Trudi Schüpbach and Eric Wieschaus: A shared passion for nature’s truth pg. 5
Two sets of eyes
Newly laid Drosophila eggs develop in about 10 days, first to larvae, then pupae, then flies. Somewhere in that cycle, certain genes tell each larva to segment into sections that eventually make up the adult fly’s head, tail, back and belly. But which of the fly’s 20,000 genes controls the process?
Wieschaus and Nüsslein-Volhard decided to look at nature in a different way, just as Dürer had done nearly three centuries earlier. First, they fed the flies toxic substances. This created random mutations that knocked out the function of individual genes. They bred the defective flies, then studied the genetic mutations by peering through a microscope.
For a scientist with an artistic eye, there was much to see. “We sat opposite each other at a dual eyepiece microscope,” Wieschaus recalls, smiling at the memory. “We were very competitive. We’d look and one of us would say ‘interesting’ and the other would say ‘not.’ I’d say ‘mutant.’ She’d say ‘not.’ It helped to have two good sets of eyes. There was a better chance of seeing.”
The pair culled through more than half of the 20,000 fly genes, and identified 15 genes in three groups that control embryonic segmentation. The first group of genes, called gap, causes the fly embryo to segment along the head-tail axis. The second group, pair-rule, governs every second segment in the embryo. The third group, segment polarity, refines the individual segments so that the head and tail look different. They published their results in the journal Nature in 1980.
“It took us two years to figure out how to do it and one year to do the experiments,” Wieschaus recalls. “We knew it was working, but we didn’t appreciate what we had done until it was over. We didn’t realize the importance until others reacted to it.”
Most scientists probably fantasize about receiving the phone call, the one from the Nobel committee, but Wieschaus declares he was not among them when he answered the phone in the fall of 1995.
“It was very early in the morning when I got the call, so I really had no feelings at all,” he explains, face deadpan, eyes teasing. “Then I woke up my three daughters, who were mostly interested in going back to sleep.”
“I was excited,” says Eleanor Wieschaus, who recalls the event with more clarity than her now-famous father. “Princeton is a small town and it was front-page news. I was in eighth grade -- the typical attention-seeking middle child. It was fun when the news came out.
“People were saying ‘Wow! Your dad won a Nobel Prize!’ My dad doesn’t come across as the typical scientist. He’s brilliant, but to me, he’s just my goofy dad.”
Schüpbach’s happiness over her husband’s achievement came with an additional perk -- it drew attention to their shared discipline of developmental biology. “I was very proud his work was deemed worthy of the award,” she says. “It was very important -- not just for Eric but for all the scientists who work in this field.”