Posts tagged DNA
rhamphotheca:

For such tiny animals, Syllidae really get around. 
These polychaete worms, most only a few millimeters long, are found from the intertidal to the deep sea. The over 200 species of Syllids, and potentially many more not yet recognized, are keeping some molecular biologists very busy. 133 species from 5 continents have DNA barcodes already, and our colleagues at the Moorea Biocode project just keep finding more, just waiting to be identified, or classified as new species. More Syllids from Moorea here.
(via: Encyclopedia of Life)

rhamphotheca:

For such tiny animals, Syllidae really get around.

These polychaete worms, most only a few millimeters long, are found from the intertidal to the deep sea. The over 200 species of Syllids, and potentially many more not yet recognized, are keeping some molecular biologists very busy. 133 species from 5 continents have DNA barcodes already, and our colleagues at the Moorea Biocode project just keep finding more, just waiting to be identified, or classified as new species.

More Syllids from Moorea here.

(via: Encyclopedia of Life)

(via ichthyologist)

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Ancient Mars Had Component Key to Life, Meteorite Reveals
At a time when life as we know it was just getting its start on Earth, Martian clay may have harbored a key component for one of life’s molecular building blocks, researchers say.
Boron found in a Martian meteorite suggests the Red Planet may once have had the right chemistry to give rise to RNA, according to a new study.
“In early life RNA is thought to have been the informational precursor to DNA,” study researcher James Stephenson, an evolutionary biologist, said in a statement.
Billions of years ago, RNA may have been the first molecule to program information and pass it on to the next generation. Today, that task is DNA’s domain. RNA, meanwhile, is responsible for carrying genetic information from DNA to proteins. Researchers believe the RNA sugar component, ribose, relies on borates (the oxidized form of boron) to form spontaneously.
“Borates may have been important for the origin of life on Earth because they can stabilize ribose, a crucial component of RNA,” added Stephenson, who is a postdoctoral fellow at the University of Hawaii at Manoa NASA Astrobiology Institute (UHNAI).
Read more: [x]
Image: Electron microscope image showing the 700-million-year-old Martian clay veins containing boron. CREDIT: UHNAI 

Ancient Mars Had Component Key to Life, Meteorite Reveals

At a time when life as we know it was just getting its start on Earth, Martian clay may have harbored a key component for one of life’s molecular building blocks, researchers say.

Boron found in a Martian meteorite suggests the Red Planet may once have had the right chemistry to give rise to RNA, according to a new study.

“In early life RNA is thought to have been the informational precursor to DNA,” study researcher James Stephenson, an evolutionary biologist, said in a statement.

Billions of years ago, RNA may have been the first molecule to program information and pass it on to the next generation. Today, that task is DNA’s domain. RNA, meanwhile, is responsible for carrying genetic information from DNA to proteins. Researchers believe the RNA sugar component, ribose, relies on borates (the oxidized form of boron) to form spontaneously.

“Borates may have been important for the origin of life on Earth because they can stabilize ribose, a crucial component of RNA,” added Stephenson, who is a postdoctoral fellow at the University of Hawaii at Manoa NASA Astrobiology Institute (UHNAI).

Read more: [x]

Image: Electron microscope image showing the 700-million-year-old Martian clay veins containing boron. CREDIT: UHNAI 

(via distant-traveller)

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Junk DNA
Since Crick and Watson’s historic discovery of DNA, our investigation into coding DNA has gone a long way towards unravelling the key to life—but coding DNA only makes up just a few percent of the human genome. The rest is termed “Junk DNA” or “Non-coding DNA” because it doesn’t appear to have any function. However, new research suggests that this Junk DNA might actually play an important role in evolutionary history. Huge “ultraconserved” sections of it have remained the same for millions of years and are identical in many organisms—when you hear that humans and chimps share 98% of DNA, it’s mostly due to this. Increasing evidence suggests that Junk DNA influences coding DNA by acting as a kind of genetic “switch” in gene regulation, and it may also play a role in inheritance, but our knowledge is incomplete. If Junk DNA were really junk, then its sequence of “syllables” should be completely random, but it’s not random—leading scientists to believe it contains some kind of coded information. It’s been suggested that specific repetitive patterns are associated with susceptibility to cancer and other diseases, so understanding Junk DNA might be the key to understanding, diagnosing and curing disease.

Junk DNA

Since Crick and Watson’s historic discovery of DNA, our investigation into coding DNA has gone a long way towards unravelling the key to life—but coding DNA only makes up just a few percent of the human genome. The rest is termed “Junk DNA” or “Non-coding DNA” because it doesn’t appear to have any function. However, new research suggests that this Junk DNA might actually play an important role in evolutionary history. Huge “ultraconserved” sections of it have remained the same for millions of years and are identical in many organisms—when you hear that humans and chimps share 98% of DNA, it’s mostly due to this. Increasing evidence suggests that Junk DNA influences coding DNA by acting as a kind of genetic “switch” in gene regulation, and it may also play a role in inheritance, but our knowledge is incomplete. If Junk DNA were really junk, then its sequence of “syllables” should be completely random, but it’s not random—leading scientists to believe it contains some kind of coded information. It’s been suggested that specific repetitive patterns are associated with susceptibility to cancer and other diseases, so understanding Junk DNA might be the key to understanding, diagnosing and curing disease.

(Source: sciencesoup, via shychemist)

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laboratoryequipment:

New Instrument “Slams” Cells to Diagnose DiseaseIf you throw a rubber balloon filled with water against a wall, it will spread out and deform on impact, while the same balloon filled with honey, which is more viscous, will deform much less. If the balloon’s elastic rubber was stiffer, an even smaller change in shape would be observed. By simply analyzing how much a balloon changes shape upon hitting a wall, you can uncover information about its physical properties.Although cells are not simple sacks of fluid, they also contain viscous and elastic properties related to the membranes that surround them; their internal structural elements, such as organelles; and the packed DNA arrangement in their nuclei. Because variations in these properties can provide information about cells’ state of activity and can be indicative of diseases such as cancer, they are important to measure.Read more: http://www.laboratoryequipment.com/news-Slammed-Cells-Diagnose-Disease-050212.aspx

laboratoryequipment:

New Instrument “Slams” Cells to Diagnose Disease

If you throw a rubber balloon filled with water against a wall, it will spread out and deform on impact, while the same balloon filled with honey, which is more viscous, will deform much less. If the balloon’s elastic rubber was stiffer, an even smaller change in shape would be observed. By simply analyzing how much a balloon changes shape upon hitting a wall, you can uncover information about its physical properties.

Although cells are not simple sacks of fluid, they also contain viscous and elastic properties related to the membranes that surround them; their internal structural elements, such as organelles; and the packed DNA arrangement in their nuclei. Because variations in these properties can provide information about cells’ state of activity and can be indicative of diseases such as cancer, they are important to measure.

Read more: http://www.laboratoryequipment.com/news-Slammed-Cells-Diagnose-Disease-050212.aspx

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k-rin:

Artwork of a molecular model of a DNA nucleosome, the repeating unit used to package DNA (genetic material) inside the nucleus of cells. The spiral helix of DNA (red, blue) is seen coiled around a core of histone proteins (centre, multicoloured) and each set of two DNA loops around a histone core is known as a nucleosome.

k-rin:

Artwork of a molecular model of a DNA nucleosome, the repeating unit used to package DNA (genetic material) inside the nucleus of cells. The spiral helix of DNA (red, blue) is seen coiled around a core of histone proteins (centre, multicoloured) and each set of two DNA loops around a histone core is known as a nucleosome.

(via k-rin-deactivated20120525)

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Genetic analyses of individuals buried in funereal monuments near a volcano in southern Peru have revealed the family relationships and burial traditions of ancient Peruvians that lived before Christopher Columbus sailed to the Americas.

The ancient Peruvians buried their dead in “chullpas,” structures resembling vertical tombs, which can be up to 6.5 feet (2 meters) high. Researchers hadn’t known how the individuals buried within one chullpa were related.

Families were organized into “ayllu,” a group of relatives that shared common land and responsibilities. Historians think that men retained the ancestral land, and they traded their sisters for wives, in a sort of “sister exchange.”

Ancient genes

In the new study, researchers from the University of Warsaw, in collaboration with Universidad Catolica de Santa Maria, retrieved and analyzed genomic sequences of 41 individuals buried in six chullpas located 13,000 feet (4,000 meters) up the side of the Cora Cora Mountain in southern Peru. Though the site had been looted, the remains were well preserved by the cold and the dryness of the land, and the researchers were able to isolate DNA from the bones and teeth of 27 individuals.

They looked at the nuclear DNA, which is our main genetic code and is inherited from both parents, along with the maternally inherited mitochondrial genome (which is separate from the nuclear genome, and runs the cell’s energy factory, the mitochondria); they also analyzed genetic sequences from the Y chromosome, which is inherited from the father and determines that an individual is male.

They used this information to identify the sex of each individual and compare their genes in order to figure out the family relationships between them. They also compared their DNA with a sample of 700 individuals from contemporary Amerindian populations from South America.

The researchers found that the people from the chullpas were genetically similar to modern Andean populations from Peruvian regions like Puno, San Martin, Ancash and Yungay. European colonization of the area didn’t seem to have an impact on the genetics of the people living in the region.

Family connections

The researchers also found that the family connections between individuals were the strongest within each chullpa, and most likely a given ayllu buried its members in one chullpa for many generations.

Two of the chullpas contained sets of males with identical Y chromosomes, which meant these were two groups of directly related males (fathers, sons, brothers) of several generations buried together.This finding matched the currently accepted male-dominated ayllu theory.

There was an outlier, though. In a third chullpa three different male lineages were found. Comparison of the maternal DNA of these males suggests that two of the males had the same mother but different fathers, and the third male was related to one of the mothers (but not the fathers), probably a half brother.

The researchers explain this oddity in their paper, published online April 23 in the journal BMC Genetics, by saying that “the rules governing marriages and social organization were an idealization, and we cannot exclude a situation that was intentionally or unintentionally violated in some situations.”

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fuckyeahmolecularbiology:

Ancient Viral DNA in the Human Genome
Traces of ancient viruses, which infected our ancestors millions of years ago, are more widespread throughout our modern-day genomes than was previously thought.
The new research sheds light on the origins of a large proportion of our genetic material, much of which is still not understood. Only about 1.5% of human genes code for a useful protein product, that we’ve discovered; half of the rest is labeled “junk DNA” - although new research indicates it has a variety of purposes - while the other half was introduced by viruses or parasites, like the ancient ones studied here.
The senior author on the study (published in the Proceedings of National Academy of Sciences), Dr. Robert Belshaw from Oxford University’s Zoology Department, said: “This is the story of an epidemic within every animal’s genome, a story which has been going on for 100 million years and which continues today.
“Much of the dark matter in our genome plays by its own rules, in the same way as an epidemic of an infectious disease but operating over millions of years.
Learning the rules of this ancient game will help us understand their role in health and disease.”
Not only do these viruses exist within our genomes, but some of are even helpful, Dr. Belshaw insists. Protein syncytin, for example - derived from a virus - helps develop the human placenta.
The study believes that unlocking the secrets of these viruses is essential to understanding the full complexity of the human genome.
Image: SEM image of Influenza A virus.

fuckyeahmolecularbiology:

Ancient Viral DNA in the Human Genome

Traces of ancient viruses, which infected our ancestors millions of years ago, are more widespread throughout our modern-day genomes than was previously thought.

The new research sheds light on the origins of a large proportion of our genetic material, much of which is still not understood. Only about 1.5% of human genes code for a useful protein product, that we’ve discovered; half of the rest is labeled “junk DNA” - although new research indicates it has a variety of purposes - while the other half was introduced by viruses or parasites, like the ancient ones studied here.

The senior author on the study (published in the Proceedings of National Academy of Sciences), Dr. Robert Belshaw from Oxford University’s Zoology Department, said: “This is the story of an epidemic within every animal’s genome, a story which has been going on for 100 million years and which continues today.

“Much of the dark matter in our genome plays by its own rules, in the same way as an epidemic of an infectious disease but operating over millions of years.

Learning the rules of this ancient game will help us understand their role in health and disease.”

Not only do these viruses exist within our genomes, but some of are even helpful, Dr. Belshaw insists. Protein syncytin, for example - derived from a virus - helps develop the human placenta.

The study believes that unlocking the secrets of these viruses is essential to understanding the full complexity of the human genome.

Image: SEM image of Influenza A virus.

(Source: amolecularmatter)

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