Academics

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A series of exciting formal talks were held in the fall of 2006 on topics ranging from neurodegeneration to intelligent design.  These presentations, held for the first time on such a regular basis throughout the semester, were launched by Eukaryon, Tri-beta, the Biology Department, and the Center for Chicago Programs.  Students were exposed to the latest research of distinguished scientists in fields such as neurodegeneration and psychology.  Many students majoring in biology, psychology and chemistry attended these talks.  The presentations also attracted students from the social sciences and humanities

The interactive nature of the presentations added to the rich liberal arts education at Lake Forest College and emphasized the importance of out-of-classroom learning experiences. These presentations highlighted the mission statement of the Biology Department to help "students embark on hypothesis-driven journeys of discovery where answers are found not in textbooks, but in the lab and the field". All of the speakers spoke in simple language, and welcomed questions from the audience, which also included professors and on occasion members of the public. A brief summary of the six talks is given below:

Stress and Aging in Neurodegenerative Disease

Dr. Richard Morimoto, Bill and Gayle Cook Professor of Biology, Northwestern University

Have you ever wondered if stress affects the 30 trillion cells of your body? What happens when you are stressed? Can stress increase your chances of getting neurodegenerative diseases, like Alzheimer’s disease or Parkinson’s disease? Dr. Richard Morimoto, professor of biochemistry and molecular and cell biology at Northwestern University, addressed a packed auditorium of students in the first of a series of six talks.

Specifically, the particular kind of stress being spoken of was physiological stress, which includes a number of factors like temperature, viruses, genetic factors, and heavy metals to mention a few. Primarily, stress affects a diverse class of molecules called proteins, whose function depends on their natural shape or conformation. At the molecular level, cells in our bodies respond to a plethora of "stressors" like temperature and lack of nutrients, using special proteins called receptors. These receptors induce different protective responses for the varied stressful stimuli our cells experience. They can initiate mechanisms enabling the cell to survive or mechanisms to commit suicide through a systematic process known as programmed cell-death, or apoptosis.

On average, our cells contain 10¹³ proteins!  Many of these proteins functions in multiple pathways.  Different proteins are also assembled into protein machines, which help carry out cellular processes.  Dr. Morimoto explained that in order to make so many proteins so rapidly and with diverse functions, the cell has protein quality control machinery which makes sure that proteins are folded correctly, have the right shape, and are functioning well.  Those that do not meet these requirements are degraded.  When proteins are synthesized in our cells, about 10% have missense mutations, which occurs when a protein building block is misplaced in the sequence of building blocks.  Thus, the most important process in the cell is error prone.  Proteins with missense mutations, as a result, fold differently and may have different functions.  Lightening up the mood in the auditorium, Dr. Morimoto compared our cells to a Ford motor plant, rather than a Toyota motor plant!

Proteins somehow know how to fold by themselves and we are yet to discover how and why this process happens. Misfolded proteins cause "proteotoxic stress" due to their altered shape and function. These misfolded proteins, if not degraded by the cell, can be toxic, which is the major hypothesis for the cause of some neurodegenerative diseases, like Huntington’s, Alzheimer’s and Parkinson’s. To prevent misfolding from occurring, cells have a special class of proteins called chaperones, which help with correct folding. Explaining how proteins can change shape when thermally heated, Dr. Morimoto used an example of making eggs where heating up the protein (or eggs), changes its shape, form, and function. We certainly don’t want that happening in our brains! Thankfully, heat shock factors, or HSFs, help cells regulate protein’s shape in cases of stress. As we age, these HSFs do not function as efficiently, thus increasing "proteotoxic stress" in our cells and subsequent toxicity.

Dr. Morimoto uses C. elegans to study HSFs. He explained that this nematode is a good model system to study diseases as each organism has only 959 somatic (non-gonadal) cells and 302 nerve cells. Further, the worms are transparent and the fate of each cell in the worm has been determined. C. elegans have about 160 chaperones. He showed data from his lab, where knocking out a heat shock factor, HSF-1 led to the formation of many aggregates in the worm nervous system. Overexpressing lots of HSF in the worms gave them a longer life span!

This presentation tied in concepts from a number of biology courses, including Organismal Biology, Diseases around the Globe and Cell and Molecular Biology. The importance of protein shape and its relationship to the proteins’ function was a review for students of Organismal Biology. Students who had taken Diseases around the Globe had a clear idea of the diseases Dr. Morimoto mentioned, while Cell and Molecular Biology students could easily recall protein formation in the cell!

Junior Sina Vahedi, thought that the presentation was very good but he would have wanted to see more data and details about the experiments. However, Sina understood that the talk’s lack of experimental detail made it more accessible to the many non-science majors in the audience.

Dr. Morimoto’s presentation was simple and easy to understand. It explained the connection between stress, protein misfolding, and neurodegenerative diseases. Dr. Morimoto’s sense of humor, calm disposition, and the tone and pace of his voice made this presentation both educational and enjoyable.