Nav: Home

Directed gene-copy variation: The key to conquering new environments

June 27, 2017

A study of yeast reveals new mechanism that allows cells to adapt to environmental changes more rapidly by accelerating genetic changes around genes that boost fitness, publishing 27 June in the open access journal PLOS Biology, by Dr. Jon Houseley and colleagues at the Babraham Institute in Cambridge, UK.

Species evolve over time because individuals that are most suited to their environment survive and have more offspring -- what is known as the 'survival of the fittest'. However, it's typically assumed that those differences in fitness result from genetic changes that occur randomly; the new study uncovers a mechanism by which changes can be specifically targeted at genes that are being more heavily used.

The researchers used yeast to examine changes to the number of gene copies in each cell. Although we think of cells as containing one or two copies of each gene at most, they often carry more copies of many genes; increasing the number of copies allows cells to synthesise more protein product from those genes, which make processes more efficient. Houseley and colleagues' results show that when a cell makes intensive use of a particular gene (by transcribing it into mRNA to make protein), it has a greater chance of undergoing a change in copy number. In some cells this results in more copies, helping them to become more suited to their environment. In other words, the more heavily a gene is used, the more likely it is to change its copy number and potentially make the cell fitter.

In particular, the study focused on a gene in yeast called CUP1, which is needed for cells to survive in environments with high levels of copper. Yeast cells typically carry between two and fifteen copies of this gene, but when levels of copper rose, the researchers observed that variation in copy number increased. As a result, some cells gained additional copies of the CUP1 gene, which allowed them to outcompete cells with fewer CUP1 copies in the same environment. Further results demonstrated that cells can control this process via a protein called Rtt109, which adds chemical modifications to particular sites in the genome, promoting copy number change in those areas.

Ryan Hull, the PhD student leading the study in the Houseley lab, said: "We think of genetic change as a purely random process, but it makes sense for cells to develop a way to focus this process to help them adapt to changing environments. There are already specific examples of this, but what's interesting here is that the mechanism we've proposed potentially works for many genes across the genome."

Future work in this area will aim to determine how many genes in the genome can make use of this process to adapt their copy number to environmental changes and to examine whether similar systems may operate to drive evolution in other organisms.
-end-
In your coverage please use this URL to provide access to the freely available article in PLOS Biology: https://doi.org/10.1371/journal.pbio.2001333

Citation: Hull RM, Cruz C, Jack CV, Houseley J (2017) Environmental change drives accelerated adaptation through stimulated copy number variation. PLoS Biol 15(6): e2001333. https://doi.org/10.1371/journal.pbio.2001333

Funding: MRC http://www.mrc.ac.uk (grant number). Doctoral Training Partnership funding for PhD students, received by RMH and CVJ. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The Wellcome Trust wellcome.ac.uk (grant number 088335, 110216). Received by JH. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. BBSRC http://www.bbsrc.ac.uk (grant number). Babraham Institute Epigenetics Strategic Programme Grant. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: in addition to the funding described in the Financial Disclosure, JH declares that part of this work (although not the presented data), specifically the potential of histone acetyltransferase inhibition to prevent adaptation, forms part of a patent application.

PLOS

Related Genes Articles:

Are male genes from Mars, female genes from Venus?
In a new paper in the PERSPECTIVES section of the journal Science, Melissa Wilson reviews current research into patterns of sex differences in gene expression across the genome, and highlights sampling biases in the human populations included in such studies.
New alcohol genes uncovered
Do you have what is known as problematic alcohol use?
How status sticks to genes
Life at the bottom of the social ladder may have long-term health effects that even upward mobility can't undo, according to new research in monkeys.
Symphony of genes
One of the most exciting discoveries in genome research was that the last common ancestor of all multicellular animals already possessed an extremely complex genome.
New genes out of nothing
One key question in evolutionary biology is how novel genes arise and develop.
Good genes
A team of scientists from NAU, Arizona State University, the University of Groningen in the Netherlands, the Center for Coastal Studies in Massachusetts and nine other institutions worldwide to study potential cancer suppression mechanisms in cetaceans, the mammalian group that includes whales, dolphins and porpoises.
How lifestyle affects our genes
In the past decade, knowledge of how lifestyle affects our genes, a research field called epigenetics, has grown exponentially.
Genes that regulate how much we dream
Sleep is known to allow animals to re-energize themselves and consolidate memories.
The genes are not to blame
Individualized dietary recommendations based on genetic information are currently a popular trend.
Timing is everything, to our genes
Salk scientists discover critical gene activity follows a biological clock, affecting diseases of the brain and body.
More Genes News and Genes Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Warped Reality
False information on the internet makes it harder and harder to know what's true, and the consequences have been devastating. This hour, TED speakers explore ideas around technology and deception. Guests include law professor Danielle Citron, journalist Andrew Marantz, and computer scientist Joy Buolamwini.
Now Playing: Science for the People

#576 Science Communication in Creative Places
When you think of science communication, you might think of TED talks or museum talks or video talks, or... people giving lectures. It's a lot of people talking. But there's more to sci comm than that. This week host Bethany Brookshire talks to three people who have looked at science communication in places you might not expect it. We'll speak with Mauna Dasari, a graduate student at Notre Dame, about making mammals into a March Madness match. We'll talk with Sarah Garner, director of the Pathologists Assistant Program at Tulane University School of Medicine, who takes pathology instruction out of...
Now Playing: Radiolab

What If?
There's plenty of speculation about what Donald Trump might do in the wake of the election. Would he dispute the results if he loses? Would he simply refuse to leave office, or even try to use the military to maintain control? Last summer, Rosa Brooks got together a team of experts and political operatives from both sides of the aisle to ask a slightly different question. Rather than arguing about whether he'd do those things, they dug into what exactly would happen if he did. Part war game part choose your own adventure, Rosa's Transition Integrity Project doesn't give us any predictions, and it isn't a referendum on Trump. Instead, it's a deeply illuminating stress test on our laws, our institutions, and on the commitment to democracy written into the constitution. This episode was reported by Bethel Habte, with help from Tracie Hunte, and produced by Bethel Habte. Jeremy Bloom provided original music. Support Radiolab by becoming a member today at Radiolab.org/donate.     You can read The Transition Integrity Project's report here.