Exploring the role of ADP-Ribosylation in DNA repair

Review written by Jessi Hennacy (MOL, G5)

Preserving the integrity of DNA is crucial to maintaining a cell’s functions and life cycle. However, DNA is regularly under attack by chemical and physical agents, such as toxins and UV rays from the sun, that can cause breaks in the chemical backbone that holds a strand of DNA together. This DNA damage can lead to dire consequences if left unaddressed, with effects ranging from cell death to uncontrolled cellular proliferation, which leads to cancer. Thankfully, our cells have evolved mechanisms of repairing broken DNA in order to alleviate the risks of accumulating DNA damage.  

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Understanding the entirety of the Vibrio cholerae biofilm lifecycle: First insights into biofilm dispersal

Review written by Kimberly Sabsay (QCB, G2)

Individual cells go through life cycles, in which they grow and prepare for cell division. Similarly, in certain bacteria, groups of cells go through a synergistic cycle involving the formation and disassembly of biofilms. Biofilms are essentially groups of cells that surround themselves in layers of self-made extracellular matrix proteins and polysaccharides. A biofilm is a way for cells to protect themselves from dislocation or death by predation and are present in both beneficial and pathogenic bacterial microbiomes. The sticky extracellular matrix is a structure that pathogens such as Vibrio cholerae (the bacteria that causes Cholera) can hide in to avoid detection by immune cells and thus increase their virulence. In this way, biofilms essentially provide protective armor for bacterial cells that inhibits our ability to fight pathogenic infections. 

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dSPRINT: Machine learning for uncovering protein-ligand interaction sites

Review written by Sara Geraghty (QCB, G3)

Proteins are ubiquitous in our cells. Currently, it’s estimated that the human body contains between 80,000 and 400,000 protein molecules, all busily performing the many tasks that keep your cells running smoothly and ultimately go into making you. Not only do proteins form the structural framework of your cells, but they also protect your body against foreign pathogens, help digest your food, and send and transmit signals around your body. However, they don’t do this in isolation: proteins are constantly working hand-in-hand with other proteins and molecules in your body, like your DNA, RNA, small molecules, and ions. When your DNA is replicated, or an ion is actively transported, the proteins doing the job need to recognize those molecules (and often bind to them) in order to carry out their task properly. This fundamental process of a protein binding to a partner molecule, or ligand, is critically important in biological processes ranging from development to cancer. And yet, we know surprisingly little about what proteins bind what ligands, and where -- knowledge that is key in understanding, and possibly manipulating, the inner workings of cells.

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How the egg drives its own development

Review written by Olivia Duddy (MOL, G4)

How do animals produce a healthy egg cell? To answer this, many developmental biologists investigate the complex choreography of factors required for successful egg cell development, called oogenesis. This process is crucial to the survival and reproduction of many vertebrate and invertebrate species and, remarkably, diverse species often employ a common strategy where the growth of the egg cell is supported by an interconnected network of germline, or reproductive, cells. Like cellular factories, the job of the germline cells is to produce and export nutrients to the egg via connecting cytoplasmic canals. The nutrients these support cells supply to the egg include proteins and the nucleic acids that code for them, called RNA transcripts. 

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Newborn mice form memories of their mothers that last a lifetime

Review written by Amy Ciceu (2024) & Adelaide Minerva (PNI, G2)

As youngsters, we develop memories of and connections to our parents, who nurture us throughout not only our childhoods but also much of our lives. These memories and relationships play vital roles in teaching us how to navigate the world. Do other animals form similar memories? A recent study published by the Gould Lab in Princeton’s departments of Psychology and Neuroscience discovered that mouse pups form memories of their maternal caregivers within days of birth and that these memories endure as the pups age into adulthood. 

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Toward personalized medicine: how the gut microbiome shapes patient response to drugs

Review written by Truc Do (CBE, post-doc)

Our microbial residents and their impacts

It has been estimated that there are at least as many bacterial cells in our bodies as there are our own cells1. The vast and diverse collection of bacteria and other microorganisms that live within and on us is known as the human microbiome. We are colonized with microorganisms from birth, but the structure (composition) of our microbial communities evolves throughout our lives2. In recent years, it has become increasingly apparent that human health is inextricably tied to the state of our microbiomes. For example, Crohn’s disease is an inflammatory bowel disease of increasing prevalence. Changes in the composition of the gut microbiota, as a result of diet and other environmental factors, have been associated with severe Crohn’s disease states3.

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A new strategy for putting yeast to work

Review written by Sarah McFann (CBE, G5)

Many household goods, from dyes and plastics to contact lenses and aspirin, are made using petroleum byproducts. Over the past 150 years, chemical catalysts have been optimized to efficiently convert crude oil into starting materials for a wide range of products. Unfortunately, petroleum is a non-renewable resource, and emissions from petroleum processing are a big contributor to climate change. A team of bioengineers from the Avalos Lab at Princeton University is investigating an alternative: a petroleum-free way of manufacturing carbon-based goods that uses genetically engineered yeast to convert sugar into high-value products. 

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Structural insights into the liquid-like center of the eukaryotic CO2 concentrating organelle, the pyrenoid

Review written by Jessi Hennacy (MOL, G4)

All plants use the enzyme Rubisco to capture CO2 during photosynthesis, but Rubisco is hindered by a slow reaction rate and a counter-productive reaction that happens when the enzyme binds to oxygen instead of CO2. Algae, however, have a special organelle called pyrenoid that helps Rubisco capture CO2 more efficiently. Whereas most plants need to express high amounts of Rubisco to capture enough CO2 to grow, the pyrenoid supplies Rubisco with concentrated amounts of CO2 to improve the enzyme’s CO2 capturing activity. If a pyrenoid could be genetically engineered into crops, it could be possible for the plants to capture the same amount of CO2  with less Rubisco, thereby helping them grow with fewer resources. However, this advancement requires understanding the functional roles of proteins involved in building a pyrenoid. 

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New tricks to study the cell's trickiest proteins

Review by Abigail Stanton (MOL, G1)

The cell can be a chaotic place to work. Protein employees of all different types rush from room to room, delivering messages, building needed materials, and working together to keep the cell running smoothly. To learn how any one of these proteins does its job, researchers have to consider how they will structure their experiment to get the type of information that they need. One approach is observing the protein at work: what does it do on a normal day? How does it interact with its coworkers? Studying a protein in situ (in its original place) gives researchers the best sense of how the protein actually behaves. However, the complex environment of the cell can make it difficult to pick out the contributions of any one protein. To gain more detailed information, the researcher may need to sit the protein down for a one-on-one interview, purifying it away from the other components of the cell for in vitro (in a test tube) experiments. However, a protein’s behavior alone may be very different from how it acts surrounded by a crowd of molecules. To create the most useful experiment possible, researchers need to find ways to combine the context of in situ studies with the detail and experimental control of in vitro work. 

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Prince, perception and purple: The colorful world of wild hummingbirds

Review written by Jarome Ali (EEB, G4)

Who is the funkiest musician of all time, and why is it Prince? And what does this have to do with hummingbirds? 

Central to Prince’s aesthetic was his tasteful use of purple, so much so that Pantone Color Institute released a shade of purple in his honor. Prince was on to something. Purple is not just the color of royalty, but it is also unique among the colors we can see--it is nonspectral.

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