LSTM researchers among first to sequence snake genome

December 03, 2013

Researchers from LSTM, along with a team of international biologists who have recently sequenced the genome of the king cobra, say that their work reveals dynamic evolution and adaptation in the snake venom system, which seemingly occurs in response to an evolutionary arms race between venomous snakes and their prey.

A paper co-lead by Dr Nicholas Casewell, a NERC research Fellow at LSTM, and 34 co-authors from six countries, including the Director of the Alistair Reid Venom Unit at LSTM, Dr Robert Harrison, has been published in the Proceedings of the National Academy of Sciences (PNAS). Members of this team also analysed the genome of the Burmese python (Python molurus bivittatus) and used it for comparison with the king cobra (Ophiophagus Hannah). These papers represent the first complete and annotated snake genomes.

Snake venoms are complex protein mixtures encoded by several gene families and these proteins function synergistically to cause rapid paralysis or death in prey. The study provides an insight into the biology of the venom in snakes, and allows the understanding of the evolution of venom genes at the genome structural level. Armed with the both the king cobra and Burmese python genome the team was able to show that, despite previous hypotheses that venom genes evolve "early" in the lineage leading to snakes, venom gene families do not duplicate early, in fact the study shows that the rapid and extensive expansion of functionally important venom toxin families is restricted to the venomous "advanced" snake lineage. The diversification of these toxins correlates directly with their functional importance in prey capture, for example the most pathogenic king cobra toxin family have undergone massive expansion, while, in contrast, venom proteins with less important functions do not participate in the evolutionary arms race occurring between snakes and their prey.

Dr Nicholas Casewell said: "These are the first snake genomes to be sequenced and fully annotated and our results in relation to the king cobra provide a unique view of the origin and evolution of snake venom, including revealing multiple genome-level adaptive responses to natural selection in this complex biological weapon system. These adaptations include the massive and rapid expansion of gene families that produce venom toxins, providing the snake with a highly toxic protein mixture required to overcome a variety of different prey and also circumvent any resistance to venom that may have developed in such prey. Our study provides unique genome-wide perspectives on the adaptive evolution of venom systems as well as protein evolution in general. As such it contributes an essential foundation for understanding and comparing evolutionary genomic processes in venomous organisms."

The work carried out by Dr Casewell and his co-authors was used in the second paper outlining the analysis of the genome of the Burmese python, also published in the same edition of PNAS.
-end-
You can read the article here.

For further information, please contact:

Mrs Clare Bebb
Senior Media Officer
Liverpool School of Tropical Medicine
Office: +44 (0)151 705 3135
Mobile: +44 (0)7889535222
Email: c.bebb@liv.ac.uk

Liverpool School of Tropical Medicine (LSTM) has been engaged in the fight against infectious, debilitating and disabling diseases since 1898 and continues that tradition today with a research portfolio in excess of well over £200 million and a teaching programme attracting students from over 65 countries.

For further information, please visit: http://www.lstmliverpool.ac.uk

Liverpool School of Tropical Medicine

Related Evolution Articles from Brightsurf:

Seeing evolution happening before your eyes
Researchers from the European Molecular Biology Laboratory in Heidelberg established an automated pipeline to create mutations in genomic enhancers that let them watch evolution unfold before their eyes.

A timeline on the evolution of reptiles
A statistical analysis of that vast database is helping scientists better understand the evolution of these cold-blooded vertebrates by contradicting a widely held theory that major transitions in evolution always happened in big, quick (geologically speaking) bursts, triggered by major environmental shifts.

Looking at evolution's genealogy from home
Evolution leaves its traces in particular in genomes. A team headed by Dr.

How boundaries become bridges in evolution
The mechanisms that make organisms locally fit and those responsible for change are distinct and occur sequentially in evolution.

Genome evolution goes digital
Dr. Alan Herbert from InsideOutBio describes ground-breaking research in a paper published online by Royal Society Open Science.

Paleontology: Experiments in evolution
A new find from Patagonia sheds light on the evolution of large predatory dinosaurs.

A window into evolution
The C4 cycle supercharges photosynthesis and evolved independently more than 62 times.

Is evolution predictable?
An international team of scientists working with Heliconius butterflies at the Smithsonian Tropical Research Institute (STRI) in Panama was faced with a mystery: how do pairs of unrelated butterflies from Peru to Costa Rica evolve nearly the same wing-color patterns over and over again?

Predicting evolution
A new method of 're-barcoding' DNA allows scientists to track rapid evolution in yeast.

Insect evolution: Insect evolution
Scientists at Ludwig-Maximilians-Universitaet (LMU) in Munich have shown that the incidence of midge and fly larvae in amber is far higher than previously thought.

Read More: Evolution News and Evolution Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.