MICHIGAN WAS HONORED LAST FALL WHEN THE MACARTHUR FOUNDATION NAMED NOT ONE, BUT THREE U-M RESEARCHERS TO ITS PRESTIGIOUS LIST OF MACARTHUR FELLOWS. WE SHARE THEIR IDEAS HERE—READ ON AND BE INSPIRED.

Every fall, 20 to 25 people in the United States get an unexpected phone call with some life-changing news: They have been selected to receive a $500,000, no-strings-attached fellowship from the John D. and Catherine T. MacArthur Foundation.

Last September, U-M researchers Tiya Miles, Melanie Sanford, and Yukiko Yamashita were three of the 22 MacArthur fellows selected. Only Harvard could claim as many recipients in 2011. They are now members of an exclusive group of 850 individuals—24 total from U-M—who have received the prestigious award since the program was established in 1981.

Receiving a MacArthur Fellowship is a notable honor because it is enveloped in mystery. No one can apply for the award. Names of the individuals who nominate prospective fellows and the members of the committee who select them remain confidential. And recipients always learn about it with that unexpected phone call.

Journalists sometimes call these awards “genius grants,” but MacArthur Foundation officials maintain that being extremely smart is not enough to make the cut. What’s more important, they say, is creativity, originality, and the potential to make an important contribution to the future. This year’s U-M MacArthur fellows possess all three of those qualities.

THE HISTORIAN

Tiya Miles is fascinated by America’s past and its relationship to the problems and issues we face as a multicultural society today.

She has a special interest in the early 1800s, when people from three different cultures—European American, African American, and Native American—lived together in the southern United States during a period of major economic and social change. Miles maintains that the convergence of those three cultures laid the groundwork for America’s future. She sums it up in seven words: No land, no labor, no United States.

“The very land this country was built on is indigenous land,” explains Miles, a professor of history and American culture and a professor and chair of the Department of Afroamerican and African Studies. “The labor that was necessary for this nation’s early development was produced by Native Americans who were enslaved and African Americans who were enslaved.”

People have different reactions to the fact that America was built on slavery. Some want to preserve an idealized version of the past. Some just want to forget it ever happened. But Miles says it’s important to understand this crucial time and place in American history. Because what happened then— or, more accurately, what people believe happened then—is still with us today. The legacy of slavery affects our ability to bridge racial, class, and cultural barriers.

Miles describes herself as a historian who specializes in African-American, Native American, and women’s history. While she is the author of many scholarly articles, the MacArthur Foundation cited her books, which she writes for a scholarly and public audience.

Her first, “Ties That Bind: The Story of an Afro-Cherokee Family in Slavery and Freedom,” was published in 2005.

It tells the story of Shoe Boots, a Cherokee warrior and farmer, and Doll, an African-American woman who was his longtime companion, the mother of his children, and his slave.

Five years later, Miles’ second book, “The House on Diamond Hill: A Cherokee Plantation Story,” was published. It tells the story of wealthy Cherokee chief James Vann and his son, Joseph. James Vann was the largest slaveholder in the Cherokee Nation and among the largest slaveholders in the state of Georgia.

The Chief Vann House is a state historic site and frequent tourist destination. When Miles first visited the site, she was shocked to find no information about the more than 100 African and African-American slaves who lived and worked at Diamond Hill. In fact, the Vann family was one of the largest slave-owning families in Georgia during this time in the state’s history.

“African-American history was completely invisible at the site,” says Miles. “It wasn’t acknowledged, because from what people remembered, there was none of it. But this was a plantation where the majority of the population was black.”

Miles returned to Diamond Hill several times and showed a video tour to her class of U-M undergraduate students. Those students researched and wrote a booklet about the history of slavery at Diamond Hill and donated it to the Chief Vann House historic site. The booklet was the beginning of what Miles describes as “an unexpected and rewarding journey” that led to a positive collaboration with the site’s staff and a new exhibit about African-American life on the plantation.

The invisibility of slaves at Diamond Hill is just one example of many widely accepted myths, stereotypes, and misperceptions about African-American and Native American history that Miles tries to address in her research and writing. In her next book, she wants to take on another myth, the one that says slavery was illegal and didn’t exist in northern states. “A lot of Michigan’s history is actually pretty murky when it comes to slavery,” Miles says. She plans to focus on court cases involving slavery in Detroit at the turn of the 19th century.

To Miles, it’s about more than the pursuit of historical accuracy.

“I’m interested in being a memory keeper for multiple communities and for our society,” she says. “I want to go back into the past and look for stories that are particularly telling in terms of what they show about the human experience. I hope the stories I find and tell will help create change.”

THE CHEMIST

In the world of organic chemistry, carbon and hydrogen are like Romeo and Juliet: No matter what happens, they want to be together. Once these two elements bond together, it takes large amounts of energy to separate them. Or at least it did, until Melanie Sanford developed new catalysts that made it easier for carbon and hydrogen to separate and form new chemical bonds with different atoms. Like all catalysts, the metalbased catalysts Sanford develops help facilitate a chemical reaction without taking part in it.

Her creative, novel approach to organic synthesis is the reason Sanford was selected to receive a MacArthur Fellowship.

“Carbon-hydrogen bonds are in products we use every day, like shampoo, food, perfume, gasoline, and pharmaceuticals,” says Sanford, the Arthur F. Thurnau Professor of Chemistry. “What we do is replace the hydrogen with other atoms in a selective way.”

Selectivity is important because the complex molecules she works with can have up to 100 carbon-hydrogen bonds. “To make something useful,” she says, “you have to be able to pick out just one bond and turn it into a new working group.”

The ability to manipulate these bonds could be especially useful in the pharmaceutical industry, where medicinal chemists develop and test new experimental drug compounds. A small change in the chemical structure of one of these compounds can mean a big improvement in the drug’s effectiveness or a reduction in toxic side effects.

“Let’s say someone has a molecule that shows good anti-cancer effectiveness, but it has some toxicity,” Sanford explains. “We can take that compound and quickly make a whole series of derivatives with different groups—a fluorine or bromine or iodine—that can be screened for biological activity.”

Sanford’s work also has applications in a new approach to industrial chemistry called green chemistry. The goal is to reduce the number of steps required to produce a chemical compound. Each additional step in the process takes more energy and creates more chemical byproducts, which are often toxic and cost money to dispose of properly. Using her catalysts, Sanford can reduce a 10-step chemical reaction in the laboratory down to a single step.

Recently, Sanford and her research team have started developing a series of catalysts to take carbon dioxide gas, or CO2, and convert it into methanol, an energy-rich liquid that can be burned as a fuel. CO2 emissions are a major cause of global warming. “Instead of releasing CO2 into the atmosphere, it could be recycled and used as a fuel, in the form of methanol,” Sanford says.

She is also working on new types of chemistry and catalysts to convert methane, the major component of natural gas, into methanol in just one step. The current process requires two steps: one to convert methane to syngas and another to convert syngas to methanol. The two-step process requires enormous amounts of energy and a large, expensive conversion plant. A one-step process would require less energy and be far less expensive.

“The methane-to-methanol and CO2-to-methanol (conversions) are both huge global problems of our time,” Sanford says. “If we can make a contribution to solving either of those problems, it would be very significant. We are making progress, but are still very, very far away from something that would be practical.”

Sanford appreciates how important the applications of her research could be someday, but right now she is more interested in figuring out how the chemistry works.

“We’re not just interested in developing a new reaction that people can use to do X, Y, and Z,” she says. “We’re interested in understanding, on a fundamental level, how do the molecules come together? What is the roadblock or rate-limiting step that slows the process down? How can I design a catalyst to address that step?”


THE BIOLOGIST

The human body contains about 90 trillion cells, and almost every one of them can trace its ancestry back to the division of an adult stem cell.

All cells divide in a process called mitosis. But unlike ordinary cells, the two cells that are created when a stem cell divides are not identical. One is a replacement stem cell that remains in the “stem cell nursery,” called a niche. The other, called a daughter cell, leaves the niche and continues dividing to produce specialized cells, such as blood or muscle cells.

An adult stem cell’s most important job is maintaining the right balance between renewing the supply of stem cells in the niche and producing a steady supply of daughter cells to replace specialized cells that wear out and die. But how does the stem cell know when it’s the right time to divide? And when a stem cell divides, what determines which of its offspring will remain a stem cell and which become a daughter cell?

These are questions that keep stem cell biologists like Yukiko Yamashita awake at night.

Yamashita, a research assistant professor in the Life Sciences Institute, was thrilled and honored to be named a MacArthur Fellow. But she’s not interested in the fame and media attention that come from making a big scientific discovery. She just wants to understand cells and the “beautiful strategies” they use to communicate. “For me, it’s all about appreciation,” she says. “If I can understand any of the strategies nature has evolved, I will be very happy.”

There’s a tantalizing list of possible applications for stem cells in medicine: new ways to treat or prevent cancer, cell-based therapies for diabetes and neurodegenerative diseases, regenerating or repairing damaged organs and tissue. But before scientists can harness the potential of stem cells, they have to figure out how they work.

Yamashita studies how stem cells divide and differentiate to produce sperm in the reproductive tracts of male fruit flies. She’s trying to understand how a complex network of signals from surrounding cells and proteins controls the stem cell division process. It’s uncharted scientific ground that requires meticulous step-by-step research.

One of her first discoveries involved the role of centrosomes—cellular structures that control the formation of the spindle apparatus that separates duplicated chromosomes during mitosis. Yamashita and her research team found that the position of the centrosomes is critical to the entire process. Until both centrosomes are lined up exactly perpendicular to the stem cell niche, the cell can’t make a spindle and mitosis can’t begin.

“One centrosome is anchored to the stem cell niche, while the other lines up exactly opposite it,” says Yamashita. “If the centrosomes aren’t aligned, the cell goes into a holding pattern called cell cycle arrest.”

Since her original discovery, Yamashita and her research team have identified several proteins involved in centrosome orientation. One, called centrosomin, determines which centrosome will lock onto the stem cell niche and become the mother centrosome. Another, called cyclin A, is released to the nucleus to trigger mitosis only when the centrosome locks into the correct position. But how does the position of the centrosome cause the release of cyclin A?

“We’ve found a protein located in a tiny area of the stem cell membrane just next to the niche,” says Yamashita. “We think it may be a docking site. Once the centrosome locks onto this protein, we believe it triggers a signal that releases cyclin A, so mitosis can begin.”

Centrosome misorientation also helps explain why old fruit flies produce less sperm than young flies, according to new findings from Yamashita’s research team. As the number of stem cells declines with aging, partially differentiated daughter cells move back to the niche to increase the supply. Daughter cells aren’t as good at aligning properly, according to Yamashita, which means fewer new stem cells are produced.

Yamashita also found that old flies produce lower levels of a protein called Cdc25, a master regulator of mitosis. When she added Cdc25 to aging fruit fly testes, the stem cells started dividing again. But there was a problem: the tissue developed tumors.

“It suggests that when stem cells decline with aging, it’s to prevent the development of tumors,” she explains. “Aging may be a tumor-suppressive mechanism. If the choice is to stay young or get cancer, you may not want to stay young.” .

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Sally Pobojewski is a freelance science writer who lives in Chelsea, Michigan.