Learn about the RLR gene editing tool; Victorian-era emoji; and why “night shift” screen settings don’t help you sleep. RLR is a new gene editing tool that's safer and more useful than CRISPR by Cameron Duke Move over CRISPR, the retrons are coming. (2021). EurekAlert! https://www.eurekalert.org/pub_releases/2021-04/wifb-moc042921.php Schubert, M. G., Goodman, D. B., Wannier, T. M., Kaur, D., Farzadfard, F., Lu, T. K., Shipman, S. L., & Church, G. M. (2021). High-throughput functional variant screens via in vivo production of single-stranded DNA. Proceedings of the National Academy of Sciences, 118(18), e2018181118. https://doi.org/10.1073/pnas.2018181118 Swingle, B., Markel, E., & Cartinhour, S. (2010). Oligonucleotide recombination: A hidden treasure. Bioengineered Bugs, 1(4), 265–268. https://doi.org/10.4161/bbug.1.4.12098 Irving, M. (2021, May 4). Harvard gene-editing tool “sneaks” DNA into cells without making cuts. New Atlas. https://newatlas.com/biology/retron-library-recombineering-gene-editing-crispr/ Are Retrons the Next CRISPR? | Cell And Molecular Biology. (2021). Labroots. https://www.labroots.com/trending/cell-and-molecular-biology/20347/retrons-crispr Flowers Were Emoji For Victorians by Anna Todd Romie Stott. (2016, August 15). How Flower-Obsessed Victorians Encoded Messages in Bouquets. Atlas Obscura; Atlas Obscura. https://www.atlasobscura.com/articles/how-flowerobsessed-victorians-encoded-messages-in-bouquets The meaning of flowers, Floriography, language of flowers, advice hints and tips from All Florists.co.uk. Allflorists.co.uk. http://www.allflorists.co.uk/advice_flowerMeanings.asp "Night shift" screen settings don't really help you sleep by Kelsey Donk Is night shift really helping you sleep better? (2021). EurekAlert! https://www.eurekalert.org/pub_releases/2021-04/byu-ins042621.php Duraccio, K. M., Zaugg, K. K., Blackburn, R. C., & Jensen, C. D. (2021). Does iPhone night shift mitigate negative effects of smartphone use on sleep outcomes in emerging adults? Sleep Health. https://doi.org/10.1016/j.sleh.2021.03.005 Follow Curiosity Daily on your favorite podcast app to learn something new every day withCody Gough andAshley Hamer — for free!
Learn about the RLR gene editing tool; Victorian-era emoji; and why “night shift” screen settings don’t help you sleep.
RLR is a new gene editing tool that's safer and more useful than CRISPR by Cameron Duke
Flowers Were Emoji For Victorians by Anna Todd
"Night shift" screen settings don't really help you sleep by Kelsey Donk
Follow Curiosity Daily on your favorite podcast app to learn something new every day with Cody Gough and Ashley Hamer — for free!
Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/move-over-crispr-new-gene-editing-tech-is-here
CODY: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from curiosity-dot-com. I’m Cody Gough.
ASHLEY: And I’m Ashley Hamer. Today, you’ll learn about a new gene editing tool that’s safer and more useful than CRISPR; the Victorian-era equivalent of emoji; and why “night shift” screen settings don’t really help you sleep.
CODY: Let’s satisfy some curiosity.
[CODY: So Ashley, we’re starting the week pretty light this week. You’ve got a fluffy little story about, what was it again? Oh yeah — the future of the human race?] [ad lib]
ASHLEY: You’ve heard us talk about CRISPR-cas9; that’s a method of gene editing that revolutionized the concept of genetic engineering. It’s sometimes described as a genetic cut-and-paste tool that can cut out any gene you want, which enables scientists to create brand new genomes. As big of a deal as it is, though, it turns out that CRISPR has its problems. Luckily, new research suggests there might be a better way.
For a refresher, CRISPR-cas9 is a programmable protein. It’s like a dog that can be shown a series of letters that comprise a particular genetic sequence and then sniff that sequence out of an incredibly large genome. When it finds it, it bites, which breaks the DNA. That’s how scientists have been able to do everything from eliminating HIV from infected cells to creating new, non-GMO crops.
CRISPR is incredibly precise, but it has some weaknesses. When you edit a genome, your goal is often to insert new information. CRISPR is absolutely terrible at this. It’s great at cutting DNA, but the rest of the technique relies on the cell’s own DNA repair mechanisms to insert the genetic sequence you want it to. That’s not easy to do, and even when it’s successful, it takes a really long time to engineer a large number of cells.
But scientists have recently developed something that lets them edit genes with no cutting required. It involves using retrons, which are little sequences of bacterial DNA, not robots that wear bell bottoms.
But while most DNA sequences are translated into proteins, retrons are translated into free-floating single-stranded DNA segments.
As described in a recent paper, Harvard scientists found out that they could load bits of circular DNA, called plasmids, with retron sequences of their own design. They embedded a retron with a gene for antibiotic resistance, along with special proteins that glue DNA strands together. Then, they injected the whole thing into E. coli bacteria. Soon, the dividing bacterial cell made copies of the new gene from the retron while the gluing protein tucked those free floating strands into the daughter cell’s genome — all without ever making a cut.
Because there are no cuts, this technique is thought to be safer than CRISPR. And because it can be used in many cells at once, experiments using the technique are faster and easier. Not only that, but these researchers also figured out how to barcode these mutations in a technique called retron library recombineering, or RLR. That lets them screen the entire pool of cells at once to figure out which ones have the mutations, which makes experiments even faster.
CRISPR was definitely a game changer for genetic engineering. But with retrons at our disposal, it may have just been the beginning.
Emoji are supposed to add meaning to a message, but sometimes they just cause confusion. Does that winky face mean they’re joking? Or are they flirting? It’s hard to know! Believe it or not, lovers from the Victorian era faced the same issue. Only instead of emoji, they filled bouquets with specific flowers that had hidden meanings..
If you lived in the Victorian era when floriography was in vogue, it would be crucial to learn this flower language, known as floriography. For instance, if someone sends you a bouquet of lupins, hollyhocks, white heather, and ragged robin, they're impressed with your wit and they wish you good luck in everything you do. Aww. If you get hydrangeas, you're "heartless," and if you get delphinium, you're "haughty." A combo of oleander and birdsfoot trefoil says "beware, my revenge." Who knew a beautiful bouquet had such potential to be passive aggressive? It's sort of like a smiley face after an insult.
This trend was said to have started in the 1700s with Lady Mary Wortley Montagu, a famed Victorian letter writer and feminist poet. She drew her inspiration from the Turkish selam [say-lahm], a form of floral language used by harem women to communicate in private. (Kind of like using Pig Latin with your siblings in front of a babysitter.) Flowers and harems both seemed sexy and many upper-class Victorians were fascinated by the "exotic East," so floriography quickly caught on. So much so that nearly 100 flower dictionaries were published in the 18th and 19th centuries. Authors Jane Austen, Emily Dickinson, and Charlotte Bronte all used floral symbolism in their writing.
Sadly, floriography lost its allure during World War I — apparently people had better things to do than research the hidden meaning behind white roses (spoiler: it’s "disinterest in carnality"). However, Duchess Catherine of Cambridge brought some vintage charm to her wedding in 2011 by incorporating flowers that represented love, marriage, and a shared interest in sports, as well as sweet william, meaning gallantry — and a nod to her beloved Prince William. So instead of sending ambiguous emoji the next time you'd like to dissuade a suitor, try delivering yellow roses to say “let’s just be friends.” Hey, at least they'll have flowers.
Most phones nowadays have a “night shift” setting — you know, that thing that makes the screen turn an amber color when the sun goes down in order to help you sleep? That’s the idea, anyway. But according to a new study, that might be all it is: an idea. Night shift screen settings might not actually help you sleep.
People have believed that blue light was keeping us from sleeping for at least a decade. The belief has been that blue light from electronic screens disrupts melatonin production and messes with our sleep cycles. As a result, companies began developing apps that could reduce blue light coming from the screen. The concept was probably some magical thinking. If our screens switch to warmer colors after sunset, maybe we can keep staring at them, not change our habits, and get better sleep! Eventually, Apple and Android phones built a night shift setting right into their operating systems, and now most smartphones have some sort of night mode that claims to reduce blue light and help us sleep.
But here’s the problem. While we had some evidence that short-wavelength light from electronic screens did disrupt our sleep, it wasn’t totally clear that a night-mode setting made it better.
Now, researchers from BYU have tested whether or not night mode can actually help us sleep. For the study, 18- to 24-year-olds spent eight hours in bed wearing an accelerometer to measure their sleep. Some people used their iPhones at night with Apple’s Night Shift on, some used their iPhones without Night Shift on, and some didn’t use their phones at all. Then, the researchers measured how quickly the participants fell asleep, how long they slept, and how well they slept.
The researchers found… not much difference across the three categories. In people who slept around seven hours every night, there was a slight difference in sleep quality based on their phone use. But night mode didn’t make a difference. People who went to sleep without using their phones before bed did sleep better than both those who used night shift and those who didn’t — but only slightly.
Based on this study, it seems like people fall asleep when they’re tired, regardless of whether they use their phones or read a book. If you really want to talk about how phones impact our sleep, the extra stimulation of texting and scrolling and taking in new information probably plays a bigger role than the blue light. So if you really want to fall asleep and stay asleep? Just put your phone away.
Let’s recap what we learned today to wrap up. Starting with
[ad lib optional]
ASHLEY: Today’s writers were Cameron Duke, Anna Todd, and Kelsey Donk.
CODY: Our managing editor is Ashley Hamer.
ASHLEY: Our producer and audio editor is Cody Gough.
CODY: Keep your phone away from your bed! But even if you don’t, you can sleep well tonight knowing that you can join us again tomorrow to learn something new in just a few minutes.
ASHLEY: And until then, stay curious!