Jakarta, 10 August 2016 – The Faculty of Science and Technology kicked off the new Fall 2016 semester with a special guest talk. On Thursday, the Special Guest Talk was given by Dr. Irene S. Tobias from University of California, San Diego. Dr. Tobias talked about her research interests in the fields of materials engineering and biochemistry. This lecture was held at Sampoerna University and attended by no less than 50 people, including students from the faculty of science and technology, faculty of education, faculty of business, and university lecturers and staff.
Dr. Tobias’ Love Affairs with Biomedical Engineering
Dr. Tobias began her lecture by introducing her interest in science and engineering. She chose the department of materials science and engineering as an undergraduate at MIT because of her interest in chemistry, physics, biology, and engineering. She continued on to earn her master’s degree at the department of biomedical engineering at MIT in which she completed a master’s research on bioresorbable controlled-release drug delivery devices for treatment of urological disorders. Her master’s degree was followed with a career in the pharmaceutical industry, in which the now-Dr. Tobias was tasked to work on developing oral formulations for novel cancer therapies. She had a positive working experience in the pharmaceutical industry as a scientist, and she began to delve more deeply into how the compounds in medicine actually influence cellular signaling mechanisms at the molecular level. This interest pushed her to pursue a PhD in biomedical sciences at University of California, San Diego where she worked on the biochemical regulation of an insulin-mediated kinase, atypical protein kinase C. Atypical pKC is known to be involved in insulin-stimulated glucose transport.
Insulin is a hormone that is created by our pancreas. One of its primary functions is to induce glucose uptake from the bloodstream. Diabetes is characterized by the excessive presence of glucose in the bloodstream, which can be very dangerous if it is not well managed. Dr. Tobias’ PhD thesis modeled how insulin signaling actually works at the molecular level. Insulin is secreted from the pancreas and moved to the receptors on cell surfaces. A protein receives the signal from these receptors and go on to transmit other signals to take up glucose molecules into tissue, where they can be stored for future energy expenditures of the muscles. Dr. Tobias studied these signaling mechanisms in depth, how they work, how to modulate them, how they would lose their ability to respond.
Encouraging the Lazy Enzyme
Protein kinase is an enzyme that catalyzes the transfer of phosphate groups from high-energy, phosphate-donating molecules to specific substrates. This process, known as phosphorylation, can change the protein activity or sometimes its localization so it’s very important in cell signaling. Kinases are commonly misregulated in several diseases, such as cancer and diabetes. Dr. Tobias worked on serine threonine protein kinases, which are specific for either serine or threonine amino acid presence in protein substrates. They are atypical pKC and Akt that she had compared using different cell signaling models found in the body of literature. Akt and atypical pKC are both known to be involved in insulin stimulating glucose transport events. Atypical pKC can often be hyperactive for diabetic liver, while Akt is still defective and they may have a very different mechanisms of activation and downstreet signaling, which can be different in different tissues. Her research was really asking the question of what the mechanism of atypical pKC is in response to insulin. Dr. Tobias created a model that separated out the mechanisms that activate atypical pKC, which separated out the mechanisms that activate atypical pKc from those that activate Akt. pKC is referred to as a “lazy enzyme” because it has very slow catalytic activity even though it is functional.
Dr. Irene Tobias closed her special guest lecture by explaining that oral drug formulations could be developed to potentially target diabetes (and other diseases). One of the challenges is hyperactivity of insulin uptake in the liver as opposed to uptake in the muscle. She emphasized the importance of fundamental scientific research to properly understand all the underlying mechanisms behind different physiological and medical functions, so that any treatments or applications may be more accurately targeted.
By Shinta Dewi Ariantika, Science Laboratory Coordinator at the Faculty of Science and Technology, Sampoerna University