Sid Altman

Molecular Biology

Discovered catalytic RNA, for which he won the Nobel Prize in 1989

"Don’t worry if things change. Just do what you do best."

The year is 1970 and it’s an unusually warm June day. Sid Altman is worried. He has no job prospects and he has little to show for a year of work in Francis Crick and Sydney Brenner’s laboratory in Cambridge, England. Crick was the co-discoverer of DNA (DeoxyriboNucleic Acid), the molecule that encodes the genetic information that tells cells how to function and grow. It’s an incredible honour for Altman to have been invited to this famous laboratory. At the moment, it’s probably the best place in the world for genetic research, but Altman has only two weeks left before he must leave. And he has no idea where he will go or what he will do next.

Altman is working on mutant cells with malfunctioning t-RNA (transfer RiboNucleic Acid)—a substance that is part of the machinery in a cell that decodes instructions in DNA. DNA and RNA are long twisty chain-like molecules. (For more information about these, see Chapter 16 on Michael Smith.) For about the thousandth time, Altman picks up a glass plate on which there is a thin layer of gel. But this plate is special. Altman is trying a new experiment, something no one has ever tried before. If he can just isolate a special type of RNA called precursor-RNA it would explain a lot about the process of reading the genetic code from a strand of DNA.

After putting a few drops of material prepared from the mutant cells onto the gel, Altman places the plate into a strong electric field. This technique, called electrophoresis is a standard method for separating chemical compounds. The electric field causes different compounds to move across the gel at different speeds. Altman waits several hours, and then lays photographic film on top of the gel. Tiny amounts of radioactive tracer atoms in the RNA emit X-rays that will leave characteristic bands on the film.

With a friend, Altman takes this latest piece of film into the darkroom to develop it. Within minutes the two young scientists both see the same thing. It’s just a white splotch on the negative but it gives Altman one overwhelming thought: “Now I know I can ultimately get a job.” He had taken the first step in a long series of experiments that would ultimately lead to the discovery of catalytic RNA.

Altman was hired for one more year in Crick’s lab, then became a biology professor at Yale University in USA. His work over the next two decades lead to the discovery of catalytic RNA and resulted in his winning the Nobel prize in 1989. He is still working on aspects of the same molecular biology system today.

As a young scientist ...

Sidney Altman grew up in the Notre Dame de Grace suburb of Montreal. As a boy he loved books. He liked sports and writing, too, but the library was one of his favourite places. He read widely, from novels to books on sports and science. “I read everything I could get my hands on,” he remembers.

When he was 12 years old someone gave him a book called Explaining The Atom by Selig Hecht. The book showed Altman science's power to predict things. From then on he was a confirmed scientist. “I wasn’t interested in biology at the time. I liked nuclear physics,” he recalls today.

One Saturday afternoon, when Altman was still in high school, a friend asked, “Why don’t you come with me to McGill. I’m going to take the American SAT exams.” These Scholastic Aptitude Tests are a required part of any application to study at an American university. Altman had always thought he would stay in Canada and enrol at McGill for University in Montreal, but on a whim he wrote the SAT and he and his friend both applied to the Massachusetts Institute of Technology (MIT) near Boston. As it turned out, Altman got in but his friend did not.

Altman’s family had to scramble to get the money together to send him to this great school, and he wasn’t even sure he wanted to go. There was a big debate in the Altman household. But within three weeks at MIT Altman knew he wanted to stay; he was impressed by the high calibre of the students and he really enjoyed living away from home.

He received his bachelor of science (BSc) degree from MIT, then went to the University of Colorado Medical School in Boulder, where he obtained his doctorate (PhD) in Molecular Biology and met Leonard Lerman, a professor of molecular biology. Lerman was instrumental in helping Altman win a fellowship to work in Crick and Brenner’s lab in England where he began his Nobel prize-winning research. After those early discoveries, Altman came back to the USA and became a professor at Yale University. He never renounced his Canadian citizenship but now holds dual citizenship, both in Canada and in the United States.

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