DNA – Extra Than Simply Genetic Materials
As is extensively identified, DNA base pairing (Determine 1) gives the chemical basis for the world of genetics. DNA is the hereditary materials in people and virtually all different organisms. It accommodates the directions wanted for an organism to develop, survive and reproduce . This establishes it as the first constructing block of biology. DNA is talked about, principally, within the context of this function. Nevertheless, its use as the premise for the creation of recent supplies is gaining an rising degree of traction . DNA and protein-based supplies have huge potential as chemical instruments for the synthesis of extra superior methods. This finally results in the event of improved diagnostic and therapeutic methods. It’s this side of DNA that Dr. Devleena Samanta from the College of Texas, Austin, explores on the Samanta Laboratory.
Determine 1: Particular base pairing in DNA
A base pair is a connection between nitrogenous bases that helps maintain the 2 strands of DNA collectively. This connection primarily creates the rungs of the ladder within the DNA molecule. There are particular patterns for a way the bases match collectively, known as Chargaff’s guidelines. These guidelines clarify that adenine all the time pairs with thymine (A with T) and cytosine pairs with guanine (C with G).
One in every of Dr. Devleena’s analysis initiatives includes the expertise generally known as ‘DNA origami’, a more moderen method that makes use of DNA for the synthesis of nanoparticles. Think about the double-helix construction usually related to DNA. Heating it ends in the separation of the 2 DNA strands. The only strands thus obtained are utilised within the DNA origami methodology . “Origami” is the Japanese artwork of paper folding, with the aim being to fold a flat sheet of paper right into a completed sculpture. Equally, these lengthy strands of DNA are folded into a posh construction of “staple strands” which every have 200–300 nucleotides* .
The underlying precept behind DNA origami is predicated on a easy rule: base-pair complementarity. Typically, hydrogen bonds in DNA that pair the bases adenine and thymine (A to T), and cytosine and guanine (C to G) enable complementary DNA strands to kind right into a double helix spontaneously. Nevertheless, if the 2 strands are solely partially complementary, each strands can settle for a number of DNA molecules and be folded into a number of completely different shapes . Thus, DNA sequences are designed and folded onto themselves utilizing the origami methodology. Right here, the folded buildings are held collectively utilizing the aforementioned staple strands of DNA .
Purposes of DNA Origami
The result’s an enormous array of buildings of various complexities. Making a map of the USA utterly out of folded DNA is considered one of its extra amusing functions. However DNA origami has the immense potential to contribute considerably in a variety of fields, resembling prognosis and drug supply. Most cancers remedy is one such potential area the place it confirmed important efficacy and will contribute immensely .
*A nucleotide is likely one of the structural parts, or constructing blocks, of DNA and RNA. It consists of a base (considered one of 4 chemical compounds: adenine, thymine, guanine, and cytosine) plus a molecule of sugar, and considered one of phosphoric acid.
DNA Nanostructures: What’s So Particular?
Construction and composition are the 2 fundamental traits of a fabric that decide its chemical and bodily properties. Graphite and diamond, for instance, are each product of carbon – but, graphite is slippery and smooth whereas diamond is likely one of the hardest substances identified to humankind. Equally, the construction of DNA-based supplies on the molecular degree is what determines the properties they show.
An illustration of the significance of molecular construction may be seen within the DNA nanostructures that Dr. Samanta works with in her analysis lab. Typically, proteins and quick sequences of DNA don’t enter our cells in massive portions with ease; in actual fact, the presence of international DNA within the bloodstream is definitely an indication of an infection and is quickly combated utilizing bodily enzymes. Nevertheless, tiny snippets of DNA may be organized densely on the floor of a nanoparticle – Dr. Samanta encourages her college students to think about a Koosh ball for reference (Determine 2) – and the ensuing nanostructure is ready to enter cells with a excessive diploma of permeation, as much as two orders of magnitude greater than common DNA.
This function permits for using DNA nanostructures not solely in gene remedy but in addition within the remedy of illnesses and detection of genetic situations, which is what the Samanta Lab focuses on.
Determine 2: A Koosh Ball
Following Dr. Samanta’s analogy, the tiny centre of the ball represents the chosen nanoparticle. The snippets of DNA which might be hooked up to its floor are seen as spikes on the ball.
When you’d like to listen to extra in regards to the fascinating world of DNA and its immense potential, go to us on Spotify to take heed to our ChemTalk podcast with Dr. Devleena Samanta, affiliate professor of chemistry on the College of Texas, Austin, to be taught extra in regards to the favorite a part of her job, why she needed to be a scientist, and what she believes is an important downside we have to remedy.
Discover the ChemTalk podcast right here.
 “Deoxyribonucleic Acid Reality Sheet.” Nationwide Human Genome Analysis Institute. 24 August 2020.
 Rukkumani Rajagopalan, Jatinder V. Yakhmi, in Nanostructures for Most cancers Remedy, 2017
 “What’s DNA Origami?” BioSynthesis. 17 July 2017.
 Samanta, Devleena. Private Interview. Carried out by Roxanne Salkeld. 2 December 2022.