By Aida Maric, PhD, Plant Physiology Assistant Features Editor
Jurriaan Ton is Professor of Plant Environmental Signalling at the University of Sheffield in UK. He obtained his PhD at the Utrecht University in the Netherlands, where he studied plant-microbiome interaction in the lab of Prof. Corné Pieterse. After extensive international experience and after working as post-doc in Switzerland and as a PI in Utrecht University and Rothamsted Research, he became a professor at the University of Sheffield in 2015. His current research is focused on understanding the (epi)genetic basis of stress memory; as well as chemical interactions between plants and microbes.
This interview had the most scenic Zoom meeting background ever as Jurriaan was working from home in southern France. We reached consensus on the recommended soundtrack to listen to while reading this interview: “Anything” by Pink Floyd. Enjoy!
Aida: Since we want people to know the person behind the editor’s name, let’s start from the very beginning. How and why did you get into plant science?
Jurriaan: That was a bit of a detour, to be honest. I always wanted to become a biologist from very early on, but I had never really envisaged I would become a plant biologist. So, when I was growing up and doing the Dutch equivalent of A levels, I had very naive expectations of becoming a biologist: I wanted to study dolphins and go on all sorts of adventurous field trips. And then I started my degree in the early 1990s at Utrecht University in the Netherlands. In one of the first weeks, we had a zoology practical where we had to cut open a rat. I was really horrified and disappointed in myself because I wasn’t coping well with the bloody mess I made of it. That was about three or four weeks into my degree. Then I figured that at least zoology was not what I wanted to specialize in. I was lucky that the first year curriculum in Utrecht started off very broad, so it gave me a perfect opportunity to sample lots of different biological disciplines.
And already in my first year of study I became captivated by plant biology. This was during my plant biology course, which involved lectures by Hans Lambers and Aart van Bel, two incredibly successful and charismatic plant biologists. They really sparked my interest in plants and made me realize how wonderfully versatile plants are in adapting to their environment. I progressed through my undergraduate courses and realized in 1993 that there was an opportunity for me to go to Italy as an Erasmus student. The problem was that only one biology department was actively recruiting students for Erasmus exchange projects: the paleobiology department. So, I decided to learn more about paleobiology for a while, which allowed me to do an Erasmus project in Italy. I spent about half a year in Italy, which was fantastic. I didn’t learn much Italian but, ironically, I did learn to speak English because I was hanging out with a lot of English and Irish exchange students. And because of my poor linguistic abilities, my tutor in Firenze [Florence] sent me to a fieldwork station in the middle of the Apennines that was run by someone who had done his PhD in the lab of Walter Alveraz at Berkeley (so he was fluent in English). Because I had climbing equipment, this guy benefited from my equipment to sample sediments from steep outcrops to study nannofossils.
I absolutely loved it. But after that year I realized that paleobiology is a mostly one-way traffic in terms of information, isn’t it? You sort of observe things that happened millions and millions and millions of years ago, and then you try to reconstruct what happened. I was studying mass extinctions, which was wonderfully exciting, but what I missed was the ability to experimentally manipulate the system. Then I came back to Utrecht and proceeded with my masters. I figured that I wanted to specialize in something where you have the freedom to go into the lab in the morning, do an experiment, and interpret the results the same or following day. I then remembered how much I had enjoyed plant biology in my first and second year. Of course, there are no ethical objections to torturing plants at all. So, you can do whatever you want with plants; they’re a perfect experimental object. And I particularly liked the plant-environmental interactions aspect in plant biology because it involves so many other biological disciplines. Apart from plant biology, it includes elements of molecular biology, biochemistry, genetics, microbiology, ecology/evolution, and even a little bit of zoology in the form of herbivores and entomology. It really sits on the crossroads of different biological disciplines. So, I realized that this is where I want to be, because it combines nearly all aspects of biology.
A: That´s a very exciting journey. We will come back to your actual scientific work a bit later. I saw online that you have a lot of roles. You are a group leader, a professor, editor for Plant Physiology, and who knows how many other things you’re doing that are not on the official website. I guess it can be overwhelming sometimes. How do you balance work and your private life?
J: This meeting is recorded, I shouldn’t go on a rant about the state of higher education in the UK, but I will anyway. I don’t regret having gone to the UK back in 2007 to continue my career. The UK has a very good plant biology community that is very supportive of each other. The problem is that higher education in the UK has been privatized to an extent that it affects its sustainability in terms of quality of teaching and research. This process not only resulted in ridiculous tuition fees for students (which can infringe on the quality of teaching because students expect to have a degree because they pay £9.25K a year in tuition fees), but it also affects research quality and wellbeing of staff. The people leading UK universities are more or less more forced to only consider financial spreadsheets and don’t have the time or opportunity to consider long-term strategy and vision. And that’s very sad. It also means that academics have had to take on so many additional roles than teaching and research over the years. In the past, you had much more support from skilled administrative staff, who helped you out with financial costs of grants and all that sort of stuff. That has been cut back. Of course, there is some replacement in the form of electronic financial tools and other gadgets. While that’s all great, it still means that you need to do the financial accounting yourself, whereas you used to have admin staff doing it for you. Another example of functions that have been cut back are skilled lab managers. Lab managers, or technicians, are so important in the wider academic ecosystem and are particularly critical for research in experimental biology. For instance, you have a brilliant student or postdoc, but they leave after three or four years. Lab managers and technicians used to be core-funded, so they offered continuity and stability in your lab, which is incredibly important for the continuity and progression of your research group. To be honest, I try to spend time in the lab as much as I can, but the unfortunate reality is that I spend most of my time in my office doing administrative work. If I need to switch on a mass spectrometer, I struggle to know how to do that! So, at one point, you find yourself in a situation where you need to be administrator, a student counselor, an expert in health and safety, a social media outreach/impact champion, and a charismatic motivator and coach for your postdocs and students. On top of all that, you still need to have good research ideas, be an excellent writer, and keep track of the literature and latest development in the field. So, yeah, it becomes a bit much sometimes, and it’s not surprising that a lot of people in academia move to industry to find a better work-life balance. For me personally, the choice is to stay in academia though. I’m 50 years old now and I’ve made my decision, but I do sometimes wonder whether the UK is the best place, particularly when I compare my work-life balance to that of my academic colleagues in mainland Europe. Higher education in the UK and the USA have a similar funding model, which is based on growth and competition. This is simply not sustainable, nor is it appropriate for an institution that drives future innovation in our society. Governments need to change the funding model and acknowledge the fact that higher education is more than just a financial export product.
A: Looking back at what you said about the privatization of academia, where do you see the future of scientific publishing?
J: That’s a very good question. The publishing business is also highly privatised with a clear objective of financial gain. This is causing tension because our funders want to have as much impact as possible from the funds they grant us. They encourage (or actually expect) us to publish open access, which becomes very expensive. If you want to publish in a decent journal, you sometimes end up with publication charges of over £3.5-4K, leading to a situation where universities are no longer capable of paying the publication fees. So. you get this surreal situation where you get your paper published in a really good journal but you cannot afford the open access charges. And more so than often, the grant that funded that research expired one or two years ago, so these funds are no longer available. Now, there are creative solutions. For instance, the three research-led universities in Yorkshire teamed up to share an open access repository for manuscripts that are being published in their original format (i.e. not laid out in journal format). So, there are ways around it, but it remains complicated and sometimes difficult to navigate.
A: That’s the thing, it’s not a structural solution. Despite the difficulties, what do you like about being an editor for a journal?
J: I love that job. Being a monitoring editor for Plant Physiology is a very rewarding job. I’ve been doing it for about eight years now and although it sometimes gives quite a bit of extra work, it always is very fulfilling. First, it forces me to stay up to date with the field. As a monitoring editor, you need to read the papers, firstly to decide whether it is worth sending them out to reviewers and secondly when the review reports come in and you need to render a decision. But because you have the review reports at the end of the process, they quickly help you grasp the main message of the paper. Also, when you receive a manuscript and go through it, you start thinking, “Okay, so who could I invite as a peer reviewer?” So you start mining your network and searching around who could do it, during which you get to know a lot of interesting people. And that is in addition to all the exciting science that you learn from reading these manuscripts that pass your desk. Plant Physiology is a wonderful journal. It might not be the highest impact journal, but it’s a highly respected and influential journal that has operated in the top-ranks of plant biology journals over multiple decades. It’s not one of these journals that goes up an impact factor and then collapses after a while, but it is a consistent journal with a wide-ranging readership that continues to innovate itself. This in my view is a trademark of quality that is also reflected by the papers that we receive – across the board, we tend to get good-quality manuscripts describing interesting discoveries. And of course, the section editors do a great job to filter out the manuscripts that are less appropriate, as well.
A: What are you looking for in a paper? What makes you say, “OK, this is something I will send for review,” or “this is something that gets rejected right away”?
J: Plant Physiology is a journal that publishes research results about mechanisms in plants. This can be anything from the molecular level to the ecological level. For instance, chemical ecology, which studies environmental interactions via chemical signals, is something that is of increasing interest to Plant Physiology. But I guess the most important thing for Plant Physiology is that there is a strong element of validation and causal evidence, which goes beyond just a description of omics results. Because we are in the era of “-omics biology,” everybody who holds a grant or has a financial budget can work out how to do transcriptomics/metabolomics analysis. Accordingly, there is a risk that you end up with papers that only present piles of omics data without providing conclusive evidence about the underpinning mechanism. In my view, good papers can include “-omics” results, but these data should be used as a starting point for more hypothesis-led research. In other words, your paper needs to have a validation step to establish causality, to separate cause from effects. I think that is really important for Plant Physiology. And, of course, the other thing that is important is to have a title, abstract and figures that are appealing, original and intuitive; they need “tickle your curiosity.” And if it does, it’s certainly more likely that your paper gets through that first hurdle of the editorial sift.
A: Talking about papers, your lab is interested in plant memory and memory of defence, and it’s a field that has been growing a lot recently with a lot of exciting questions, as reviewed by you and your colleagues. You were in the front row there, I guess. How do you see the future of this field and is there one big question that you would like to answer in terms of plant memory?
J: Yeah, absolutely. This is something that goes back to that decision I made in the early 1990s, when I wanted to learn more about plants as a central regulators of ecological interactions. One thing that has always surprised me is how plants manage to survive in their environment. Plants don’t have a central nervous system – OK, there’s a bit of electrical signaling, but it’s not even close to the complexity that you find in the central nervous system of animals. They also don’t have a cellular immune system, yet they sit at the bottom of the food chain and cannot escape from their (often very stressful) environment. So how do they manage and adapt so quickly and efficiently to all these different stressors, be it biotic and abiotic? That has been a question that has been captivating me for quite a while.
In terms of plant defense, the vast majority of the field focuses on innate responses: there is an alarm signal from the environment and the plant, like a reflex, responds to that. This is a very important first line of defense – I’m certainly not disputing that – but there must additional mechanisms for plants to be able to survive in their environment. In order to be so versatile in adapting to a constantly changing environment, plants need to be capable of acquiring some form of stress memory (i.e., to “learn” from their environment). In my experience, they can do that in two ways. First, they use internal pathways to acquire stress memory, which is largely encoded in the plant’s epigenome. In our lab, we call this the “internal hard drive” of stress memory. At present, our lab is mostly studying DNA methylation at transposable elements (TEs). This mechanism primarily serves to silence the activity of TEs, but stress-related changes in TE methylation seem to play an important secondary role in plant stress memory. This could perhaps explain why so many plants have huge genomes that largely consist of TE-derived sequences – they use it as an epigenetic hard drive of stress memory. And then there is the “external hard drive” of stress memory: when plants are exposed to biotic stress (e.g., herbivores and diseases), they emit semiochemicals that recruit other organisms to fight off the attacker. The classic example comes from pioneering work that was done decades ago by Marcel Dicke and Ted Turlings, who discovered that herbivore-infested plants emit volatiles that recruit natural enemies of the herbivore. When I was a postdoc in Ted’s lab in the early 2000s, I investigated the possibility that some of these volatiles prime defenses in neighboring plants, hence activate the internal hard drive of stress memory. We now know that these tri-trophic interactions can operate below ground in response to disease: when plants are attacked by pathogens, they change their root exudation chemistry to select/recruit a different rhizosphere microbiome with disease-suppressive activity. This altered microbiome can have long-lasting effects on the plant as it functions as a self-perpetuating entity: once it’s there, it’s very difficult to get rid of. In fact, it can even benefit plants of the next generation, provided the offspring germinates close to the parental plant. So, this external hard drive is a beautiful example of long-term stress memory that can even be passed on to the next generation. I’m very much interested in identifying the underpinning mechanisms and signals of these two forms of stress memory, how they interact with each other, and how they benefit the plant.
A: It’s a very exciting topic. When you talk about microbiome, I’ve seen talks, but I’m always puzzled about how you do an experiment on the microbiome of the soil. What are the microorganisms that you add?
J: This is a very good question. I guess this is the reason why my lab has focused more on the “internal hard drive,” because it’s easier to study. Amplicon sequencing has been around for more than a decade now, and we know how to obtain a reasonably comprehensive fingerprint of the microbial community in soil. But to take this information to the next step, and link it to functionality, remains challenging. Once you have profiled the microbiome, you have a snapshot of the community structure, particularly in bulk soil that is not stabilized by the chemical and physical influence of the host plant. However, it can take several minutes (e.g., a rain shower) to profoundly change the composition of soil microbiome. This, in my view, diminishes the functional information you can obtain from microbial soil profiles. How informative are they really for the effects that they can have on plants? On top of that, amplicon sequencing is very good in getting an impression of “who” is there, but we don’t know “what” they do. What we do know is that if you have a bacterial culture in vitro and you feed it root exudation chemicals, you see all sorts of weird and wonderful responses. So the same bacteria respond to signals from the plant, and that’s something you won’t capture in a bulk standard community profiling by amplicon sequencing. Frankly, I have the feeling that there’s a bit of hype going on about microbiomes in our field and this is perhaps why my lab has avoided this line of research recently. It is perhaps comparable to the hype of the DNA microarrays 25 years ago; everybody started doing transcriptomics, but then we realized that there is a limit to the information we can extract from these data. I think this is similar for soil microbial profiling. We need to value the information we can get out of these data, but also consider its limitations before jumping to conclusions.
A: Very good, we’ll move away from pure science now. So you mentioned that you’ve been to different countries. You moved to the UK some years ago now. Do you think that this international experience helped you in a way, or is it necessary, really, to move around so much as we do today? What did this international experience give you that you otherwise wouldn’t have?
J: Again, they’re a really good question. If you would have asked me 20 years ago, I would have enthusiastically said: “Oh, it’s very important to experience working in different countries.” To some extent, for me personally, I still believe it was the right decision for me to work in Switzerland, both in the molecular plant pathology lab of Brigitte Mauchg-Mani, the chemical ecology lab of Ted Turlings, and in Utrecht as PhD student and research fellow in what turned out to be a world-leading lab in MPMI research; Corné Pieterse is one of the leaders in the field and I was very privileged that he was my PhD supervisor. I was also very lucky to work as a research fellow in the agricultural research institute Rothamsted Research and consider the translational aspects of plant biology—how can all this fundamental research on plant-pathogen interactions serve future innovations in crop protection? I firmly believe that work we’re doing as a research community is important for future food security. And of course, it’s lovely to work in different countries because you pick up different cultures and learn different languages etc. I think it’s great for personal development. But there’s a big “but”: I don’t think there should be expectation for early career researchers to travel around, nor do I think it is essential to become a good researcher. To highlight this, my former mentor and PhD supervisor, Corné Pieterse, did his degree and PhD in Wageningen after which his biggest move was to travel 25 miles from Wageningen to Utrecht to continue his career there. But if you see how successful he is and how incredibly original and ground-breaking his research has been over the years, it tells me that you don’t need to travel around. It’s not always possible for everyone to travel around. I know a lot of very talented people who would love to stay in academia, but they don’t like the prospect of having job insecurity up until their late 30s. I think we should look at that as well and consider the opportunity to work in different countries as a personal choice rather than a must. There are certainly benefits to this nomadic lifestyle, but there are also costs. After all, you have to settle down and adapt to different cultures, different labs, etc., which takes time. So, I don’t think this is something that needs to be enforced. But, yes, for me personally, I very much value my international experience.
A: For our younger audience, is there one piece of career advice that you received during these years that you would give to any young person who started doing science recently? What is one piece of advice that you always give?
J: It’s a very straightforward question, but it’s not very easy to answer. I can give a personal answer based on my own experiences and perspectives. What always worked for me is to follow your own interests and not necessarily the prevailing directions in the field. We previously talked about microbiomes, and while they’re wildly fascinating and popular at the moment, the field has some serious growing pains that must be addressed. While I’m sure that we will get there in the near future (so watch that space), it was far more rewarding in my career to more or less ignore the fashionable trends in the field and focus on the stuff that I found personally very interesting. I was always that person who was unaware of the latest big Science paper in our field because I was reading other papers that interested me, sometimes quite far removed from my home discipline of plant pathology. So, my advice is to follow your own intuition and do what you are truly and passionately interested in, rather than following the direction of travel within the field. If you want to be ahead of the curve and come up with original ideas and new discoveries, you won’t get there by copying the research from other labs. I’ve always followed my own intuition, and if if you stick to it (and do it right), sooner or later, you’ll find yourself in a situation where it becomes very fashionable. This certainly happened with plant stress memory, which in one way is very rewarding, but it can also be somewhat intimidating and at times even frustrating. Suddenly, a lot of people are working on plant stress memory and priming, and you see a lot of papers and grant proposals that make the same mistakes that we made 10-15 years ago. So, to cut a long story short, my advice is to follow your own intuition and personal interests and don’t be afraid to move out of your comfort zone.
A: That’s a very nice ending to our conversation. Thank you very much for agreeing to do this!
Read more interviews of Plant Physiology editors here.
About the author
Aida Maric is post-doctoral fellow with Prof. Sjon Hartman at CIBSS and the University of Freiburg, Germany; interested in epigenetic regulation of stress memory. She obtained her PhD from CRAG, Barcelona under the supervision of Prof. Paloma Mas, where she studied the interaction of the circadian clock and epigenetics. Currently, she is working as assistant features editor of Plant Physiology for the term 2023-2024.