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Move Over, Double Helix: A New Form of DNA Has Just Been Discovered

This is the first time it's ever been seen in a living cell.

When we learn about human genetics in high school biology class, one of the most basic things we learn about is the DNA double helix, the twisting ladder-shaped structure that holds our genetic code. But scientists have long suspected there’s another type of DNA that looks quite different from the famous Watson-Crick model. They theorized that it’s knot-shaped, though they’d never observed it in a living cell … until now.

In a paper published Monday in the journal Nature Chemistry, a team of researchers describe their evidence for the existence and possible function of this knotty DNA, called “human telomeric i-motif.” To identify the i-motif DNA, the researchers, led by first author Mahdi Zeraati a Ph.D. student at the Garvan Institute of Medical Research in Sydney, Australia, developed an antibody that would bind to the elusive DNA and allow them to capture images of it with the help of immunofluorescent staining. They suspect that the i-shaped DNA, which had previously only been observed in lab conditions very different from those in a living cell, regulates some genetic functions.

Researchers observed the i-motif DNA blink in and out, suggesting that it's regulating a cell function.

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“We provide the first direct evidence for the presence of i-motif structures in the nuclei of human cells,” the study’s authors write, as this is the first time anyone has observed the i-motif DNA, except for in lab conditions that don’t represent actual conditions in a living cell. The fact that scientists finally observed this different form of DNA in human cells is a pretty big deal, but it’s actually even more than just a different shape. It seems to play by different rules than double-helix DNA, too. It employs nucleotides — the basic A, G, T, and C units that compose DNA — a lot differently than helical DNA does.

“The i-motif is a four-stranded ‘knot’ of DNA,” Marcel Dinger, Ph.D., an associate professor at Garvan and one of the study’s authors, explained in a statement released Monday. “In the knot structure, C letters on the same strand of DNA bind to each other — so this is very different from a double helix, where ‘letters’ on opposite strands recognize each other, and where Cs bind to Gs.”

This paper represents a very early stage of figuring out what the i-motif DNA actually does in human cells. One idea the team has is that the i-motif DNA regulates some cell function, as indicated by the fact that it seemed to blink on and off in their observations. “We think the coming and going of the i-motifs is a clue to what they do,” said Zeraati. “It seems likely that they are there to help switch genes on or off, and to affect whether a gene is actively read or not.”

Future studies of the i-motif DNA will be necessary to figure out exactly what its role is, but this paper sets the groundwork for observing it, which is a significant step toward unlocking its mysteries.

Prime Day 2019: 3 Bonkers Gaming Set-Ups You Can Make Using Amazon Deals

Three set-ups for three types of gamers.

Amazon Prime Day 2019 is just around the corner for its fifth year of summertime deals. The savings event will last kick off on July 15 at 3 a.m. Eastern and slash prices on everything from high-powered PC rigs to cutting-edge consoles, everything a gamer needs to take their gaming setup to the next level.

Prime Day 2019: 3 Deals to Make a Face-Melting Home Entertainment System

Prime Day could be the ideal chance to get a system that impresses.

Prime Day is almost here, and with it, a chance to level-up your home entertainment system. Whether it’s a new streaming stick, a high-end television, or a quantum dot screen, Amazon has a number of offers for interested buyers so you can re-binge Thrones in style.

The 48-hour Prime Day event will be the longest ever, and is scheduled to start at 3 a.m. Eastern time on July 15. Subscribers to Amazon’s Prime service will also be able to ask their Echo device, “Alexa, what are my Prime Day deals?” Members will also have access to a selection of early device deals at 3 p.m. Eastern time on July 14.

Amazon Prime Day 2019: Best Tablet Deals, Headphones, and "On-the-Go" Tech

From headphones to tablets, we've got you covered. 

E-commerce holidays are forever proliferating. Black Friday may still be the largest, affecting retailers all over the country. But few besides it come close to the scale and reach of one of the biggest retail days of them all, Amazon Prime Day.

Amazon’s huge annual two day sale will take place on July 15 and 16 this year, bringing with it a slew of deals that can be a bit overwhelming if you don’t know what to look for. That’s why we’re here though, to sort through it so you don’t have to.

Amazon Prime Day: Look for These Awesome Smart Home Items

Keep your eyes peels on these items for deep discounts.

Now that we’re officially in the month of July, you can start to get excited about Amazon’s upcoming Prime Days. While there’s really no telling just how great the deals will be (besides comparing to the ones from last year), there’s a good chance that there will be several great deals on smart home items. Amazon itself make quite a few devices, so it would only make sense to see some steep discounts on other items in hopes that you’ll further delve into its ecosystem. Keep your eyes on these awesome smart home items when Amazon’s Prime Days arrive on July 15th-16th.