DNA – Page 2 – GOLLYGEE!

01.25.2013

dna data storage

DNA, RNA and their bases

In the January 23rd edition of Nature a team of scientists report using DNA to store poems, a picture and a recorded speech. From Science News:

Led by Nick Goldman, researchers from the European Bioinformatics Institute in England began by converting the five files into bits (technically, “trits” — they used a triplet code comprising zero, one and two). Then they translated that code into one made of As, Cs, Gs and Ts, the “letters” of DNA. So TAGAT replaces the “T” that begins line two of Shakespeare’s sonnet 18: “Thou art more lovely and more temperate.” The team also incorporated a way to index the data — sort of a DNA version of the Dewey Decimal System — and an error correction code to keep the data clean.

Then the researchers sent their code to the instrumentation company Agilent Technologies in Santa Clara, Calif. There scientists read the code and used it to build millions upon millions of DNA molecules, which they sent back to the researchers via FedEx in a test tube inside a cardboard box.

When the test tube, about the size of a pinkie finger, arrived, Goldman and his colleagues sequenced the DNA, the same way researchers read the DNA of organisms, reconstructing the original files. The translation from data to DNA and back was free of errors, says Goldman.

DNA storage offers the potential of holding vastly more data in a smaller amount of space. It might also potentially be cheaper as the cost of DNA synthesis and sequencing continues to become less costly.

09.05.2012

“junk” dna not so junky

Junk DNA

From the New York Times:

The human genome is packed with at least four million gene switches that reside in bits of DNA that once were dismissed as “junk” but that turn out to play critical roles in controlling how cells, organs and other tissues behave. The discovery, considered a major medical and scientific breakthrough, has enormous implications for human health because many complex diseases appear to be caused by tiny changes in hundreds of gene switches.

The findings are the fruit of an immense federal project, involving 440 scientists from 32 labs around the world. As they delved into the “junk” — parts of the DNA that are not actual genes containing instructions for proteins — they discovered it is not junk at all. At least 80 percent of it is active and needed.

The result is an annotated road map of much of this DNA, noting what it is doing and how. It includes the system of switches that, acting like dimmer switches for lights, control which genes are used in a cell and when they are used, and determine, for instance, whether a cell becomes a liver cell or a neuron.

More here.

04.20.2012

DNA, RNA, XNA

A DNA helix

DNA & RNA genetic information to be stored and propagated through the generations. Now researchers have created new molecules called XNAs by replacing the sugar molecules on the DNA or RNA phosphate backbone with an analog. From Science News:

The researchers, led by Philipp Holliger of the MRC Laboratory of Molecular Biology in Cambridge, England, did make completely new genetic molecules. In the backbone of every DNA molecule there are repeating units of deoxyribose sugar, in the RNA backbone it’s ribose sugar. Instead of those sugars, the various XNAs have different molecules in their backbones: a five-carbon sugar called arabinose in ANA, the ringed structure anhydrohexitol in HNA, and threose, a four-carbon sugar in TNA. The scientists also created XNA molecules called FANA (2´-fluoroarabinose), CeNA (cyclohexene) and LNA (“locked” ribose analog).

In a second bioengineering feat, the researchers created special enzymes for the XNAs so that they could evolve. This requires enzymes that can “read” the order of molecular components in a strand of XNA and use that information to build a complementary strand of DNA. Working with an enzyme from a sulfur-loving microbe, the team selected for versions that could “read” each of the XNAs. The researchers also made enzymes that could do the reverse: read DNA and use that information to build XNA.

Because the XNAs can’t copy themselves without help from DNA, it’s not truly synthetic life, says Joyce. But the molecules do undergo good old-fashioned evolution. With HNA, for example, the researchers created a random population of HNA molecules, then exposed them to a bunch of target molecules (such as proteins or RNA) for the HNA to attach to. Most of the HNAs didn’t do diddly-squat, but a fraction were slightly better at connecting to the target molecules.

More here and here.

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Tag: DNA (page 2 of 3)

dna data storage

“junk” dna not so junky

DNA, RNA, XNA