yurogenital – BioQuakes

Scientists have now created a new method of using CRISPR genome editing, which would allow them to activate genetics without breaking the DNA. It could potentially be a major improvement in using gene editing techniques to treat human diseases. Currently, most of the CRISPR systems work by creating DSBs or Double strand Breaks in regions of the genome targeted for editing. Many scientists and researchers have opposed creating breaks in the DNA of living humans. So the Salk group tried their new method to treat diseases such as diabetes, kidney disease, and muscular dystrophy in the mouse models.

CRISPR has proved to be a powerful tool for gene therapy, but there are still many concerns regarding some mutations generated by the DSBs though the Salk group is able to get around that concern. Originally, Cas9 enzyme couples with guide RNA to create DSBs. But just recently, researchers have used a dead form of dcas9 to stop the cutting of DNA. DCas9 would couple with transcriptional activation domains, that turn on targeted genes. But it is still difficult to be used in clinical applications.

Salk group team combined dcas9 with bunch of activator switches to uncover a combination that would work even when the proteins are not fused with one another. These components all work together to influence endogenous genes. It would influence genetic activities without having to change the DNA sequence.

In order to prove the usefulness of this method, scientists used mouse models of acute kidney disease, type 1 diabetes, and a form of muscular dystrophy. They engineered their new CRISPR system to boost the expression of an endogenous gene that would reverse the symptoms of the disease. In all three cases, they reversed disease symptoms.

To understand more, click here.

Photo credit: Martyn Fletcher

Clock Change is Actually Great For Your Brain!

By yurogenital

On December 10, 2017

In Student Post

November this year, our clocks went back an hour, which accelerated the arrival or darker evenings and seemingly “shorter days”. It doesn’t actually make the days any shorter, in merely just shifted an hour of available daylight from the evening to the morning. Most people take lighter evenings as a priority over lighter mornings, arguments are always made over the benefits for easier travel in lighter evenings from clock changes. However, research suggests that holding onto lighter mornings could give more advantages. Having light in the morning, instead of any other time of the day, leads significant brain-boosting results. In fact, it helps us to function much better.

Credit: Attribution license: Porsche Brosseau

Source

All living animals and plants on Earth revolve their lives around the 24-hour cycle of light and dark. For humans, we desire to sleep during the dark night, and our bodies are honed to environmental light via a biological chain reaction.

We, humans, detect light intensity by special cells in the retina, then the information is relayed to the internal body clock in the brain, called the suprachiasmatic nucleus. It is in the hypothalamus (which uses the endocrine system to regulate internal body processes), which is linked to hormone secretion, through the pituitary gland. These light messages’ job is to internalize information about light intensity in the surrounding environment.

The chain reaction continues with the brain driving the secretion of the hormone cortisol for a specific time of the day, it is in low levels in the dark and high levels in the light. Cortisol is a very important hormone that has very dramatic effects on the human brain and body. The cortisol is also known as the “Stress hormone” that keeps us healthy through its 24-hour pattern.

The cortisol awakening response(CAR) occurs the first 30 minutes of waking up, it is a strong burst in cortisol secretion. The lighter the mornings, the bigger the CAR. Which directly results in a better functioning brain throughout the day. In an experiment, people who have greater seasonal depression, stress, anxiety and lower arousal exhibited the lowest winter CARs. But when they are exposed to artificial light during their awakenings, their CAR was restored. Thus proving that morning light is the most effective treatment for the winter blues.

Other research has also shown that CAR in the morning is directly linked to better brain plasticity, better goal-setting, decision-making and executive function.

The burst of cortisol secretion in the morning sweeps throughout the entire body where it is recognized by receptors on all body cells. The receptors then generate the biological chain reaction to allow us to function better for the day ahead. A lack of light in the morning can make us feel not functioning fully, and an exposure to light in the morning is extremely beneficial.

Source:

https://www.scientificamerican.com/article/why-the-clocks-changing-are-great-for-your-brain/

Fish might be shrinking!

By yurogenital

On October 11, 2017

In Student Post

To all the seafood lovers, you are being warned here first! The tiny piece of tuna on your plate will soon become even smaller due to climate change. Fish in the ocean will struggle to breathe due to the increasing water temperature, and many species of fish will likely shrink. According to a study published in Global Change Biology, the author predicts a decrease in sizes of the fish by as much as 30 percent. As Nexus Media explains, fish are cold-blooded animals, which means that they cannot regulate their own body temperature. Daniel Pauly, the study’s lead author and a University of British Columbia research initiative, say that due to the increase in ocean temperature, fish will have a higher metabolic rate and have to consume more oxygen. The whole metabolisms in the fish’s body, all the chemical reactions, are accelerated.

Credit: Attribution license: Taras Kalapun,

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So if the fish need to have more oxygen intake, why not just grow bigger gills? In Pauly’s research, he suggests that growing bigger gills won’t help. According to the article, the gills being mostly two-dimensional, just cannot keep up with the three-dimensional growth in the rest of the fish’s body. When a fish grows 100 percent larger, its gill could only grow about 80 percent or less, according to the study. When a gill can no longer supply enough oxygen for a fish’s larger body, the fish will just stop growing larger all together, according to William Cheung, a director of science for the Nippon Foundation. In order to match the decreased supply of oxygen, fish will have to lower their demand, which means that fish of all kinds will shrink as a result of climate change.

There is already evidence to the phenomena of fish shrinking due to climate change, researchers in the North Sea have found that fish stocks like haddock and sole had decreased in body size over the past couple decades, and it is primarily due to climate change since commercial fishing and other factors have been corrected. Furthermore, the entire ecosystem will be affected since the larger fish eat the smaller ones, and a change in body size would alter food web interactions and structure.

To read more about other impacts of climate change on marine species.

Sources:
https://www.scientificamerican.com/podcast/episode/climate-change-might-shrink-fish/

BioQuakes

AP Biology class blog for discussing current research in Biology

Author: yurogenital

CRISPR used to treat diabetes, kidney disease, muscular dystrophy

Clock Change is Actually Great For Your Brain!

Fish might be shrinking!

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