In their final talk, Walther and Farese explain how proteins are targeted specifically to the surface of lipid droplets. This has functional consequences since proteins at the surface of lipid droplets govern lipid droplet growth and hydrolysis, and some of these proteins are associated with diseases. Farese and Walther end their talk by describing a… Continue Reading
iBiology Podcasts
Robert Farese Jr. & Tobias Walther Part 2: Mechanisms of Lipid Droplet Formation
In Part 2, Walther and Farese explain in more depth how lipid droplets form in cells in an organized manner. Triglycerides and other neutral lipids are made in the ER membrane. They accumulate in localized regions of the membrane that grow towards the cytosol and eventually bud off into lipid droplets. Farese and Walther describe… Continue Reading
Robert Farese Jr. & Tobias Walther Part 1: An Introduction to Lipid Droplets
All life requires metabolic energy but energy supplies and demands change over time. For this reason, organisms have developed ways to store energy, predominantly as fat. Neutral lipids are packaged into lipid droplets, small organelles found in most eukaryotic cells and in some prokaryotes. Lipid droplets play a critical role in an organism’s physiology; too… Continue Reading
James Haber Part 3: Mutations Arising during Repair of a Broken Chromosome
DNA synthesis that occurs during repair is much less accurate than normal DNA replication. Using the yeast mating type switching system, Haber’s lab identified base pair substitutions, frame shifts and other mutations that occur when the newly synthesized strand dissociates from the template strand during homologous recombination. Interestingly, Haber found that sometimes the newly synthesized… Continue Reading
Kevin Esvelt Part 2: Gene Drive and Local Drive
Esvelt’s second talk focuses on strategies to allow for the safe implementation of localized gene drive technologies that do not spread indefinitely. Daisy drive systems are made up of multiple elements connected like a daisy chain such that each causes the next to be preferentially inherited. They are designed to be self-exhausting by losing elements… Continue Reading
Kevin Esvelt Part 1: Gene Drive
Evolution has selected wild organisms to be extremely well adapted to their environment. Because most genetic changes introduced by humans divert the resources of the organism to benefit humans, such mutations are typically eliminated by natural selection in the ancestral habitat. In his first talk, Dr. Kevin Esvelt explains how self-propagating CRISPR-based gene drives can… Continue Reading
Víctor de Lorenzo: Bioremediation: Cyborg-ization of Soil Bacteria for Smart Degradation of Environmental Pollutants
Dr. Victor de Lorenzo discusses applications of bacteria as whole-cell catalysts for decontamination and bioremediation. Dr. de Lorenzo shows that many bacteria can use pollutants as carbon sources, allowing them to decontaminate dangerous chemicals in the environment. He highlights one example of engineering the bacterium Pseudomonas putida for bioremediation, using a set of standardized tools, to metabolize… Continue Reading
Tracey Goldstein & Koen Van Rompay: Studying Coronaviruses: Vectors to Vaccines
When an infectious disease outbreak happens, medical workers and public health officials mobilize, but there are also teams of researchers that snap into action. Dr. Tracey Goldstein and Dr. Koen Van Rompay are both actively involved in different initiatives to find answers surrounding the COVID-19 epidemic. They talk about the process of studying coronaviruses and… Continue Reading
Hans Clevers Part 3: Organoid Technology for Disease Modeling
In his third talk, Clevers describes how organoids can guide our understanding of disease progression in cancer. In addition, using Cystic Fibrosis and cancer as examples, Clevers shows how organoids can be used to predict therapeutic outcome in patients. Continue Reading
Hans Clevers Part 2: Generating Epithelial Organoids from Adult Tissue
In his second talk, Clevers shows how one can apply what we have learned from developing gut organoids to generate mini-organs for other epithelial tissues, like liver and lung. Clevers shows that these organoids have a similar expression profile as well as structural characteristics to those observed in real tissue. In addition, he shows how… Continue Reading
Hans Clevers Part 1: Discovery and Characterization of Adult Stem Cells in the Gut
In his first talk, Dr. Hans Clevers provides a historical perspective on the discovery of adult stem cells in the gut. They identified a Wnt-dependent, rapid proliferating population of cells at the bottom of the crypt which seemed to be important for generating all epithelial cells in crypts and villi, and they hypothesized that these… Continue Reading
Emery Brown Part 2: The Dynamics of the Brain Under Anesthesia
All general anesthetics act in the brain stem region to induce slow brain oscillations. Brown shares EEG spectrograms that clearly show that the brain response to anesthesia varies with age. Younger brains show strong oscillations while those of older brains show weaker oscillations. Interestingly, not all brains “age” at the same rate. By using EEG… Continue Reading
Emery Brown Part 1: Unconsciousness Under General Anesthetic is a Dynamic State
What happens to your brain when you are under general anesthesia? Dr. Emery Brown explains that under general anesthesia your brain is not turned off but is very dynamic. Electrical oscillations in the brain can be recorded using an electroencephalogram (EEG). Brown shows how oscillations induced by anesthesia interfere with normal communication between different regions… Continue Reading
Siobhan Braybrook Part 3: Cell Wall Mechanics and Growth: Beyond Plants
In her third talk, Braybrook switches gears and highlights work from her lab on cell walls found in brown algae (seaweed). Although seaweed cell walls have much in common with plant cell walls, they do have some differences. Seaweed cell walls contain much less cellulose than plants, in fact, most of the wall is made… Continue Reading
Siobhan Braybrook Part 2: Cell Wall Mechanics and Growth
For a plant seedling to grow upwards and out of the soil so it can begin to photosynthesize, it must grow more in length than in width. Growth that occurs in one direction more than in another is called anisotropic growth. How do cells do this? In plants such as Arabidopsis, almost all of the… Continue Reading
Siobhan Braybrook Part 1: The Cell Wall
Cell walls are found throughout the tree of life (even in some animals!) and in most cases they serve similar functions of strengthening and protecting cells. Dr. Braybrook’s research focuses on cell walls found in multicellular organisms such as plants and brown algae. In her first talk, Braybrook explains that cell walls are made of… Continue Reading
J. Michael Bishop: The Discovery: Evidence for a Genetic Origin of Cancer
Dr. J. Michael Bishop tells us the story of his Nobel Prize-winning discovery of cellular proto-oncogenes. Bishop was studying how the Rous Sarcoma Virus (RSV) causes cancer in chickens by expressing the viral protein called Src. Together with Dr. Harold Varmus, Bishop discovered that the chicken genome normally expresses a homolog of the viral Src… Continue Reading
Philip Benfrey Part 2: Root Form and Function
In his second talk, Dr. Benfey dives even further into the cellular differentiation pathway of plant roots. He provides an explanation of the signaling pathway that activates positive feedback and feed-forward loops that impact the organization of cells as the root develops. He also covers how roots function as they spread through soil and how… Continue Reading
Philip Benfrey Part 1: Introduction to Root Genetics
In his first talk, Philip Benfey gives an overview of root genetics and his work to identify genes that are involved in the process that takes a stem cell to a differentiated tissue. He explains how mutant Arabidopsis plants with shorter roots helped his lab understand how specific genes are expressed in plant roots, and how these… Continue Reading
Russell DeBose-Boyd Part 2: Schnyder Corneal Dystrophy: Importance of UBIAD1 in Regulation of Cholesterol
In Part 2 of his talk, DeBose-Boyd introduces a rare genetic disorder known as Schnyder Corneal Dystrophy (SCD). SCD is characterized by accumulation of cholesterol in the corneas of affected individuals, indicating that the genetic defect in SCD may affect cholesterol synthesis. Mutations in the UBIAD1 gene cause SCD – therefore, DeBose-Boyd’s lab sought to… Continue Reading
Russell DeBose-Boyd Part 1: Feedback Regulation of HMG CoA Reductase
Regulation of cholesterol synthesis is very important: cholesterol is a component of cell membranes and a precursor of steroid hormones and bile acids, yet high levels of cholesterol can be toxic to cells and can contribute to heart disease. Cells in our body obtain cholesterol one of two ways – by taking it up from… Continue Reading
Michael Dickinson Part 1: How Flies Fly: Lift
Have you ever tried to catch a flying fly only to be frustrated by their ability to evade your efforts? Then you know that many insects are extremely agile fliers. In his three talks, Dr. Michael Dickinson uses aerodynamics, muscle physiology, and neuroscience to explain how flies fly. In Part 1, Dickinson focuses on lift…. Continue Reading
Michael Dickinson Part 3: How Flies Fly: Control
In Part 3, Dickinson discusses how insects control flight. Insects have many sensors on their bodies and wings that detect odors, the polarization of light, body rotation, air movement, and more. All of this sensory information is taken in and integrated by the insect’s brain. The brain then regulates muscle function to perform the behaviors… Continue Reading
Michael Dickinson Part 2: How Flies Fly: Power
Dickinson’s second talk focuses on power. Small insect wings must beat very rapidly – much more quickly than can be controlled by the release and uptake of Ca2+ that typically regulates muscle contraction. Instead flies use two sets of stretch activated power muscles. The contraction of downstroke muscles stretches and stimulates upstroke muscles, and vice… Continue Reading