Credit: J. MCENTEE/SCRIPPS

William Ja, assistant professor of metabolism and ageing at the Scripps Research Institute in Jupiter, Florida, is getting noticed — and funded — for his cross-disciplinary research in protein chemistry and fruitfly genetics.

Did you intentionally leap from a PhD in chemistry into a postdoc in biology?

Yes and no. I majored in chemistry at the University of California, Berkeley, as an undergraduate, but always knew I wanted to do something biological. I just didn't know what. While getting my chemistry PhD at the California Institute of Technology in Pasadena, I wanted to bridge the gap between chemistry and biology, so I switched to a postdoc in pure biology. Then I got the chance to work with Seymour Benzer, a pioneer in molecular biology known for unravelling the ties between genes, behaviour and longevity. I loved it, but realized how difficult it is to stay at the forefront of two disciplines.

How did you come to work with Benzer?

My PhD focused on developing techniques to help peptides bind to protein targets. Benzer's work on the long-lived fruitfly mutant dubbed Methuselah was well known on campus. I wondered whether I could use my technique to develop peptides that could bind to Methuselah, to see whether they could affect ageing in flies. At the time, the Glenn Foundation for Medical Research in Carpinteria, California, had a scholarship programme that aimed to give PhD students a sabbatical-like experience. I applied, hoping to join Benzer's lab to do work on ageing in vivo. After that, Benzer invited me back as a postdoc.

What did you learn from that experience?

We found that certain peptides, when overexpressed, act as longevity drugs that can extend the lifespan of the fly. I found that I loved working on the organismal level. As a chemist, I had never worked with things that walk. I got interested in fly behaviour, courtship, memory and learning. And, because I had no biology experience, I asked naive questions — for example, I examined flies' eating and drinking habits.

Do you have a career strategy?

I enjoy working on questions that are fun and interesting and that no one else is exploring. One example is measuring how much flies eat, which is difficult in such a small organism. Another is whether fruitflies get thirsty, which questions a 100-year tradition of rearing them in the lab without free water. We found that diet and thirst can affect a variety of fruitfly phenotypes. My papers are often the result of ideas thrown out at lunch or over drinks — I've had a 10–20% success rate following up on questions conceived in a bar. That is how two of my best papers — the questions I mention above — began.

How were the diet and thirst findings received?

Some people doing fruitfly research get upset when I present my results, because my findings might cast doubt on their own work. In those instances, I've encouraged authors to test whether thirst makes a difference and publish their results — that is the only way that we'll know if this is a significant problem. Debates are part of science, but I would say that the politics of science has been the biggest surprise to me as I've moved into a more independent stage of my career. I didn't realize, as a postgraduate student, how shielded I was from politics. I've learned that being a good scientist doesn't mean you are always right.

As a new assistant professor in a bleak economy, where are you looking for money?

There is a lot of stress in this economy about getting grant money, but I do science best when I'm working on diverse projects. The Glenn Foundation surprised me with an unsolicited US$60,000 award last November to continue my research into ageing. And in October, I received funding to explore non-surgical sterilization methods for dogs and cats from the Found Animals Foundation in Los Angeles, California, a non-profit organization dedicated to minimizing euthanasia at animal shelters. It had a prize for creating a single-dose sterilant for cats and dogs, and I wondered about using a cytotoxin to attack cells important for reproduction. I wrote a proposal capitalizing on my protein-chemistry and molecular-biology experience and asked for $200,000. They agreed.