Alexis Maizel

Alexis Maizel is a Cell and Developmental biology professor at Heidelberg University in Germany. Born in the north of France, he studied biology, mathematics and physics in Lille and Lyon. He joined the laboratory of Alain Prochiantz at the Ecole Normale Supérieure in Paris, where he obtained his PhD in 2002 working on the cell biology of homeoproteins and their role in the development of the nervous system. He switched model, topic and continent for his postdoc and joined Detlef Weigel to work on the evolution of floral development originally at the Salk Institute in San Diego and later at the Max Planck Institute for Developmental Biology in Tuebingen, Germany. After a short stint in 2005 at Cold Spring Harbor Laboratory with Dave Jackson, in 2006 he joined the RNA and Root Development team of Martin Crespi at the CNRS Plant Science Institute in Gif-sur-Yvette, France. In 2010, he started his independent team working on plant morphogenesis at the Center for Organismal Studies at Heidelberg University, where he became a full professor in 2020. Passionate about microscopy and development, he has co-organised several EMBO practical courses on plant imaging and since 2017 coordinates a DFG-funded research network on plant morphodynamics (www.plantmorphodynamics.com). His research interests lie in understanding the physical, cellular and molecular principles responsible for the morphogenesis of lateral roots in Arabidopsis. What turned you on to biology in the first place? Mine is not a story of a childhood passion for nature and hunting butterflies. Apparently, from a young age, I loved sciences and wanted to be a researcher, but not necessarily a biologist. Yet, I remember how, as a kid at school, I was very impressed by looking into a microscope and discovering the complexity and beauty of cells and tissues. This was an eye-opener for me. That there was an artistic component to studying biology through the numerous drawings we had to do was also motivating and appealing. I quickly became passionate about understanding the complexity of living systems, how these machines function, and how they shape themselves in development. And what drew you to your specific field of research? Oh, this was a meandrous route. During my undergraduate studies in the late 90s, I was very interested in developmental biology and, in particular, the development of the nervous system. I thus joined the team of Alain Prochiantz in Paris to work on the role of homeoproteins in the development of the nervous system in mice. The lab was studying an unconventional mode of action of these transcription factors — their direct transfer from cell to cell as a means to convey positional information. I mostly worked with a cell culture model for this process, which fueled my interest in cell biology. The neighbouring lab was working with Drosophila, and I was envious of the genetic toolbox that allowed them to do fancy cell biology in a whole organism (which back then was difficult to do with rodents), and this motivated me to change model for my postdoc. Then I stumbled onto a paper in Nature (Parcy et al. 1998) describing the genetic framework responsible for flower formation in Arabidopsis. That was it! An in vivo model to study the morphogenesis of a beautiful structure with a solid genetic toolbox. So, I joined Detlef Weigel’s lab at the Salk Institute with nearly zero background in plant biology. There, I met a terrific bunch of colleagues, most of whom were not trained as plant biologists, and I studied the evolution of the function of the master gene for flower development in the green lineage. I got hooked on plant development, and for my independent career, I started to concentrate on root development — first in France, where I joined Martin Crespi’s team and worked on non-coding RNAs and their roles in root development, then in Heidelberg, Germany, where I shifted the lab’s focus to the study of lateral root morphogenesis. Which area of biology do you find most exciting? Anything related to a mechanistic understanding of morphogenesis. How genes and their products modify cell properties that, in turn, modify tissues and lead to the emergence of defined shapes. The intersection of physics and mechanics with molecular and cell biology excites me. I read or heard that development is a genetically encoded solution to a physical problem. I find this definition very appealing, and frame my research in this context. What motivates you? Trying new things, opening to other (scientific) cultures, and breaking the routine. For example, I was recently in a podium discussion with an artist working with roots and plants, and this encounter with a very different world was super exciting. It forces you to look at what you do with different eyes. I also find it highly motivating and rewarding to convey my enthusiasm for research to students and the general public. Which historical scientist would you like to meet, and what would you ask them? The authors of two books. One is Stephen J. Gould, the author of Ontogeny and Phylogeny, which I read during my undergraduate studies. The second is D’Arcy Thompson, the author of On Growth and Form, which I read a couple of years ago. I would be excited to meet these scientists and discuss their work. Getting to know what fascinated them would’ve been extremely interesting. What is your favourite conference? I really like small conferences or workshops with an interdisciplinary focus. The recent workshops “Physics of Plant Growth” held in Israel and “Multiscale Modeling of Plant Growth, Pattern Formation and Actuation” in Mexico were extremely exciting. Otherwise, one of my favourite plant biology conferences is the FASEB on Mechanisms of Plant Development, which I will be honoured to co-organise in 2025. What is your greatest ambition? I hope that our work on lateral root development leaves a dent in what is currently known and will contribute to our understanding of plant development. More importantly, I hope that I will have managed to pass on to others, students or colleagues, some of my passion for understanding developmental processes and mixing imaging, molecular biology and quantitative approaches. I also hope that in a few years, looking back at what I have done, I can be proud of staying true to myself and what I burn for. What makes you angry? Some would say many things get me angry, but the main thing is when people judge others according to certain principles, but refuse to apply them to themselves. Which aspect of science, your field or in general, do you wish the general public knew more about? Plants are fascinating organisms that do many things better than animals — photosynthesis, regeneration, and processing information without a nervous system, to name a few. Also, people don’t necessarily realise that even though they’re sessile, plants are definitely not motionless, and their peculiar mode of development is one of the secrets to their adaptability. What are the big questions to be answered next in your field, and what are science’s most significant problems facing today? When and how do cells know to stop growing? What is responsible for the robustness in organ size? These are, for me, fascinating questions certainly not specific to plant developmental biology. Yet, because plant cells are so tightly bound to one another, they may resort to specific mechanisms. Linked to this is to understand how the modification of molecular properties at the cell scale, such as cell wall mechanics and signalling, relates to the emergence of complex responses at the tissue scale. Tackling the emerging behaviour of this complex system is fascinating. If you had not made it as a scientist, what would you have become? I probably would’ve become an architect or some other profession with a mix of technical aspects and artistic sensibility. Luckily, I find these two aspects in my current work, so I have no regrets. How do you balance your work with other things in your life? As much as possible through efficient time management and discipline. Even if I can work for long hours on a project or manuscript, in the long run, I need to change and focus on non-work-related things. I allocate blocks of time to the different facets of my life. For example, I refrain from checking emails or messages in the evening or on weekends to have clear separation. I noticed that this separation did not prevent background thinking about science, and it actually allowed ideas to emerge. Even if it is not a perfect system, it is working. What are your passions in life outside the lab? I’m an enthusiastic triathlete and regularly compete nationally and internationally. The long hours of training help achieve the work–life balance mentioned before. I also enjoy playing music very much. I have been mixing music as a DJ for some time — I play for parties, in small clubs and sometimes even at scientific conferences! The author declares no competing interests.