iBiology Videos

Chow discusses Illumina NGS Sample Preparation. He goes over DNA and RNA preparation, bead-based (Ampure or SPRI) cleanups, and sample quantification and quality control.

Chow gives advice on purifying DNA samples using magnetic beads and on determining the quality of your nucleic acid sample using an Agilent Bioanalyzer.

Chow gives advice on purifying DNA samples using magnetic beads and on determining the quality of your nucleic acid sample using an Agilent Bioanalyzer.

In the past decade there has been an amazing change in the efficiency of DNA sequencing. Using traditional Sanger sequencing, the human genome project took 20 years and cost $3 billion. Current next generation sequencing methods allow a human genome to be sequenced for $1000, in 48 hours!  In this talk, Eric Chow explains the chemistry behind next generation sequencing, and describes how the next gen sequencers detect and display results. The most commonly used Illumina sequencers are image based and detect the addition of fluorescently labelled nucleotides. Chow also describes two different next generation sequencing technologies which provide benefits such as much longer reads but with downsides such as higher error rates. Chow finishes the talk with some insights into medical applications of next gen sequencing such as much less invasive prenatal testing or cancer detection.

Course Directors A. Malcolm Campbell, Kimberly Tanner, and Bill Wood talk about the reasons why we need to reform undergraduate biology education and why they got involved in the Scientific teaching Series project.

When it comes to neuronal regeneration, very little is known about the ability of dendrites to regrow following trauma. In this lecture, Dr. Thompson-Peer describes her discovery of fundamental principles of neuronal regeneration, particularly of how neurons respond to and recover from dendrite injury. She also describes how this work is laying the foundation for a vastly understudied field of science.

This talk is part of the Young Scientist Seminars, a video series produced that features young scientists giving talks about their research and discoveries.

Tanaka expands on her work on signaling in axolotl limb regeneration. She explains how her lab used the technique of expression cloning to identify several factors required to trigger the cell migration and proliferation required for regeneration.  Tanaka was also curious about what signals differentiate a wound from an amputation. It was known that regeneration required the presence of nerves as well as the interaction of anterior and posterior limb tissue. Tanaka’s lab was able to show that the expression of the signaling molecules SHH, on the posterior side, and FGF8, on the anterior side, of an amputated limb were enough to sustain regeneration. Identification of these signaling molecules has advanced our understanding of limb regeneration in vertebrates.

Among four limbed animals, salamanders are the champions of regeneration.  They can regenerate an amputated leg or tail, as well as various internal organs.  In her first talk, Elly Tanaka explains that axolotl limb regeneration is an excellent system to study the cellular and molecular mechanisms of limb regeneration in vertebrates. Tanaka and her colleagues have shown that the regenerating limb has positional memory. For example, an amputated hind limb with regenerate a hind limb and not a forearm. They also have identified the key signaling molecules involved in determining positional identity.

Sykes provides an overview of xenotransplantation, the use of organs or grafts from other (non-human) species. She outlines the challenges encountered with cross-species transplantation, and how scientist have been able to overcome these difficulties. Sykes and other laboratories are exploring the use of miniature pigs for xenotransplantations to humans. Sykes shows the outcome of xenotransplantations performed between different species (e.g. rat to mouse or pig to baboon), and what scientists have learned from these results.

Dr. Megan Sykes provides an introduction to the field of organ transplantation and discusses the immunological responses associated with this procedure. Rejection is a major limitation to the success of transplantation. Sykes explains what causes rejection episodes in different types of transplantation, and outlines what we can do to prevent this from happening.