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Continuum 2006.Indd ContinuUM Newsletter of the Department of Mathematics at the Uni ver si ty of Mich i gan 2006 Mathematical Modeling View from the in Sleep Gene Research Chair’s Offi ce The interdisciplinary research of As- Tony Bloch sistant Professor Daniel Forger is receiving The Department of Mathematics has wide recognition from the scientifi c com- had a busy and productive year. During munity. Forger, who joined the Department this time, many of our accomplished fac- of Mathematics this year in the Mathemati- ulty and excellent students received various cal Biology program, works in the area of honors, some of which are detailed else- circadian rhythms and the biological clock. where in this issue of ContinuUM. The core of his thesis involved the con- struction of a detailed biochemical model One should be cautious about taking of the mammalian intracellular circadian outside rankings too seriously. That said, clock. His model is now the most detailed we are pleased to report that our Depart- and realistic one available. mental ranking in the US News and World Report rose from 9th in 2002 to 7th in Forger used his model in recent re- 2006, tied with the California Institute of search with collaborators from the Univer- Technology, New York University and Yale sity of Utah’s Huntsman Cancer Institute. University. It is a pleasure to be associated The studies showed that the effect of a mu- with such a distinguished and exciting De- tation in a key gene involved in the regula- partment. tion of sleep and wake cycles in mammals works in the opposite way from what was The current size and quality of the De- previously thought. A paper on the topic partment is refl ected in the amazing range appears in the July 11 issue of the Proceed- and scope of our activities. During the ings of the National Academy of Science. 2005-2006 academic year we had more than 180 visitors. Special events for the The bodies of mammals know what Daniel Forger year included weekly colloquia by distin- time it is by constantly measuring the con- mutation is present. “I had this prediction guished mathematicians from around the centration of a protein called PER in the for a year or two,” Forger said. “Basically, world. Department members organized body. Drug companies continually investi- people said this is ridiculous, you’re a math- numerous conferences on varied subjects: gate ways to manipulate the level of PER in ematician, what do you know…” representation theory, future directions in the body to treat sleep disorders, and other 3-manifolds (honoring Peter Scott), recent disorders impacted by biological clocks. Forger's computer models solve a sys- tem of over 50 differential equations. This progress in birational geometry, math- The degradation of PER is regulated large number of equations comes from the ematical biology (see story on page 3), and by another protein, called CK1e, whose many states of PER and the fact that many geometric function theory. There was also production is controlled by the gene casein other proteins can bind to PER to regulate a lecture series in algebraic geometry, and kinase 1, or CK1. It was initially thought its behavior. Every time a new binding part- Mel Hochster’s Distinguished University that a mutation called “tau” in CK1 led to ner or state is included, the number of equa- Professorship lecture entitled “The Un- the production of defective CK1e proteins tions signifi cantly increases, perhaps even expected Usefulness of Prime Numbers.” that break down PER more slowly than is doubling. He also validated this prediction We have established a new web page to normal, causing the protein to accumulate with a simple linear model for which one document some of our events and lecture in the body. This buildup was thought to can derive a formula for the effect of tau on notes at http://www.math.lsa.umich.edu/ speed up a mammal’s internal clock, caus- the predicted period. lecturesmath/index.html. Please feel free ing it to have shorter days. to browse the information. Forger met David Virshup, M.D., while Forger’s computer models had always giving an invited talk at the University of As far as the faculty are concerned, we said that the opposite of the prevailing Utah. Virshup’s previous research was on currently have 68 regular tenured/tenure- thinking should be true—that the PER pro- track members, 7 other non-tenure-track tein should degrade more quickly when the Continued on page 2 Continued on page 2 Notes from the Chair Our development and fund raising ef- Mathematical Modeling (continued from page 1) forts have been successful thanks to the in Sleep Gene Research generosity of our loyal alumni. Our an- (continued from page 1) members, and 49 three-year post-doc fac- nual alumni fund raising letter consistently ulty positions. Faculty members of the raises a much needed $16,000 to $20,000. the gene involved in circadian rhythms and Department currently hold more than 153 This year these funds allowed us to provide its role in cancer development. Their ex- federal grants. scholarship support to 2 undergraduate periments had also suggested that genetic The student body comprises 140 gradu- students and summer support to 5 graduate mutation caused the protein to degrade ate students and approximately 285 math students (see story on page 16). Other fund more quickly. Virshup suggested they test concentrators. In the Fall 2005 term, 6596 raising allowed us to continue our affi lia- Forger’s simulation. students were enrolled in math courses. In tion with the Inquiry Based Learning pro- This new study proves their hypothesis: the winter term there were 4560 such stu- gram, a program which funds exciting new The tau mutation doesn’t slow down PER dents. There were 90 undergraduate math innovations in teaching. degradation—it speeds it up. Not enough majors who graduated this year, and 29 We are extremely grateful to all those PER leads to shorter days in animals af- new graduate students will be starting their who with their contributions help to make fected by the gene mutation. programs in the fall of 2006. our Department an excellent place for teaching, learning, and research. The researchers took cell cultures and observed that for those with the mutated UM Mathematics Department We are looking forward to a dynamic gene, the protein only took a couple of is now tied for 7th in U.S. new academic year with extremely exciting hours to degrade. For the normal gene, it News and World Report programs. There are several exceptional took 8-10 hours. events planned. One highlight will be our rankings among U.S. public colloquium which, this year, promises to be These fi ndings will have an impact Universities truly extraordinary: no fewer than 7 Fields on the development of new drugs for the Medal winners will be giving lectures! treatment of disorders such as insomnia, depression, and others that rely on the I have every confi dence that we will Another highlight will be the Ziwet and regulation of the inner body clock. continue from strength to strength even Rainich lecture series to be given in the though the Department continues to face fall by most distinguished mathematicians. Forger joined the Department of Math- the perennial challenges that have been Jerrold Marsden of Caltech will give the ematics in September 2005. He received mentioned here in previous years. In par- Ziwet Lectures in September. Philip Hol- his Ph.D. in Mathematics from the Courant ticular, unrelenting budget pressures con- mes of Princeton will present the Rainich Institute at New York University, and was tinue to be a problem in many areas, and lectures in November. Everyone is invited a Sloan Foundation Fellow at NYU in especially in the area of faculty retention. and encouraged to attend these memorable Computational Molecular Biology. From This results from the fact that the other best events, some of which are highlighted on his earliest contact in the Department, math departments in and out of the country page 17. Additional information on all Forger impressed his colleagues with his keep trying to lure away our many out- Department activities can be found on our knowledge, energy and enthusiasm. standing faculty members. website www.math.lsa.umich.edu. “Michigan is an ideal place to model We would like to remember here sever- circadian clocks,” says Forger. “Other al Department members who are no longer great modeling/experimental studies are with us: Professors Emeriti James Wen- being conducted by members of the Math- dell and Don Higman, and former faculty ematical Biology Research Group within members Raoul Bott, Hans Samelson and the Department targeting problems in areas Robert Thrall. Also, our much loved former Math Problem like infectious disease and cancer. Discus- secretary who was active in the Department Twenty-four delegates sit around sions about common modeling techniques until she died, Ethel Rathbun, passed away a round table. Two delegates can within the group are invaluable to model last fall (see story on pages 12-13). We speak to each other if at most four development as are discussions with other will miss them all. people sit between them. After Department faculty on how to accurately analyze and/or simulate models. It is also Peter Hinman and Pat Shure retired this a break each person sits down important to mention the large amount of year (see story on page 6). We wish them again, not necessarily in the same clock research being done on campus in- all the best for the future, and we thank seat as before.
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