DNA Constituents and DNA Ambulance: Scientific Implications of Discovery

DNA Constituents and DNA Ambulance: Scientific Implications of Discovery

Question: DNA ambulance is the first discovery of its kind. Discuss what DNA constitutes and provide an overview of the scientific implications of this discovery.

DNA

- DNA or deoxyribonucleic acid is located within the cell nuclei and it makes up the body.

- DNA is the basic building block of the human body

- The basic structure of the human body is the cell, billions to trillions of which form part of the structure.

- Each cell comprises hereditary material and can make copies through reproduction and multiplication

- Following a specific duration of time, the old cells die off

- Parts of the cells are known as organelles

- The nucleus is the central part of the cell which carries the blue print for its functioning and informs the cell when to grow, reproduce and die. It also contains the DNA.

- The mitochondria refers to the powerhouse of the cell; energy for various activities of the cell is produced by it

- Cytoplasm is the jelly like fluid located within the cell within which other organelles float

- Endoplasmic Reticulum assists in the processing of molecules such as proteins created by the cell

- Ribosomes are over the endoplasmic reticulum and process genetic instructions or blueprints within the DNA and come up with new proteins

- Lysosomes and peroxisomes aid in digestion of foreign bacteria invading the cell and ridding it of toxic substances

- Cell membrane is the outer lining of the cell

Chromosomes and DNA

- Inside the nucleus, DNA strands are tightly packed to constitute chromosomes

- Chromosomes are visible during the cell division and each chromosome contains a point of constriction called the centromere from which two arms are formed

- Short arm of the chromosome is called the p arm while the long arm is called the q arm.

- Humans have 23 pairs of chromosomes totalling to 46. 22 of the pairs called autosomes are the same in men and women

Genes and DNA

- Genes are hereditary material placed within the cell nucleus and genes made of DNA act as instructions to create molecules known as proteins

- Human Genome Project has calculated that humans have between 20 to 25,000 genes and each person has 2 copies of each gene, one inherited from every parent

- Small percentage of genes (around 1 percent of the total) differ between people and form the grounds for paternity tests and DNA analyses

- DNA is the hereditary material lies within the nucleus and most of this is called nuclear DNA. Some small portion of the DNA can be found in the mitochondria and refers to as mitochondrial DNA or tDNA

- DNA is composed of the adenine, guanine, cytosine and thymine

- DNA bases pair up with each other to form units known as base pairs

- Each base is attached to sugar and phosphate molecule

- Human DNA contains around 3 billion bases and are common in two persons for 99% of the total bases

- Bases are sequenced differently for differing information

- A nucleotide is a combination of a base of sugar and phosphate. These are arranged in dual strands forming a spiral known as the double helix. DNA can make copies of itself as both strands of the DNA open up and create a copy of each to become two DNA strands. Each new DNA has a copy of the previous DNA from which it was replicated

- Mitochondria contains small amount of DNA and each cell contains 1000s of mitochondria lying within the cytoplasm

- mtDNA contain 37 genes enabling it to function in a normal fashion. 13 of these genes provide instructions for creating enzymes involved in energy production by oxidative phosphorylation

- Rest of the genes called tRNAs or transfer RNAs and ribosomal RNAs (rRNAs) which play a crucial role in the synthesis of protein

DNA Ambulance and Scientific Implications

- University of Toronto scientists have discovered how severely damaged DNA is transported inside the cell and the manner in which it is repaired

- This discovery could unlock how cancer operates and though scientists were aware that severely injured DNA was taken to specialised hospitals in the cell to be repaired, there was still no understanding of how it got there.

- The DNA ambulance and the road it takes has now been discovered

- Dr. Mekhail and his team from the University of Toronto have discovered this DNA ambulance which is a motor protein complex through the use of yeast cells

- The researchers also found that the DNA hospital called the nuclear pore complex repairs damaged DNA in an inaccurate way

- The inaccuracy in the fix is essential as DNA contains instructions for all genetic information

- Though the repaired DNA can still replicate, it carries irregular cell instructions(which could lead to cancer)

- Process allows cells to survive injury at a massive cost

- Cell carries a compromised genome which is stable and can be replicated leading to greater issues

- Advanced microscopy was used to track the damaged DNA in the living cells

- Tracking shows that this DNA ambulance is essential for damaged DNA to effectively change location within the nucleus

- Cancer occurs when chromosomes break and are misrepaired

- Location of the break within the nucleus of the cell has been found to have a huge impact on repair efficiency

- Research implications can extend to a vast number of developmental as well as disease settings

Facts and Stats

- The study has been published in Nature Communications