Scientists observe single gene activity in living cells

April 21, 2011

Researchers at Albert Einstein College of Medicine of Yeshiva University have for the first time observed the activity of a single gene in living cells. In an unprecedented study, published in the April 22 online edition of Science, Einstein scientists were able to follow, in real time, the process of gene transcription, which occurs when a gene converts its DNA information into molecules of messenger RNA (mRNA) that go on to make the protein coded by the gene.

Robert Singer, Ph.D., co-director of the Gruss Lipper Biophotonics Center at Einstein and professor and co-chair of anatomy and structural biology, is senior author of the paper. The study's lead author is Daniel Larson, Ph.D., previously a member of Dr. Singer's lab and now an investigator at the National Cancer Institute and head of the institute's Systems Biology of Gene Expression Section.

Using florescent proteins, the researchers were able to follow mRNA activity by inserting into a gene in live . RNA made from these sequences bound a modified ; expression of the entire gene resulted in mRNA molecules that were visible with fluorescent light. Gene transcription is a key step in synthesizing proteins, which govern the body's structure and function and underlie many diseases when present in mutated form or in aberrant amounts.

The study involved monitoring the activity of RNA polymerase—the enzyme that constructs mRNA molecules by linking single nucleotides together into a molecular chain. The researchers were able to directly observe and measure the key steps involved in transcription: initiation (triggered when proteins called bind to the promoter region of the gene), elongation (the progressive lengthening of mRNA as RNA polymerase adds more nucleotides to it) and termination (when mRNA breaks free from its DNA template, eventually migrating from the cell nucleus to the cytoplasm to serve as a blueprint for protein construction).

"The view of transcription in yeast that emerges from this study is that its initiation seems to be a random event that depends on the success of transcription factors searching through the yeast nucleus looking for a particular gene's promoter region," said Dr. Singer. "By contrast, once initiation occurs, recruits individual nucleotides for the growing mRNA molecule in an efficient and predictable manner."

"Understanding how gene expression is regulated in a single-celled organism such as yeast is a first step in understanding the same processes in humans, which have a vastly larger and more complex genome," said Dr. Larson. "But fundamentally, the same molecular laws governing transcription factors will still apply."

Explore further: Stability of mRNA/DNA and DNA/DNA duplexes modulates mRNA transcription

More information: The Science paper is entitled "Real time observation of transcription initiation and elongation on an endogenous gene."

Related Stories

Rewrite the textbooks: Transcription is bidirectional

January 25, 2009

Genes that contain instructions for making proteins make up less than 2% of the human genome. Yet, for unknown reasons, most of our genome is transcribed into RNA. The same is true for many other organisms that are easier ...

How RNA polymerase II gets the go-ahead for gene transcription

October 9, 2009

All cells perform certain basic functions. Each must selectively transcribe parts of the DNA that makes up its genome into RNAs that specify the structure of proteins. The set of proteins synthesized by a cell in turn determines ...

Recommended for you

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

4 million years at Africa's salad bar

August 3, 2015

As grasses grew more common in Africa, most major mammal groups tried grazing on them at times during the past 4 million years, but some of the animals went extinct or switched back to browsing on trees and shrubs, according ...

A look at living cells down to individual molecules

August 3, 2015

EPFL scientists have been able to produce footage of the evolution of living cells at a nanoscale resolution by combining atomic force microscopy and an a super resolution optical imaging system that follows molecules that ...

New lizard named after Sir David Attenborough

August 3, 2015

A research team led by Dr Martin Whiting from the Department of Biological Sciences recently discovered a beautifully coloured new species of flat lizard, which they have named Platysaurus attenboroughi, after Sir David Attenborough.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.