In light of the symposium on Development and Morphogenesis in honour of Maria Leptin, I was asked to reflect on my interactions with Maria. I worked as a PostDoc in her lab at the University of Cologne and subsequently became editor at EMBO Press.

First encounters

I arrived at the Genetics institute in the summer of 2006 to present my PhD work to Maria and the other members of the institute. My research on early eye morphogenesis at the EMBL had sparked my interest in early embryonic development, including the cellular interactions and movements that take place during gastrulation and neurulation. Maria’s pioneering work on Drosophila gastrulation had captivated me, and inspired me to apply for a postdoctoral position in her lab. During this initial meeting, Maria's ability to ask precisely targeted questions left a lasting impression on me.

I had worked on zebrafish and medaka before, but these vertebrate model organisms had limited options for genetic manipulations at that time. When I delved into the realm of Drosophila genetics, I found myself in uncharted territory. My new colleagues handed me vials containing flies with the remark ‘gene X over TM6b’ or ‘E-cadherin-GFP over TM3’. This information left me clueless, as I had no idea what these mysterious “TM’s” referred to or – Drosophilists, please stop reading here! – on which chromosomes those genes were. Over time, I learned the secrets of ‘balancer’ chromosomes to prevent recombination and loss of your marker from the sister chromosome, and figured out that TM6b was a balancer for the third chromosome. I learned about markers to screen for the presence of the balancer chromosome such as body color and bristle phenotypes, and how to plan a genetic cross. And whenever I got lost in the mist of Drosophila genetics all that was needed to resolve my confusion, was to enter Maria’s office and ask. She has always been, and continues to be, a living encyclopaedia for Drosophila mutants, genotypes, and genetic tools. She knew whom to approach or collaborate with, as well as which books to consult, in order to find the answers I sought.

Over the course of nearly 9 years collaborating with Maria, I have observed several attributes that define her and her work, all of which have had a profound impact on my personal development and my career: Creativity, Freedom, Critical thinking, Thoughtfulness, Networks, Mentoring, Energy.

Creativity and Freedom

As a trained immunologist Maria started working on fruit flies and gastrulation while she was a group leader in Tübingen. She didn’t stop there but kept coming up with new ideas and new questions to ask, expanding her research portfolio to fish immunity and tracheal tube formation in Drosophila. As a member of her lab, we always had the freedom to be creative, start new projects and think ‘out of the box’. This experience greatly helped me when I decided to proceed with a career as scientific editor, broadening the research topics I was exposed to in my work.

Critical thinking and Thoughtfulness

“You do not prove a hypothesis, you test it”, is how Maria approached science in her lab – not only when she analyzed results from lab members but also when she edited and wrote a manuscript. I remember proudly sending the first draft of my manuscript to Maria only to see it turned upside down.  Are there alternative explanations possible? Do the data allow us to make these conclusions, or do we need to perform additional experiments to challenge or verify that claim? These detailed critical comments seemed tedious at times, but it was highly valuable as it resulted in a stronger manuscript with well-supported claims.

Networks and Mentoring

As a scientific editor it is important – and also a fulfilling aspect of the job – to establish and maintain a vast network with other scientists. Working with Maria provided a vivid example of how to do it, as she was very engaged in keeping in touch with scientists she met during the course of her work and with former lab members. It allowed me to establish collaborations and to organize training visits to the lab of Eric Wieschaus in Princeton to learn new techniques or to the lab of François Schweisguth at the Institut Pasteur. Maria’s extensive network was also very helpful when we expanded our tools to microarray experiments – the method of choice before RNA-seq was developed – in order to identify targets of the transcription factor Snail.  I manually collected embryos at cellularization stage en masse and remember that these left an imprint on my retina so that I kept seeing them when I closed my eyes at night. In collaboration with the lab of Eileen Furlong at EMBL we found that the transcriptional repressor Snail, an essential player in gastrulation, could also activate a subset of target genes. All collaborators mentioned will be speakers at the upcoming symposium.

Energy

Last, but certainly not least, I remember her great energy for science, for ballet and for yoga – I think she never missed a class, no matter how busy she was – and for organizing social events. Unforgotten the wine tastings at her house: 25 ml per wine for each person, carefully measured with a Falcon tube. Undoubtedly one of the best uses for Falcon tubes I know of!

Thank you, Maria for being a mentor during these times and I am looking forward to the symposium.

Photograph from Maria Leptin