:: Posted by American Biotechnologist on 09-21-2011
Dr John J Rossi’s titles and accolades are many and varied — and well earned. In his current affiliation with the City of Hope Comprehensive Cancer Center, Rossi serves as chair and professor of molecular and cellular biology, dean of the graduate school of biological sciences, and associate director for laboratory research. He is co-leader of the cancer biology program and the first holder of the Lidow Family Research Chair. These professional accomplishments are complemented by numerous awards, including a 2002 Merit Award in the Division of AIDS, National Institute of Allergy and Infectious Diseases. The common thread that weaves all of these activities and achievements together continues to be an unabashed enthusiasm for and curiosity toward scientific discovery — specifically in the molecular genetics of disease.
Rossi received his doctoral degree in microbial genetics in the late 1970s. At the time, cloning was only just becoming a tool that researchers could use, and with Rossi’s exposure to this now basic technique, his fascination with genetics turned to the molecular aspects of the discipline. Rossi was drawn to postdoctoral studies in Dr Arthur Landy’s lab at Brown University because of Landy’s groundbreaking work in sequencing genetic information for the bacteriophage lambda. Landy’s work focused on trying to understand some of the sequences of the attachment site of the bacteriophage in its host chromosome. He also completed the first restriction map of any lambda phage. Rossi was particularly attracted by the technology he would have access to in this forward-thinking environment.
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:: Posted by American Biotechnologist on 12-17-2010
New genes that have evolved in species as little as one million years ago – a virtual blink in evolutionary history – can be just as essential for life as ancient genes, startling new research has discovered.
Evolutionary biologists have long proposed that the genes most important to life are ancient and conserved, handed down from species to species as the “bread and butter” of biology. New genes that arise as species split off from their ancestors were thought to serve less critical roles – the “vinegar” that adds flavor to the core genes.
But when nearly 200 new genes in the fruit fly species Drosophila melanogaster were individually silenced in laboratory experiments at the University of Chicago, more than 30 percent of the knockdowns were found to kill the fly. The study, published December 17 in Science, suggests that new genes are equally important for the successful development and survival of an organism as older genes.
“A new gene is as essential as any other gene; the importance of a gene is independent of its age,” said Manyuan Long, PhD, Professor of Ecology & Evolution and senior author of the paper. “New genes are no longer just vinegar, they are now equally likely to be butter and bread. We were shocked.”
The study used technology called RNA interference to permanently block the transcription of each targeted gene into its functional product from the beginning of a fly’s life. Of the 195 young genes tested, 59 were lethal (30 percent), causing the fly to die during its development. When the same method was applied to a sample of older genes, a statistically similar figure was found: 86 of 245 genes (35 percent) were lethal when silenced.
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