Science News of 2015

Tamara Ilic
Patric Youell
Science 9B
January 21st, 2016
                                                           Science News 2015

Year of 2015 was very successful when it comes to scientific discoveries. Mankind made various discoveries on different fields of science; biological age and how people grow old at different rates, newly discovered bacteria that might have triggered beginning of life and the most amazing discovery that is very significant for the future of mankind is the discovery of water, therefore conditions for life on Planet Mars.

Not all bodies act their age

Ageing has always been one of the most mysterious topics of science and life that provoked curiosity in people. Study out of Duke University analysed health of approximately one thousand 38 year-olds (figure 1) this examination led them to a conclusion that people grow old at extreamly different rates, some resemble up to decade older while others resemble few years younger. This so called "biological age" is persistent to be based on three health indicators: body mass index, blood pressure and cholesterol level. The question that captured scientists and the publics attention is "Why some people can live to 120 with no disease, and others are already in bad shape at age 70"  says Martin Hetzer, molecular biologist at the Salk institute for Biological studies in La Jolla, California. If the accurate answer to this question would be given, scientists may reveal the secret of ageing, therefore create anti-ageing serum. 

Figure1
Scientists examined heath of almost one thousand 38-yearolds based on three health indicators: body mass index, blood pressure and cholesterol level and found out that some resemble a decade older while other resemble few years younger.

Ageing can be triggered by many different cellular damages. Source states that recent scientific studies came to a conclusion that molecular damage within cells might be the essence of ageing. Researchers have been comparing and examining teeth of young and old people in order to discover roots of ageing, instead they identified that young and healthy people have long stretches of DNA compacted in neat bundles known as heterochromatin, while bundles of old people are not as stable and compacted. By examining the teeth of young and old people researchers detected that some people are ageing much faster than others, the most common reason of premature ageing is known to be Werner syndrome. Werner syndrome, known as the "adult progeria" is caused by deficiency of Werner protein. Werner syndrome causes mutation and disorganisation of ones heterochromatin (figure 2) which leads to cellular ageing, cataracts, osteoporosis and other signs of ageing.
Individuals which obtained werner syndrome own "birdlike" face expression, thin arms and legs,thick trunks and usually struggle from the lack of hair.  It is hard to tell if an individual struggles from werner syndrome at the young age since the actual symptoms begin developing during puberty. Werner syndrome can be inherited from parent, at least one parent needs to carrie one copy of the mutated werner gene, therefore child will develop both copies of werner gene further causing cellular mutations.

Figure2In normal cells (left) DNA is compacted in neat bundles. Cells affected with Werner syndrome(right) have disorganised heterochomatin and their DNA is not compacted in neat bundles. You can notice how premature ageing causes the enlargement of a nuclei. 

Another very common trigger of ageing is the breakdown of important brain barriers. Ageing may also begin when essential barriers of brain stem cells break down. When young stem cells divide, they build a wall that separates the cellular junk called ubiquitin from one daughter cell and enters another, the one without ubiquitin is able to grow and divide properly. As people grow old barrier that keeps the cellular junk from spreading breaks down (figure 3). Ubiquitin enters both daughter cells and reduces their ability to produce new healthy cells. The blood-brain barrier is another protective barrier that weakens over time. This barrier protects protects the brain from dangerous poisons in blood. However, this barrier leaks out with age and becomes unable to protect the brain from toxins in blood. Individuals with weak barrier have  problem with learning and memorising. Destruction of blood-brain barrier and brain stem cell barrier is actually natural ageing, meaning every individual has to experience this breakdown at the certain age.
Ageing triggers emotional and regenerative deterioration in the brain of an adult. It increases sensibility and neurodegenerative disorder. In my opinion most common trigger of ageing is activated by mental health, meaning when an individual starts overthinking the age one becomes so occupied by the idea of ageing that he/she ages much faster instantly. Experiments in which the heterochronic parabiosis method is used show that circulating vitality factors in blood change adding phenotypes in brain. Heterochronic Parabiosis is a method in which the circulatory systems of two animals, young and old, are physically joined together. This experimental model is used in ageing research.

Figure3
Young brain stem cell (left) ubiquitin enters only one daughter cell, while in old  stem cell (right) ubiquitin enters both cells and reduces their ability to produce healthy cells.

The most effective way to explore secrets of ageing is through method known as the heterochronic parabiosis. Experiments in which the heterochronic parabiosis method is used show that circulating vitality factors in blood change adding phenotypes in brain. Heterochronic Parabiosis is a method in which the circulatory systems of two animals, young and old, are physically joined together. This experimental model is used in ageing research, so far it helped scientists understand the most common differences between the young and old organisms.

I consider this ageing researc very significant for humankind, since ageing is the biggest mystery of life. Every individual dreams of making the time stop, becoming immortal or at least slow down the ageing process. I'm very inspired by this discoveries, it provokes curiosity inside of me and makes me wonder how may I contribute to this research. Now that i read and understood this topic I might decide to study human ageing in the future and therefore form an anti-ageing serum.

Microbe discoveries spur rethink of treetop of life

Biologists have set up a theory that somewhere between 2-1 billion years ago simple-celled organisms, prokaryotes, performed process of endosymbiosis to absorb once free-living bacteria which developed into sausage-like organelle known as mitochondrion. Product of endosymbiosis was a complex cell called eukaryote which triggered the complexity of life. In 2015, scientists have discovered microbes ,in Arctic see-mud, which they believe are the closest relatives found to eukaryotes. Researchers have been analysing the mud and found previously unknown, unusual singled-celled microbe which they named Lokiarcheota.  What's so interesting about this microbe is that it carries similar DNA to a single-celled organism called archaea, sister group to bacteria, yet Lokiarcheota has a similar dynamic structure to eukaryotes, which would help them swallow another bacteria. Biologists have recommended to represent the combination of bacteria and archaea as a ring of life rather than the tree (figure 4), since ring provides a clear image of bacteria and archaea merging to form eukaryotes, while tree does't show any merging.

Figure4
Tree top of life (upper sketch) doesn't show a clear model of archaea and bacteria merging to  form a eukaryote, while ring of life (lower sketch) shows very understandable image of merging and the outcome.

"We don't have all the existing pieces right now because a lot of the diversity of microbial eukaryotes remains unexposed." (Patrick Keeling, studies early eukaryote history at the University of British Columbia in Vancouver) Up to late 1980's scientists thought that eukaryotes spreads out to three tree branches of mostly multicellular organisms (Kingdoms of: animals, plants and fungi) although new studies have downgraded the multicellular kingdoms to secondary smaller branches of mostly single celled protists which stretched to 5-7 branches.

This discovery is very significant to the origin of mankind and every other organism. Ring of life might provide further evidence for the common ancestor of all organisms, which triggered the complexity of life. By finding the common ancestor, scientists will be able to do further research on how it led to formation of every living organism that ever existed on planet Earth.

Best evidence for water on Mars

Not only that 2015 has made some significant discoveries on planet Earth, but humankind has took one big step towards the disclosure of life on another planet. Not so long ago scientists have discovered a frozen liquid on planet Mars.  In 2015 they have unravelled a liquid form of salty mineral water. The founding of the brine, the salty mineral solution, (look at figure 5) is the most significant evidence founded yet. The liquid was spotted oozing against the hillside marks, by the Reconnaissance Orbiter Spacecraft.  With this discovery scientists have gotten a more clear picture of physical aspects of the "Red Planet". The finding of the liquid indicated that there is possible life on Mars. This finding is very outstanding for the future of humanity, since this might lead to birth of new primitive life and another planet which humans might settle.

Figure 5
This image shows the oozing salty mineral liquid against the hillside marks of the Red planet.

Since 2012 the Curiosity Rover (figure 6) has been roaming Mars and had spotted interesting scientific discoveries. Nitrogen, which is used to make biological molecules such as, DNA and proteins has been found laying on the surface of Mars. 

Figure 6
NASA's car-sized robotic rover that has dicovered nitrogen used in forming DNA and proteins.

The study of six Martian meteorites, which were blasted into space because of asteroid impacts, had exposed that one of their substances is methane, which is the food source of microbes on Earth. If microbes are present on Mars they could use the methane from the martian rocks to extract energy which could lead to the forming of life on Mars. To discover if there is actually life on Mars is yet to be known until 2020 when NASA  plans to launch a rover on the planet. The rover would collect rock samples which would be sent back to Earth for further analyses.

This amazing discovery of liquid form of water, methane, nitrogen leads to two possibilities, both equally significant to mankind. One possibility is that there is already existing life on Mars, second possibility includes humans settling on the new planet, therefore spreading human species. One thing is for sure, there is enough material needed for assembling life on Mars.

2015 was definitely important year when many discoveries of different science fields were recorded. These explorations are just a puzzle piece that make up a whole puzzle. Scientists are now one step closer to; finding what causes human ageing and forming the anti-ageing serum, discovering surprising ancestors and affirming weather there is already existing life on planet Mars or if the conditions for human life are present.

Bibliography:

"Year in Review: Not All Bodies Act Their Age." Science News. N.p., n.d. Web. 07 Mar. 2016.

"Quantification of Biological Aging in Young Adults." Quantification of Biological Aging in Young Adults. N.p., n.d. Web. 07 Mar. 2016.

"Heterochronic Parabiosis Model in Aging and Stem Cell Research." Stem Cell Assays RSS. N.p., n.d. Web. 07 Mar. 2016.

"Werner Syndrome." Genetics Home Reference. N.p., n.d. Web. 07 Mar. 2016.

"Year in Review: Microbe Discoveries Spur Rethink of Treetop of Life." Science News. N.p., n.d. Web. 07 Mar. 2016.

Taylor, John W., Elizabeth Turner, Jeffrey P. Townsend, Jeremy R. Dettman, and David Jacobson. "Eukaryotic Microbes, Species Recognition and the Geographic Limits of Species: Examples from the Kingdom Fungi." Philosophical Transactions of the Royal Society B: Biological Sciences. The Royal Society, n.d. Web. 07 Mar. 2016.

"Year in Review: Best Evidence Yet for Water on Mars." Science News. N.p., n.d. Web. 07 Mar. 2016.

NASA. NASA, n.d. Web. 07 Mar. 2016.