In this blog post, we’ll explore the emergence and development of synthetic biology—which aims to engineer and create living organisms based on a physical and chemical understanding of the nature of life—and examine how concepts of circuit and system design from electrical engineering are converging with the life sciences.
Suppose we are conducting a fruit fly cloning experiment in a biology lab. Let’s say we have two fruit flies with identical nucleotide sequences, and both have undergone exactly the same biological developmental process, including exposure to the same environmental factors. Assuming that all biological processes and constituent materials forming these individuals are identical, one of them suddenly dies at this very moment for some reason. This raises an intriguing question: What is the difference between the two fruit flies—or between what was once a living organism and what is currently a living organism? Should a living organism be regarded as nothing more than a mere collection of molecules? What is the difference between the living and the non-living? If we understand life itself, how can we utilize that understanding?
We have confronted the question “What is life?” in various ways. This question is not limited to fruit flies alone but applies to all living beings. In fact, various discussions and studies have been conducted to answer this question, and traditionally, this has been the domain of biology. However, there is one perspective that has caught my attention. Just because current physics and chemistry cannot clearly explain biological phenomena does not mean that these sciences will never be able to elucidate such issues in the future. I believe that this very perspective has opened up a new research horizon—one that moves beyond the research methodology biologists have traditionally adopted (namely, first observing biological phenomena and then seeking their causes) to explain biological phenomena based on a molecular-level understanding of physics and chemistry. It is already widely known that Schrödinger’s views served as the starting point for Watson and Crick’s understanding of the structure of DNA, and the influence of this perspective can also be seen in the fact that today’s life sciences have evolved into a convergent discipline that integrates various fields—such as statistics, physics, chemistry, and computer programming—rather than remaining an independent discipline of biology alone.
However, a trend has recently emerged that goes a step further than this perspective. Synthetic biology is emerging as a field that incorporates an engineering perspective into the foundation of life science understanding. Synthetic biology is a field that applies engineering design principles, standardization, modeling, and other methods to design and combine genes, proteins, and other components of living organisms to create biological systems that perform desired functions. Therefore, it requires not only biological knowledge but also logical and systems-based thinking that has evolved in fields such as mechanical engineering, electrical engineering, and electronic circuits. In particular, DNA synthesis, the standardization and abstraction of biological components, and the design of genetic circuits share similarities with the methods used in electrical engineering to design circuits and assemble components. At MIT, research and education have long been conducted to develop synthetic biology as a field focused on the engineering design and assembly of biological components. Even today, synthetic biology is treated as an independent research area, with ongoing research into the manipulation of DNA, RNA, and proteins; the design of genetic circuits; and the design of metabolic pathways. Gene standardization is an approach that goes beyond simply conducting experiments from scratch each time a gene from another species is introduced; instead, it involves accumulating information about components and their functions that can be used in specific biological systems and enabling their reuse. In line with this trend, iGEM, which originated at MIT, has evolved into a key initiative for spreading synthetic biology throughout education and research. iGEM began as a course in which students designed biological systems and has since evolved into an international synthetic biology competition in which students from around the world continue to participate annually. The emergence of this field is rooted in the reality that, despite the accumulation of a vast amount of life science research data worldwide, it remains difficult to fully explain the origins of biological phenomena, as well as in the desire to engineer this accumulated data for practical applications.
Therefore, it is necessary to clearly examine the specific areas where electrical engineering converges with biology to play a role. Synthetic biology involves research that maps biological functions—such as gene expression, protein metabolism, and signal transduction within living organisms—to the operation of analog circuits. This approach allows researchers to derive circuit design ideas for specific mechanisms occurring within cells or, conversely, to identify faulty components or biologically unvalidated elements within cellular structures through circuit analysis. In fact, research in synthetic biology involves modeling the process by which cells detect external stimuli, process information, and trigger specific responses as a circuit-like system, as well as designing gene networks like logic circuits. At MIT, research has been conducted using synthetic gene networks to enable cells to detect and process signals and perform specific functions, utilizing concepts from both analog and digital logic circuits. For example, researchers can propose new forms of biological analog computing by utilizing existing analog computational functions within cells, or identify mis-expressed gene segments through circuit simulations to aid research into treatments for cancer, immune disorders, diabetes, and genetic diseases. Furthermore, research is underway to supply power to medical electronic devices using technologies such as biofuel cells that utilize the energy and glucose produced during glycolysis, with the long-term goal of reducing the reliance of implantable medical devices on batteries. However, these technologies are still in the research phase and face challenges that need to be addressed, such as ensuring stable output, longevity, and long-term use within the human body. Furthermore, we can envision a future where electrical engineering and life sciences are even more closely integrated through technologies such as electronic devices that exchange information with neurons or systems that measure and process electrical signals from biological systems.
The scope of electrical engineering and the benefits we derive from it are so vast today that they are impossible to fully describe. In particular, as various disciplines converge based on a unique academic foundation, this scope is expected to expand even further in the future. At MIT, biological engineering is treated as a distinct engineering discipline, with research in synthetic biology, systems biology, and bioinstrumentation linked to various fields, including electrical and computer engineering. Similarly, Stanford and UC Berkeley are developing synthetic biology and biotechnology into interdisciplinary research fields that utilize engineering design and computational methods. Recognizing that the role of electrical engineering is growing daily amid efforts to accurately understand life and utilize it effectively and responsibly, it is necessary to actively engage in various academic fields, including synthetic biology.
