“Seize the chance – it’s worth it!”

What is your PhD project? 

I studied physics but wanted to shift toward biology. I had a computational background when I arrived in the Metzger lab. But the lab was just starting up, so I didn’t have a lot of data to analyze at first. I wound up switching projects a lot and then became interested in very early neural development – how neurons are born and in which order. In other words, what type of neurons are being generated and by what progenitors. To pursue those questions, I also had to learn the skills of a wet lab scientist. 

How did you find a PI as part of the exchange? 

I looked for PIs whose research field overlapped with my interests. I found Esteban Mazzoni at NYU Langone Health who studies neuronal differentiation. In addition, a friend and colleague in the exchange program who had met Mazzoni recommended him. I had several Zoom calls with Mazzoni to plan the research I would be doing in his lab and it was him that brought up the idea to do lineage tracing in neuronal tissue.  

With a view: The entrance area to NYU's School of Medicine.

© Philipp Roth, Max Delbrück Center

What was the plan? 

We came up with the idea of performing lineage tracing in human brain organoids. I would establish a protocol for a new cell lineage tracing method at MDC-BIMSB and then perform an experiment in Mazzoni’s lab on human stem cells. One of Mazzoni’s research interests is studying how stem cells eventually become spinal cord cells. We wanted to use the lineage tracing to identify which progenitor cells mature into spinal cord cells.  

How did your plan unfold? 

We wanted to develop lineage tracing in a cell line and validate the method at MDC-BIMSB. But the process turned out to be more difficult than we had thought. I was trying to integrate a system to generate random barcodes into the genome of stem cells. To accomplish this, we had to create a plasmid containing this system. Once stem cells are barcoded, you can track their progeny as they develop into mature tissues. In New York, I was able to create a cell line with the integrated barcode. But unfortunately, at the very end of my stay the cells got contaminated and I wasn’t able to perform any of the experiments I had planned or take the cells back to MDC-BIMSB. 

Were you disappointed? 

Scientifically, it was disappointing in a way, but only because we had bad luck and the cells got contaminated in the end. But of course, science is full of failed experiments especially when dealing with very delicate cells. Nevertheless, I did learn the protocol to differentiate stem cells into motor neurons and I also now know that the integration of my barcode into the cells works. Now, Mazzoni’s lab is using some of the plasmids I brought for other types of research. I also got better at reaching out for help in an environment where I didn’t know anyone. 

Philipp Roth doing his research at MDC-BIMSB.

© Felix Petermann, Max Delbrück Center

What are you working on now? 

Thanks to the program, I earned funding for an additional year to finish my PhD. Normally, PhD contracts are three years, even though most of the time students need longer. I am now focusing on a second project at MDC-BIMSB, which is more computational. The lineage tracing project is being continued by my colleagues in Berlin.   

What advice would you give future candidates? 

Be proactive and push for it at the earliest stage possible, even if plans aren’t perfectly outlined. The program provides financial and administrative support, but you drive the actual organization and project. Take responsibility, be your own boss and stay determined. Even though my plan didn't work like I wanted it to, I pushed through. There are so many other great things that I got out of the experience that I did not anticipate. Seize the chance—it’s worth it. 

Based on your experience, is there anything you would have done differently? 

I think I started looking for a collaborator far too late. By the time I found Mazzoni, I was already two years into my PhD program. Doctoral students should start contacting PIs as soon as they start so they have enough time to find the right person and plan the research. Don’t be afraid to reach out without a plan, often by talking to another PI, new project ideas might come up. 

Philipp Roth's daily check-in for research.

© Philipp Roth, Max Delbrück Center

How will this experience help your career, whether in academia or industry? 

The connections I made can open doors, particularly if I decide to do a postdoc. If I go into industry, this international experience will be a strong asset on my CV. I’m leaning towards data science, where remote work and job opportunities are plentiful. 

Did you enjoy your time living in New York? 

I lived in multicultural Bushwick, Brooklyn where I experienced a diverse Latino culture that was new and interesting to me. I also very much enjoyed the huge and diverse culinary options New York has to offer. I am a hobby musician and had already made some contacts in NYC through my music. I was able to connect with them in person and was invited to DJ in a few venues. It was a rich, enjoyable personal experience outside of work. On top of that my English improved, and I made many meaningful connections and new friends. 

Interview: Gunjan Sinha