The secrets of cell division: Dr. Sigal Ben-Yehuda


Dr. Ben-Yehuda (left) in her labWhat makes a close — but harmless — relative of the deadly anthrax produce spores asymmetrically when it is hungry and symmetrically when it is not? Dr. Sigal Ben-Yehuda of the Faculty of Medicine’s Department of Molecular Biology at the Institute of Medical Research of Israel-Canada (IMRIC) and her colleagues are seeking an answer as they try to elucidate how these dormant cells switch from one type to another with respect to differentiation and multiplication.

Using cell biology and molecular approaches, she and her team have developed new methods to study the structure and dynamics of DNA, RNA and proteins in these cells. Her research introduces novel concepts to spore biology and may help devise innovative ways to combat spore-forming pathogens.

The team uses bacillus subtilis, a bacterium found naturally in soil, as an experimental model to explore how asymmetry is generated. “This bacterium is a primitive but powerful tool that allows us to do a lot of genetic manipulation,” Ben-Yehuda explains.

“Every living organism goes through stages of asymmetrical cell division,” says Ben-Yehuda. “Otherwise, all our cells would be the same and we would never have differentiation. In embryos, almost all cell divisions are asymmetrical, leading to nerve, skin, liver, heart, brain cells, and so forth. But there is not always a difference in size between the split cells. In the case of bacillus subtilis, there is a striking visual difference that makes the asymmetrical differentiation easy to follow.”

In 2007, Dr. Ben-Yehuda was one of six young Hebrew University researchers who received five-year grants worth a total of $10 million from the European Research Council, a competitive European Union research funding body.