BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: #APBiology

Exploring Multicellularity on Planet Earth

Billions of years ago, it is believed that some event—whether it be a meteor crash-landing on planet Earth, or a lightning strike creating amino acids and proteins—sparked the origin of life. From there, single celled organisms, like bacteria, made their home on our planet; and eventually, unicellularity became multicellularity. The reason behind this phenomenon, though, is what continues to be unknown. What really is the point of the majority of organisms being compiled of millions of cells, and not just one? 

Scientists at Lund University strive to answer this question. In order to do this, green algae from Swedish lakes were taken into their lab, as this specific botanic organism is extremely suitable for the goals of this experiment. For one, it is a eukaryote, which will allow researchers to gain insight on the evolution of all eukaryotes, in general. They are widely studied in the study of evolution because of their very apparent evolutionary process. There is a great amount of data to reveal that all eukaryotes have common ancestry, including the presence of double membranes, circular genomes, ribosomes, linear chromosomes, and more in all eukaryotic organisms. 

Another reason as to why green algae is such an appropriate fit for an experiment exploring the evolutionary characteristics of unicellular and multicellular organisms is that it is sometimes unicellular, other times starts off this way but then becomes multicellular, and the remaining types are always multicellular. This makes green algae the perfect candidate for an experiment such as this. Data from the environments of all these different cellularly-dense types of algae was collected and compared to one another. While doing this, scientists looked out for the adaptations promoted by the environments the algae were in, what conditions exactly promoted unicellularity or multicellularity, and why the form of life it encouraged was beneficial to the organism. 

Previously, it had been theorized by evolutionary biologists that multicellularity benefited organisms that utilized it, but the Lund University research team was shocked at the results they found from analyzing the environmental data of the algae: there were no benefits of living multicellularly for these organisms. A member of the study, Charlie Cornwallis, made the following comment on the experiment’s outcomes: “I was surprised that there were no benefits or costs to living in multicellular groups. The conditions that individual cells experience can be extremely different when swimming around on their own, to being stuck to other cells and having to coordinate activities. Imagine you were physically tied to your family members, I think it would have quite an effect on you.” 

At the conclusion of the study, Charlie Cornwallis made one final statement: “The results of this study contribute to our understanding of how complex life on Earth has evolved….The next time you walk along the shores of a lake rich in nitrogen just imagine that this fosters the evolution of multicellular life.”

Green algae under a microscope

Green algae under a microscope.

The Blood Brain Barrier Can’t Block This!

University of Wisconsin-Madison Professor, Shaoqin “Sarah” Gong is ready to take on finding cures for brain disease such as Alzheimer’s and Parkinson’s disease. Gong and her colleagues strive to enable a “noninvasive, safe and efficient delivery of CRISPR genome editors” that can be used as forms of therapy for these diseases. According to MedlinePlus, there are many forms of brain disease, some caused by tumor, injury, genetics; however, Gong’s research focuses on degenerative nerve diseases. Degenerative nerve diseases can affect balance, movement, talking, breathing and heart function. The reason cures for degenerative nerve disease are difficult to create is because of the blood brain barrier. According to the American Society for MicroBiology, the blood brain barrier is a feature of the brain and central nervous system blocking the entrance of “microorganisms, such as bacteria, fungi, viruses or parasites, that may be circulating in the bloodstream”. Unfortunately, the barrier block is a very selective site that won’t let vaccines and therapies through. Fortunately, Gong’s nano-capsules with CRISPR’s genome editors point toward brain disease therapy and a cure.

 

Alzheimer's disease brain comparison

Gong’s study proposes dissolvable nano sized capsules that can carry CRISPR genome editing tools into organs. According to CRISPR Therapeutics, CRISPR technology meaning Clustered Regularly Interspaced Short Palindromic Repeats is an “efficient and versatile gene-editing technology we can harness to modify, delete or correct precise regions of our DNA”. CRISPR edits genes by “precisely cutting DNA and then letting natural DNA repair processes take over.” CRISPR targets mutated segments of DNA that can produce abnormal protein causing diseases such as degenerative nerve disease.  CRISPR works with the help of a guide RNA and Cas9. Together the complex can recognize and bind to a site next to a specific target sequence of DNA that would lead to the production of an abnormal protein. CAS9 can cut the DNA and remove a segment. As a result natural DNA pathways occur and RNA polymerase will return to rebuild and correct the mutated segment. 

via GIPHY

Consequently with the addition of glucose and amino acids the nano-capsules containing CRISPR Technology can pass through the blood brain barrier to conduct gene editing to target the gene for the amyloid precursor protein that is associated with Alzheimer’s. The topic of gene editing coincides with the Gene Expression portion of the AP Biology curriculum. In the topic of gene expressions 2 processes are emphasized: transcription (the process of making an RNA copy of DNA) and translation ( the process of making proteins using genetic information from RNA). In the CRISPR technology the editing of genes closely relates to the process of transcription. Transcription mistakes can be made which can lead to mutations, these mutations can potentially cause nonsense, missense or deletions of nucleotides ultimately producing wrong codons that would code for incorrect/abnormal proteins. However, the CRISPR technology would be able to correct these mutations in the DNA, replacing the incorrect nucleotides to correct ones and preventing the production of abnormal proteins. Fortunately, Gong’s unique nano-capsules have successfully been tested on mice, giving scientists hope that treatments and therapy for these brain diseases are coming soon and can help many.

The End Of Malaria

Introduction

Attention everyone, what if we told you that there is a way to potentially wipe out the bad mosquito species that causes malaria? Scientists have developed a genetic weapon, a self replicating bit of DNA called a gene drive, that interferes with the mosquitoes ability to reproduce. This can be revolutionary and save millions of children’s lives in the future.

What is malaria

Malaria is a deadly disease killing about 643,000 people every year. It is transmitted by a parasite -mosquito bites. The symptoms of malaria include fever, chills, and other flu-like symptoms.

Malaria knocks you flat, keep covered, use your repellent (4647891178)

How it works 

Gene drives work starts with taking one transgenic organism into the lab so it can be modified. It then can be engineered for release into wild populations to spread an altered allele. Two types of drives are possible: modification drives spread an advantageous gene, while suppression drives spread a gene that reduces the population. As the gene spreads this ultimately allows for the death of mosquitoes to spread exponentially. This topic also relates to what we learned in the AP Biology units on genetics and DNA. The connection to genetics is evident in the ability to control breeding of species, such as mosquitoes, using the knowledge of Punnett squares and the principles of dominant and recessive traits. However, the most significant connection between genetics and mosquito control lies in the ability to manipulate and alter DNA.

CRISPR illustration gif animation 1

Future

Gene drives can potentially save millions of lives by reducing mosquito populations and preventing the spread of malaria. The technology is being tested in Africa, where malaria is most prevalent. Soon it will hopefully be around the entire world and save millions of lives all together. 

 

 

Biomaterial Breakthrough: A New Hope for Heart Attack Patients

In the world of science and medicine, new breakthroughs are always being made. In very recent news, a team of researchers from the University of California San Diego has created a game-changing biomaterial that could be the answer to treating tissue damage caused by heart attacks. This new discovery is not only exciting for those suffering from heart conditions, but it also showcases the importance of understanding cell and tissue repair in AP Biology.

Here’s how it works: the biomaterial, which can be injected intravenously or infused into a coronary artery in the heart, is made from a hydrogel derived from the extracellular matrix (ECM) of cardiac muscle tissue. The hydrogel forms a scaffold in damaged areas of the heart, promoting cell growth and repair. In previous studies, the team had already proven the effectiveness of the hydrogel when injected directly into the heart muscle. However, this method could only be used a week or more after a heart attack, as injecting sooner could cause damage during the procedure.

But this new biomaterial takes things to the next level. It’s put through a centrifuge to sift out larger particles, leaving only nano-sized particles, and then undergoes dialysis and sterile filtering before being freeze-dried. Adding sterile water to the final powder results in a material that can be infused into a blood vessel in the heart or injected intravenously, allowing for immediate treatment after a heart attack.Depiction of a person suffering from a heart attack (Myocardial Infarction)

And that’s not all! The biomaterial was tested on rodent and porcine models of heart attacks, and researchers found that not only did it pass through blood vessels and into the tissue, but it also bound to cells and closed gaps in the blood vessels, reducing inflammation and accelerating healing. In addition, the team tested the hypothesis that the same biomaterial could help target inflammation in rat models of traumatic brain injury and pulmonary arterial hypertension.

So, why is this important from an AP Biology perspective? Well, in the course, we’ve learned about the body’s ability to repair and regenerate cells and tissues. By mimicking the B blood cells’ ability to reduce inflammation and react to an infection, this new biomaterial is a prime example of how that knowledge can be applied in the real world to help improve human health. It’s a new approach to regenerative engineering, and the possibilities of treating other difficult-to-access organs and tissues are endless.

Regenerative-Medicine-Stem-Cells-Tissue-Engineering-Biomaterials

The researchers, along with Ventrix Bio, Inc., a startup co-founded by lead researcher Karen Christman, are hoping to receive FDA authorization to conduct a study in humans within the next one to two years. This is exciting news for those affected by heart conditions, and we can’t wait to see what the future holds for this groundbreaking biomaterial.

Read it and wheat…

Wheat, corn, and rice are the most important crops around the world. As someone who enjoys baking, wheat is the base of almost all the desserts and bread recipes I bake. However, as I have become more interested in baking various types of bread, I wondered how gluten is formed and how bread textures change based on how long I kneaded the dough. According to Jessica R Biesiekierski in her article “What is Gluten”, Gluten is “complex mixture of hundreds of related but distinct proteins, mainly gliadin and glutenin.” The gluten matrix is essential to the quality of bread dough. It has the ability to act as a “binding” agent and is also used in marinades and even capsules in medication.  The biology of gluten and its structure depend on the ration of glutenin and gliadins. Each component has different functions that can effect “viscoelasticity”. In her article Biesiekiersk, worked to find evidence that “exposure to gluten may be increasing with changes in cereal technology”. There are many diets and intolerances caused by gluten such as the gluten free diet, gluten disorders, coeliac disease wheat allergy and sensitivity. In conclusion of their study, they determined “Gluten is a complex protein network and plays a key role in determining the rheological dough properties and baking qualities.” However, they came across a challenged. They learned that protein structure can “vary dependent on several factors”. Ultimately, make “analysis and definitions difficult”. And overall they conclude that “further work is needed to completely understand non-coeliac gluten sensitive”.

Another study that researched viscoelasticity is by is Peter R. Shewry, Nigel G. Halford, Peter S. Belton, and Arthur S. Tatham studied “The structure properties of gluten: an elastic protein from wheat grain”. According to Science Direct, viscoelasticity refers to a material’s tendency to act like a fluid or a solid. An additional article that explores viscoelasticity.

Vehnäpelto 6

They manipulate the “amount and composition” of HMM subunits concerning the strength or change of gluten structure and properties. These scholars describe wheat as a plant with many properties, however, they emphasized “viscoelasticity”. In terms of this research, viscoelasticity is “the balance between the extensibility and elasticity determining the end use quality.” The scholars use the dough as an example stating that “ highly elastic (‘strong’) doughs are required for bread making but, more extensible doughs are required for making cakes and biscuits”. In the study, these scholars focused on the HMM protein subunits of gluten. At least 50 different types of gluten proteins can be produced during the kneading process; however, these researchers have chosen to focus on the HMM subunits of glutenin. HMM, subunits, X type, and Y type can be only found on one chromosome in wheat cells. These two subunits are 70 % accountable for the viscoelastic variations in bread. This presentation allowed the researcher to see how stable and unstable the subunits were which would play a role in their ability to interact with peptides. In addition, these peptides may relate to the role of gluten in stabilizing the structures and interactions of the subunits.

US Navy 050102-N-5837R-011 Culinary Specialist 3rd Class Joshua Savoy and Culinary Specialist 3rd Class Davy Nugent prepares bread in the bakery aboard the Nimitz-class aircraft carrier USS Abraham Lincoln (CVN 72) Both articles emphasized the importance of protein structure. AP Biology greatly emphasizes the importance of Organic compounds. Proteins have a few structures that are ultimately composed of sequences of amino acids to create polypeptide chains. From primary structure proteins can become more complex by forming alpha helixes and beta pleated sheets. From that point 3D structures can be made. Gluten has a very structure characterized by “high allelic polymorphism encoding its specific proteins, glutenin, and gliadin”. This leads to wheat producing “unique types and quantities of these compounds”, these types and quantities can vary based off “growing conditions and technological processes”.

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