exposed to light. Illuminating different parts of the muscle ring lets the researchers move the bio-bots anywhere they want. They can also use electric stimulation to control the bio-bots.
The method isn’t quite at the point where home lab biohackers will start churning out armies of bio-bots. But the paper is remarkably detailed in methods and materials, from the CAD files for 3D-printing the forms and bio-bot skeletons to a complete troubleshooting guide. It’s all there, and it could be a game changer for developing the robotic surgeons of the future.
Continue reading “Genetically Engineered Muscle Cells Power Tiny Bio-Robots”
Once upon a time, the aspiring nerdling’s gift of choice was the Gilbert chemistry set. Its tiny vials of reagents, rack of test tubes, and instruction book promised endless intellectual stimulation and the possibility of stink bombs on demand. Now a new genetic engineering lab-in-a-box Kickstarter, with all the tools and materials needed to create your own transgenic organisms, may help the young biohacker’s dreams come true.
The Kickstarter has been wildly successful. The initial goal was $1200AUD was met in a day, and currently stands at almost $6200AUD. Despite that success, color me skeptical on this one. Having done way more than my fair share of gene splicing, there seem to be a few critical gaps in this kit. For example, the list of materials for the full kit includes BL21 competent E. coli as the host strain. Those cells are designed to become porous to extracellular DNA when treated with calcium chloride and provided with a heat shock of 42°C. At a minimum I’d think they’d include a thermometer so you can control the heat shock process. Plenty of other steps also need fairly precise incubations, like the digestion and ligation steps needed to get your gene into the host. And exactly what technique you’d be using to harvest DNA from the animal, plant or fungal cells is unclear; the fact that most of the techniques for doing so require special techniques leads me to believe there’s a lot less here than meets the eye.
To be fair, I’ve been off the lab bench for the better part of two decades, and the state of the art has no doubt advanced in that time. There could very well be techniques I’m not familiar with that make the various steps needed to transform a bacterial culture with foreign DNA trivial. It could also be the case that the techniques I used in the lab were optimized for yield and for precise data, while the GlowGene kit provides the materials to get a “good enough” result. I hope so, because a kit like this could really expand the horizons of hackerdom and start getting the biohacking movement going.