Source: Produced for Teachers' Domain
This video produced for Teachers' Domain profiles Karmella Haynes, a post-doctoral researcher working in the emerging field of synthetic biology. Karmella explains how she uses biotechnology to build living machines, or devices, from genes. She then puts these devices into the cells of living things and studies the results. Haynes hopes that one day the devices she's working on will carry out complicated functions in human bodies, such as curing a disease. The video demonstrates how Karmella is using synthetic biology to detect cancer cells before they spread.
Synthetic biology is the science of taking different parts from nature—specifically, DNA and protein—and putting them together in new and useful ways. Much like engineers build industrial equipment from machine parts, synthetic biologists build living devices from biological parts. These "devices" are made through modifying pieces of DNA—splicing genes together with instructions to perform some new function inside a living organism. Yet, to give an idea of their powerful real-world potential, consider that researchers can already use synthetic biology to solve mathematical problems, and are fast developing applications in medicine, energy, agriculture, and the environment.
Synthetic biology relies on complex devices that enable a living thing to carry out complicated functions that it does not normally do—such as helping a body cure itself of a disease. Synthetic devices can also help detect abnormalities in cells early on and observe their division. For these devices to be effective, they must actually become a self-sustaining part of a living system—that is, capable of eating, replicating, and moving.
For living devices to perform as they're intended, their synthesized proteins need to access a cell's nucleus to give it instructions for making the desired proteins by turning on very specific genes. To enter the nucleus, the proteins need to have a special part—called a nuclear localization sequence—that allows them to cross the nuclear membrane. Karmella explains how this could work:
[For] example, we have a gene that gets turned on in the presence of a drug. In my system, the drug activates the gene.... Because I took the protein and fused it with a nuclear localization sequence, the protein can go back into the nucleus and turn the gene back on again. So, now what I have is a constant cycle of gene activation, and my device can actually keep turning itself on.
Karmella Haynes has always had an interest in science, but not to the exclusion of other interests. She continues her lifelong love of painting and uses creativity in her scientific work. The following excerpts describe how Karmella was drawn to genetics and, eventually, to synthetic biology, because of their relationship to mathematics.
When I was in high school, I enjoyed math a lot. I also enjoyed biology very much, especially when I started learning about DNA.... Once I learned that biology could be broken down into four letters, A, T, C, and G, which make up DNA, I got really excited about biology and I saw that there was something mathematical about it.
When I was introduced to synthetic biology, I actually relived the initial excitement that I experienced when I was introduced to DNA and genetics back in high school. I learned about synthetic biology after I had earned my Ph.D.... and then all over again, I saw that biology could be broken down into pieces and—not only that—that those pieces could be put together to build cool, new things. That got me really excited.