genes

Re-think Genes: New Mechanism of Gene Expression Discovered

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If I removed once cell at a time from your body, at what point would you not be you? catiestewart.com

If I removed once cell at a time from your body, at what point would you not be you? catiestewart.com

Researchers are on a seemingly endless quest to discover precisely how DNA and RNA function. A great deal remains a mystery in the field of genetics. In fact up until around one year ago, when scientists captured a photo of DNA, no one knew with absolute certainty what it looked like. The double helix idea was always just a theory.

In a recent ground breaking discovery researchers from the University of Chicago witnessed a never before scene mechanism of gene expression. The researchers found a single gene that encodes two separate proteins from the same sequence of messenger RNA. Let me explain.

Related Article: Women Who Give Birth to Men Have Male DNA in Their Brain for Life

This is from a nucleic acid photoshoot. www.tutorvista.com

This is from a nucleic acid photoshoot. http://www.tutorvista.com

DNA and RNA are similar in that they both contain a genetic blueprint of an organism. They do however differ in several ways. First, RNA comes in three forms: messenger, transfer, and ribosomal.

mRNA (messenger)- The function of mRNA is to carry genetic information from the DNA in the nucleus to the ribosomes of a cell.

tRNA (transfer)- The function of tRNA is to bring the correct amino acid to the ribosomes in the cystosol.

rRNA (ribosomal)- The function of rRNA is to create new ribosomes.

They also differ in that they each incorporate a different sugar molecule in their structure. Also, where DNA has two strands of nucleotides, RNA has only one strand. For the sake of simplicity think of RNA as DNA’s co-conspirator in the continuation of life. In fact, some researchers speculate that life originally depended entirely on self-replicating RNA, rather than the DNA, RNA, and proteins that it depends on to proliferate today. 

Related Article: Deep Storage Project

So, up until this point we thought we had a pretty decent, overall idea of how DNA and RNA functioned. This study just came out of left field and whispered into the collective ear of geneticists around the world: “You know nothing…”

This bundle of RNA and proteins is called a Ribisome.www.itsokaytobesmart.com

This bundle of RNA and proteins is called a Ribisome.www.itsokaytobesmart.com

The study is a big deal because it is the first time that scientists have ever viewed anything even remotely similar. According to Christopher Gomez, MD, PhD, professor and chairman of the Department of Neurology at the University of Chicago, who led the study,

This is the first example of a mechanism in a higher organism in which one gene creates two proteins from the same mRNA transcript, simultaneously. It represents a paradigm shift in our understanding of how genes ultimately encode proteins.

There is a special sequence in the mRNA known as an internal ribosomal entry site (IRES), a site that tells ribosomes to create a protein from the mRNA sequence. The IRES is normally found at the beginning of an RNA sequence, however, in the particular mRNA sequence that the researchers viewed the IRES was in the middle of the sequence, alerting ribosomes to initiate the creation of a second protein from the same sequence.

Related Article: Titan’s Atmosphere Can Make DNA

This is especially exciting news since it creates a beacon of hope for further applicable genetic discovery, not just DNA origami. Just think, we only recently learned in the last couple decades that genetic predisposition isn’t set in stone, and that epigenetics allow us to alter our genetic expression and the genetic expression and predisposition of our children.

You can check your ancestry, health risks, and more through a DNA check that costs $99.

 

Sources:

http://www.newscientist.com/special/unknown-human-genome

https://wondergressive.com/news/first-time-photo-captures-double-helix-structure-of-dna/

http://www.uchospitals.edu/news/2013/20130703-bifunctional-gene.html

https://wondergressive.com/news/women-who-give-birth-to-men-have-male-dna-in-brain-for-life/

http://en.wikipedia.org/wiki/DNA

http://en.wikipedia.org/wiki/RNA

http://sequoyahbiology.webs.com/whatisdnaandrna.htm

http://www.nytimes.com/2013/09/12/science/space/a-far-flung-possibility-for-the-origin-of-life.html?_r=1&

https://wondergressive.com/news/deep-storage-project/

https://wondergressive.com/news/titans-atmosphere-can-make-dna/

https://wondergressive.com/news/dna-origami-the-art-of-folding-dna/

https://wondergressive.com/news/epigenetics-the-key-to-overcoming-genetic-predisposition

https://wondergressive.com/news/epigenetics-and-altering-your-dna/

https://wondergressive.com/news/dna-ancestry-23andme/

Did You Know That Certain Plants Do Division?

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Plants Do Division

Plants Do Division http://news.jic.ac.uk/

 

I thought that only humans can do arithmetic, but plants do division as well. I guess a brain with a neocortex is not required. New research shows that arabidopsis plants perform an arithmetic feat to know how to distribute stored energy during the night when there is no light, preventing starvation.

Plants get their energy from light through a process called photosynthesis. This involves breaking down carbon dioxide compounds into sugars. And we all know what awesome byproduct that gives us; oxygen! So during the day they store sugars, and during the night plants do division in order to distribute the sugars at a steady rate. This insight comes from new research done by the scientists at the John Innes Centre and found through the open access journal eLife.

It is vital that plants do division in order to be able to grow properly. Learning more about this process has some implications, such as possible plant hacking in order to achieve higher crop yields. This is already being done with GMOs.

Plants do division during night time. There are certain “mechanisms” in the leaves that measure how much of the starch is stored and how much time will pass until the sun rises. Plants also have a sort of an internal “biological clock” which allows them to guess when dawn will come. There are three clock genes that work together like a seesaw. When dawn comes, these genes instruct the plant to make two proteins, CCA1 and LHY. These proteins tell the plant that it is daytime. During the day these are destroyed, which allows for the third protein, TOC1, to be made. This tells the plant that it is night time. That last protein also tells the plant that it’s time to make the first two, so the whole process cycles again.

According to Professor Alison Smith,

the calculations are so precise so that plants prevent starvation but also make most efficient use of their food.

Using up the starch too fast will induce starvation, while using it up too slow will waste the unused starch. Scientists predict that there are two molecules that encode the information about how much starch is stored at a given time and time until dawn breaks. Let’s call these molecules S and T for the time being. The rate at which starch is consumed is set by the ratio of S molecules to T molecules. Because a ratio is actually a fancy way to say division, scientists are confident in the claim that plants are division experts.

Sources:

http://elife.elifesciences.org/content/2/e00669

http://news.jic.ac.uk/2013/06/plants-do-sums-to-get-through-the-night/

http://arabidopsis.info/InfoPages?template=arabidopsis;web_section=arabidopsis

http://www.plantsci.cam.ac.uk/research/webb/plantTime/clock.html

Aging Process Is Similar to Replicating CDs: Story of Telomeres

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Why do we age? What is it that makes us age and grow saggy? How can we bring our youthful glow into adulthood and beyond? These are the questions that most women ask themselves. Joking, scientists and men alike ask the same questions. And you might find your answer in telomeres.

 

Brief Intro to Telomeres

 

Human cells divide at an average of 50-60 times in one lifespan. Every time they divide, the cell’s DNA has to be replicated. That way, a new chromosome can form and be used in the newly duplicated cell. However every time a cell duplicates, it comes at a cost. That is, the chromosomes get shorter and shorter. If they get short enough, the chromosomes can have their twining undone and our genetic data gets corrupted. Eventually, that cell dies.

Fortunately, chromosomes are like shoelaces with plastic caps. These plastic caps are what keep the shoelaces from getting undone. Chromosomes have their own plastic caps too. They are called telomeres. They are the extra DNA strands that a chromosome can afford to lose. They are what keep chromosomes from getting corrupt. So why are we not immortal? This is what an article from the University of Utah has to say about telomeres and division:

Yet, each time a cell divides, the telomeres get shorter. When they get too short, the cell no longer can divide and becomes inactive or “senescent” or dies. This process is associated with aging, cancer and a higher risk of death. So telomeres also have been compared with a bomb fuse.

 

They help to preserve genetic data when cells replicate in order to have fully functional healthy cells. RNA molecules are necessary in the process of copying DNA strands. Telomeres get shorter each time because these small RNA pieces need room on top of newly formed chromosomes.

Without telomeres, the ends of chromosomes would look like broken DNA, and the cell would try to fix something that wasn’t broken. That also would make them stop dividing and eventually die.

Telomerase, Cancer, and Aging

 

So is there something that keeps telomeres from disappearing? Actually there is an enzyme called telomerase. They fit on top of telomeres and are more prevalent in the younger years, however they also eventually disappear.

This is not the case for cancerous cells. Cancer cells activate the telomerase enzymes once the telomeres get dangerously short. This keeps the cancer cell’s DNA intact and allows them to multiply like mad dogs. In fact, measuring telomerase may be a new way to detect new cancer threats. If we learn how to stop telomerase from being activated, we may be able to make cancer cells experience aging just like healthy cells.

 In one experiment, researchers blocked telomerase activity in human breast and prostate cancer cells growing in the laboratory, prompting the tumor cells to die. But there are risks.

Shorter telomeres are related to shorter lives. Unfortunately, there is no strong evidence yet that shows that telomerase can make cells immortal and prevent aging. There is also no strong evidence that raising telomerase levels would also trigger cancerous cells to form.

Laboratory tests have shown though that telomerase was able to keep human cells divide far beyond the average limit without becoming cancerous. If researched further, we can have a future where human cells can be mass produced for transplantation, especially in key roles such as cells that produce insulin for diabetes patients.

Sources:

Genetic Science Learning Center. “Are Telomeres the Key to Aging and Cancer?.” Learn.Genetics 12 March 2013 http://learn.genetics.utah.edu/content/begin/traits/telomeres/

 

Tetrachromacy: “Super Vision” Genes

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As humans, most of us share more things in common than we realize—one of which includes our ability to perceive the world around us. With the exception of some visually impaired individuals and a few others with known colorblindnesses, most of us are what scientists call “trichromats.” Veronique Greenwood of DiscoverMagazine.com said it best:

Our powers of color vision derive from cells in our eyes called cones, three types in all, each triggered by different wavelengths of light. Every moment our eyes are open, those three flavors of cone fire off messages to the brain. The brain then combines the signals to produce the sensation we call color.

A limited amount of research (the first known scientific reference was from a 1948 paper that briefly touched on the topic) has been done into what we might consider the opposite of colorblindness, referred to in the science world as dichromacy: tetrachromacy. In layman’s term’s, this basically boils down to some women being able to see more colors than the rest of us. Super vision! In scientific terms, it actually makes sense and doesn’t sound so far fetched.

Colorblindness is a trait that affects more men than women. Where regular, trichromatic humans have three cones in their eyes that perceive color, dichromats have two functional cones and one with a mutation. Since colorblindness is genetic, the women in families of colorblind men also carry this gene—yet they generally don’t suffer from its affects. They have three functional cones plus the mutant one. This then allows them to perceive a wider breadth of colors then those with only three healthy, functioning cones.

Now, none of this means that tetrachromats are discovering amazing new colors in every mundane object you see like some perpetual, never-ending acid trip. DamnInteresting.com’s Cynthia Wood states that:

If the modified color receptor is sensitive to wavelengths very close to a normal receptor, then the tetrachromat would merely have slightly better color-vision. The further apart the wavelength sensitivities of the receptors, the more the tetrachromat’s vision would differ from the norm.

This is all still extremely new, and not enough research has gone into it yet. One paper insists that we’re all tetrachromats, but not all of us can tap into our tetrachrome abilities:

There is now excellent data showing the architecture of the human visual system uses and supports photoreceptors containing four distinctly different spectral absorbers (chromophores).

Pretty interesting stuff!

 

Sources:

http://discovermagazine.com/2012/jul-aug/06-humans-with-super-human-vision#.UaRihdKnfrt

http://www.sciencedirect.com/science/article/pii/0031891448900214

http://www.damninteresting.com/a-life-more-colorful/

http://www.neuronresearch.net/vision/files/tetrachromat.htm

 

The Most Evil Profession in the World is Also One of the OIdest

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A very early form of human dentistry took place at least 6,500 years ago. Researchers have discovered that early dentists used beeswax to fill cavities and treat tooth aches.

Dr Federico Bernardini states that:

“This finding is perhaps the most ancient evidence of pre-historic dentistry in Europe and the earliest known direct example of therapeutic-palliative dental filling so far.”

Other researchers have also dated tooth drilling to at least 9000 years old.  Although it is unclear why the teeth were drilled, it may very well have been to alleviate pain.

No wonder we are so afraid of going to the dentist.  The fear has been imprinted onto our genetic make up over the course of 1000’s of generations!

Dentistry: A Feared Profession, One of World’s Oldest

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A very early form of human dentistry took place at least 6,500 years ago. Researchers have discovered that early dentists used beeswax to fill cavities and treat tooth aches.

Dr Federico Bernardini states that:

“This finding is perhaps the most ancient evidence of pre-historic dentistry in Europe and the earliest known direct example of therapeutic-palliative dental filling so far.”

Other researchers have also dated tooth drilling to at least 9000 years old.  Although it is unclear why the teeth were drilled, it may very well have been to alleviate pain.

No wonder we are so afraid of going to the dentist.  The fear has been imprinted onto our genetic make up over the course of 1000’s of generations!

 

 

 

Sources:

The Daily Mail- Beeswax filling reveals human dentistry began 6,500 years ago

Wired- 9,000 Year Old Dentistry

Epigenetics and Altering Your DNA