The Cavanilles Institute on Biodiversity and Evolutionary Biology, part of Valencia University,
The Cavanilles Institute tackles evolution from a variety of perspectives; one of them is to elucidate evolution's molecular mechanisms--the remit of the evolutionary genetics group, led by Andrés Moya.
Diversity is a key word in evolution, and it also has a place in describing those who study it, at least at the Cavanilles Institute and in Moya’s evolutionary genetics group. The factors that drew 3 of Moya’s 15 Ph.D. students--Iñaki Comas, Vicente Pérez, and Vicente Sentandreu--and one of his 4 postdocs--Rosario Gil--to evolutionary biology in the first place have little in common. This diversity of perspectives benefits the research.
All 3 Ph.D. students--Comas, Pérez, and Sentandreu-–got a B.Sc. in biology from the University of Valencia and did their final-year research project at the Cavanilles Institute. But this is about all they have in common; they all entered evolution for different reasons. Comas, who is now in the third and penultimate year of his Ph.D., says that he knew as early as in the second year of his university degree that he wanted to work in evolutionary biology. "One of the subjects was an introduction to the theory of evolution, and I liked it very much," says Comas. So for his final-year research project he went to the Institute to study population genetics--in particular, how parameters such as population and genome size may affect the evolution of populations--using computer models. He stayed on for a Ph.D., specialising in bioinformatics and the design of computer tools for the study of evolutionary genomics.
For Pérez and Sentandreu, both of them now in the final year of their Ph.D., it was more a matter of finding, in evolution, a niche that fitted their other interests well. For Pérez that niche was genetics. "At the beginning, I hadn’t decided whether I wanted to work specifically in evolutionary genetics or in a different field of genetics," says Pérez. But that was before he found an interesting final-year project in genetics at the Institute, which led directly into a Ph.D. project. "Initially, [my project] was pretty technical. I was sequencing genomes independently; it wasn’t very evolutionary," he says. But after 3 years of sequencing, the time came to compare genomes and analyse similarities in an evolutionary light. Pérez found this work very interesting, he says. "The more I got into this Ph.D., the more I liked it."
Sentandreu, on the other hand, "was mainly interested in biochemistry," although he was also keen to work in human health. He too found a final-year research project --which, as with Pérez, led directly into a Ph.D. project--in the Cavanilles Institute. He studied the evolution of HIV and Hepatitis C viruses in humans, and the interaction between the fields of evolution and health is what interested him, he says.
Gil--the postdoc--brings a broad background to the study of evolutionary genetics. "I have been moving to different fields during my scientific career," she says. After working on the genetics of yeasts during a Ph.D. in pharmacy at the University of Valencia, Gil moved to the United States for a postdoc on human suppressor genes. When she returned to Spain 3 years later, she found the local field of human genetics too competitive to break into, so she started studying beer-making at a brewing company. When that lab closed she went back to university, working in a biochemistry and molecular biology lab to study gene expression during wine making, but this contract, too, came to an end. "I contacted this group because they were looking for a postdoc. I didn’t know much about [evolution] but I had lots of experience with different techniques" in molecular biology, she says. She got the job 5 years ago and started working on the evolution of bacterial genomes. She worked hard to catch up with the field of evolution, and got a Ramón y Cajal contract 2 years ago. "I finally feel [that] I am an expert and [that] I have a field," she says.
Diverse Research Projects
Gil is now sequencing and comparing the genomes of bacteria that live within insects in a mutually beneficial relationship, the so-called endosymbionts. Because their hosts provide a stable and rich environment, endosymbiotic bacteria have seen some of their genes become redundant, so they shed them over time. Currently "There are seven different genomes of endosymbionts sequenced, and comparing them we can learn what has been happening"--what genes were lost when, and how--says Gil. It's like a puzzle, she says, "assembling sequences and putting things together so that it makes sense." Her work could one day help to determine the minimum genome for life, she says. Pérez, who has Gil as one of his two supervisors, has also been involved in this project, sequencing and analysing the smallest bacterial genome known so far.
Comas, too, is working on the evolution of bacterial genomes, but from a different perspective. One of the outputs of the evolutionary analysis of genomes is the reconstruction of phylogenetic trees that map out common ancestors, their descendants, and the relationships between the different species. But "whether there is a species tree for bacteria is one of the biggest questions in evolution," says Comas. Traditional phylogenetic methods assume that genes may only be transferred from parents to offspring, but bacteria have the unusual ability to exchange genes among peers. So Comas is trying to shed light on "the general rules of microbial genome evolution applying bioinformatics approaches," and "to develop tools for the evolutionary genomic analysis of bacteria," he says.
Sentandreu’s work is of a still-different kind. Sentandreu is looking at the evolution of HIV and Hepatitis C viruses in co-infected patients. "One [virus] can modulate the evolution of the other," he explains. To shed light on how co-infection may affect evolution, Sentandreu sequences parts of the genome of both viruses and analyses genetic variability and adaptive evolution in co-infected patients. "The evolutionary analysis of these data is very interesting," he says. In the long-term he hopes it will help understand how the viruses evolve while passing from patient to patient, or how they develop resistance against treatment.
A Common View
However different these projects may be, they all have a common element. They all use bioinformatics tools and computer simulations to analyse the genomic data in an evolutionary light. "In evolutionary biology, almost everybody has to make a phylogenetic tree at one point in his or her work," says Comas.
Whether they came to work in evolution for their particular interest in the field or the opportunities it offered them, all four young scientists view evolution as a cornerstone of scientific research. "As [the evolutionary biologist] Theodosius Dobzhansky said, ‘Nothing in biology makes sense except in the light of evolution,’ " says Gil. "Everything that is around us is due to evolution, so we can’t escape it." The relevance of evolution to many different fields is particularly obvious in the Cavanilles Institute. "In this centre, we are [all] focused on evolution from different points of view, not only from genetics but [also] ecology, palaeotonlogy, biodiversity, and conservation," says Pérez.
The Importance of Diversity in Evolutionary Careers
All 4 researchers feel that to make it in evolutionary genetics, skills in bioinformatics and mathematics are key. But in Spain, the universities that offer training in bioinformatics are few. So young researchers often have to learn these skills on the job, which makes choosing the right environment even more important. "We have to ask for help to the other people in our lab for a specific problem," says Pérez.
Moya, the group leader, agrees about the importance of bioinformatics. "We are trying to prepare our students with enough computational skills in biology, mostly bioinformatics applied to evolutionary issues … through the subjects of our Ph.D. programmes," he says in an e-mail. These skills are important if they want to stay in academia, he says, but may also allow them to go into more applied projects if they choose to. "We are working, in some way, in applied evolutionary biology, from genomics of human pathogens, molecular epidemiology of infectious diseases, forensic DNA, or conservation genetics. These are emergent areas … and positions are opening for young people to work in these areas."
The diversity of backgrounds that can be found in his lab is something that Moya especially values. "[Within my own group] we focus on a scientific problem putting together the expertise of the different scientists," he says. "This way we cross barriers--something [that is] very difficult--and the students benefit from a different way of doing science, from a broader perspective."
Elisabeth Pain is contributing editor for South and West Europe.