DNA Replication Has Been Filmed For The First Time

Reshared post from +Corina Marinescu

DNA Replication Has Been Filmed For The First Time
“Here’s proof of how far we’ve come in science – in a world-first, researchers have recorded up-close footage of a single DNA molecule replicating itself, and it’s raising questions about how we assumed the process played out.The real-time footage has revealed that this fundamental part of life incorporates an unexpected amount of ‘randomness’, and it could force a major rethink into how genetic replication occurs without mutations.”

HOW IT WORKS:
“The DNA double helix consists of two intertwining strands of genetic material made up of four different bases – guanine, thymine, cytosine, and adenine (G, T, C and A).Replication occurs when an enzyme called helicase unwinds and unzips the double helix into two single strands.A second enzyme called primase attaches a 'primer’ to each of these unravelled strands, and a third enzyme called DNA polymerase attaches at this primer, and adds additional bases to form a whole new double helix.”

WHY THIS IS WEIRD AND NOT WHAT WE EXPECTED:
“The fact that double helices are formed from two stands running in opposite directions means that one of these strands is known as the 'leading strand’, which winds around first, and the other is the 'lagging strand’, which follows the leader.The new genetic material that’s attached to each one during the replication process is an exact match to what was on its original partner.So as the leading strand detaches, the enzymes add bases that are identical to those on the original lagging stand, and as the lagging strand detaches, we get material that’s identical to the original leading strand.

Scientists have long assumed that the DNA polymerases on the leading and lagging strands somehow coordinate with each other throughout the replication process, so that one does not get ahead of the other during the unraveling process and cause mutations. But this new footage reveals that there’s no coordination at play here at all – somehow, each strand acts independently of the other, and still results in a perfect match each time.“

Source & further reading:
https://www.eurekalert.org/pub_releases/2017-06/uoc–vio061317.php

Journal article:
http://www.cell.com/cell/fulltext/S0092-8674(17)30634-7?_returnURL=http%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0092867417306347%3Fshowall%3Dtrue

Gif:
Each glowing strand is a piece of double helix growing by replication at the left-hand end. They move at different speeds and stop and start. Dark gaps in the line are single-stranded DNA where one polymerase failed to attach (the fluorescent dye only binds double-stranded DNA).

Some surprises come out of being able to observe replication directly. For example, the two polymerases involved in replication (one for each strand) aren't coordinated. They stop and start at random, but overall they move at the same average speed, so everything works out. This stochastic model is quite different from a smooth-running, coordinated machine usually imagined.

CREDIT: James Graham, UC Davis

#DNA #research #biology #molecularbiology #cells #science

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Still Think Humans are the Most Intelligent Animals?

Reshared post from +Corina Marinescu

Still Think Humans are the Most Intelligent Animals?
In the book The Dynamic Human, it is argued by a group of researchers from the University of Adelaide that humans aren’t the brightest crayons in the box. Co-author and research fellow, Dr. Arthur Saniotis, said “For millennia, all kinds of authorities — from religion to eminent scholars — have been repeating the same idea ad nauseam, that humans are exceptional by virtue that they are the smartest in the animal kingdom. However, science tells us that animals can have cognitive faculties that are superior to human beings.”

How can this be?! No other animal can think or communicate like a human, so clearly no other species can match our intelligence!
Well, while humans, as a species, are pretty smart, it’s impossible for us to claim the title of “most intelligent” species. After all, we still have many questions left to answer about our own brains, before we can truly compare them to that of another organism.

While primates are often used in studies on animal intelligence because of their similarities to humans, cetaceans are frequently used as research subjects as well. Looking at the brain of a cetacean, it is clear that perhaps dolphins and whales are much more complex than previously thought.

According to a comparison of cetacean to primate brains from Michigan State University, “They have the distinct advantage over us in that their primary sense is the same as their primary means of communication, both are auditory. With primates, the primary sense is visual and the primary means of communication is auditory.”
Communication is so great in cetaceans that there is a strong possibility they are able to project (yes … literally project) an “auditory image” that replicates a sonar message they may receive.

The process is a bit confusing, but MSU describes it in this circumstance: “So a dolphin wishing to convey the image of a fish to another dolphin can literally send the image of a fish to the other animal. The equivalent of this in humans would be the ability to create instantaneous holographic pictures to convey images to other people.”

If they are in fact able to do this, there would have to be a natural tendency to break down stylized and abstracted images into words. Meaning, cetaceans, like people, use a series of signifiers to discern the exact objects they want to communicate about. We might say “tree” and think of a picture of a tree in our minds, but cetaceans can skip this step by simply projecting the image to other cetaceans.

Not fascinating enough? Well did you know that, with several sound producing organs, cetaceans are capable of conveying and receiving “20 times the amount of information as we can with our hearing”? This surpasses the amount of information we can perceive based on vision (a human’s primary sense).

Interesting article via OneGreenPlanet:
http://www.onegreenplanet.org/animalsandnature/human-intelligence-versus-whales-and-dolphins/

PR:
http://www.adelaide.edu.au/news/news67182.html

#research   #evolution   #humanbrain   #intelligence   #cetaceans  

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So, I've postulated that micro-organisms may in fact not be individual beings…

So, I've postulated that micro-organisms may in fact not be individual beings but collections of them may form larger, invisible beings that differ from us in that their building blocks are spaced further out. A theory on Jinn.

Reshared post from +Corina Marinescu

Biologists Discover Bacteria Communicate Like Neurons in the Brain
Biologists at UC San Diego have discovered that bacteria —often viewed as lowly, solitary creatures — are actually quite sophisticated in their social interactions and communicate with one another through similar electrical signaling mechanisms as neurons in the human brain.

In a study published in Nature, the scientists detail the manner by which bacteria living in communities communicate with one another electrically through proteins called “ion channels.”

“Our discovery not only changes the way we think about bacteria, but also how we think about our brain,” said Gürol Süel, an associate professor of molecular biology at UC San Diego who headed the research project. “All of our senses, behavior and intelligence emerge from electrical communications among neurons in the brain mediated by ion channels. Now we find that bacteria use similar ion channels to communicate and resolve metabolic stress. Our discovery suggests that neurological disorders that are triggered by metabolic stress may have ancient bacterial origins, and could thus provide a new perspective on how to treat such conditions.”

Paper:
http://www.nature.com/nature/journal/v527/n7576/full/nature15709.html

PR:
http://ucsdnews.ucsd.edu/pressrelease/biologists_discover_bacteria_communicate_like_neurons_in_the_brain

Image: Bacteria within a biofilm (in background and close up in right hemisphere inset) have similar electrical signaling mechanisms as neurons in the human brain.
Credit: Suel lab

#neuroscience   #brain   #bacteria   #research  

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