all Pamela A. Silver stories

Scientists synthesize memory in yeast cells

404132862 — Sun, 16 Sep 2007 15:03:55 -0400

Harvard Medical School (HMS) researchers have successfully synthesized a DNA-based memory loop in yeast cells, an experiment that marks a significant step forward in the emerging field of synthetic biology.

After constructing genes from random bits of DNA, researchers in the lab of Pamela Silver, a faculty member in Harvard Medical School’s Department of Systems Biology, not only reconstructed the dynamics of memory, but also created a mathematical model that predicted how such a memory “device” might work.

Proteasome recognized as nuclear player on gene-transcription team

70652986 — Mon, 26 Mar 2007 06:26:37 -0400

One of the most common agents in the cytoplasm of the cell, the proteasome, also plays a widespread and critical role in transcription from inside the cell nucleus.

Pam Silver, Kathryn Auld, and their colleagues report in the March 17, 2006 Molecular Cell that the proteasome binds and critically regulates the transcription of some of the most highly expressed and important genes in the yeast genome, including those involved in lipid metabolism, mating behavior, and the making of ribosomal proteins.

"We found the proteasome to be very important in so many roles in yeast transcription that I cannot imagine it is not important in other organisms," Auld said.

Idea inspires new screening test for anti-cancer agents

70652986 — Mon, 26 Mar 2007 05:34:15 -0400

In a study published in the December 2003 issue of Cell, investigators from Dana-Farber Cancer Institute demonstrated that a new technique has helped them to identify a class of existing drugs able to kill certain types of cancer cells. "This is an example where one person's work – that of Bill Sellers [of Medical Oncology] – triggers an idea by someone in another lab that leads to a new approach," says Pamela Silver, of Cancer Biology, the study's senior author. "In this case, it has led to a type of screening test with broad potential." When Tweeny Kau, a member of Silver's lab, learned about Sellers' findings, a realization dawned. The result was a "cell-based chemical genetic screening test" for potential cancer drugs. Using high-speed automated equipment, researchers screened more than 18,000 compounds in cancer cells where the P13 pathway was abnormal. They discovered a number of compounds with anti-cancer properties, including an existing class of drugs known as phenothiazines, which are used to treat certain psychotic conditions. Another of the successful compounds is the natural product of a sea sponge, and some are similar to substances known to block certain key enzymes in the cell.