Your work focusses on understanding how tissues are maintained, repaired and how tissue integrity is prolonged. What makes you the most excited about this research field?

I’m most excited about finding treatments that aid recovery in patients with tissue injury or those living with diseases that cause chronic tissue damage, particularly stem cell-based therapies.

When cells within tissues get damaged or lost, they are often replenished by stem cells. Thus, a tissue’s ability to sense damage and stimulate stem cell proliferation is vital to reinstate its structural and functional integrity. Despite how important tissue regeneration is for organismal survival, it is still poorly understood.

To understand this better, our lab uses the adult Drosophila (fruit fly) intestine, which is an outstanding model to study stem cell-based epithelial regeneration and our own intestinal biology. Like our intestine, the adult fly intestine is maintained by intestinal stem cells (ISCs) that divide to produce the same two main cell types. Fly and mammalian ISCs also use many of the same molecular cues to promote their self-renewal, proliferation and differentiation. From our work in flies, we aim to determine how stem cells respond after tissue damage and hope to learn how to control stem cell behaviour for stem cell-based therapies.

You studied in the USA and did your post-doc in Germany before coming to the UK. What are the main differences you encountered moving to different countries and could you describe your academic journey?

I started my career in science studying chemistry as an undergraduate at the University of Chicago. I enjoyed studying chemistry, but I didn’t see myself becoming a chemist. As I was finishing my degree, I started to become more interested in biology, particularly neuroscience. And when I applied for PhD programmes, I wanted to be a neurobiologist. I was accepted into a PhD programme at the University of California, Los Angeles (UCLA), but after rotating in a few labs, I didn’t join a neurobiology lab. Instead, I joined a lab that studied the development of the Drosophila embryonic hindgut (large intestine). We wanted to understand how a group of cells rearranged themselves to form a tube. I started my PhD by performing a screen to identify additional genes required for hindgut development. One day, I came late to lab, and I looked at my screen only to find that many of the embryos had hatched into larvae. While there were many embryos still left to analyse, I found that the larvae had enlarged hindguts. I immediately called my advisor to the microscope, and she confirmed my observation. She asked me to clone this gene that caused tissue overgrowth. I had discovered the small GTPase

Rheb, which I found to promote cellular growth by activating TOR signalling. So, sometimes great discoveries come from not coming to the lab on time.

Subsequently, I studied how TOR signalling, particularly in muscle, influenced the organismal response to oxidative stress.

As it is important in US academia for science trainees to move institutions and change research areas following their PhD, I moved to Seattle to work with my postdoctoral advisor, Prof Bruce Edgar. Bruce encouraged me to work on intestinal stem cells (ISCs) in the adult fly intestine (midgut), which had only been recently identified at that time. I became curious whether damaging the fly intestine could lead to a regenerative response from ISCs. I found that ablating gut enterocytes caused ISCs to proliferate and replace lost cells after damage. I believe I was one of the first to see this beautiful process under the microscope. I feel very fortunate to have seen this system being understood and developed from an early timepoint. Working with other postdocs in the lab, our lab described one of the first mechanisms of how the adult midgut epithelium regenerates after damage. This process is now studied by many labs around the world, including my lab here in Bristol.

After that, I wanted to take the field in another direction. I became interested in how tumour cells interact with their neighbouring normal epithelial cells. While I was working on this project, Bruce moved to the University of Heidelberg and the German Cancer Research Center in Heidelberg, Germany. Thus, I joined his new lab there, where the bulk of this project was completed. When I was a young boy in Illinois, I thought it would be amazing to move to California one day. But now I was moving to Europe! In this study, I found that tumours grew in the midgut epithelium by displacing and killing the surrounding normal epithelial cells and by co-opting mitogenic signals produced by these stressed or dying cells.

Finally, I returned to studying midgut regeneration, particularly the role of damage-induced reactive oxygen species (ROS) in this process (a focus of my lab now). However, I moved to Bristol and CMM in 2019 as an Elizabeth Blackwell Institute for Health Research (EBI) Early Career Fellow and finished up this work here. This work described one way how damage-induced ROS set up a regenerative niche in the midgut. I then started my own lab here after being awarded a Sir Henry Dale Fellowship from the Wellcome Trust and Royal Society in 2020. I have to thank Profs Eugenia Piddini and Anne Ridley for these opportunities. CMM would not have been a host for both fellowships without them. I also thank the EBI and the Wellcome Trust for their support of our lab.

As you can see, I have worked on various biological questions and in different locations throughout my scientific career, and I highly encourage young scientists to do the same.

What challenges did you face advancing your career as a person from an underrepresented minority ethnic group in academia?

There are many challenges that racial minorities face in academia. I will mention a few below, but many of these apply to any underrepresented group.

I think the lack of mentorship is one of the biggest challenges for racial minorities. There is no one really looking out for you or guiding you. It’s been difficult for me to find quality mentorship. My parents were also not sure how to provide support as they were new to the West. I mainly figured things out by making every mistake possible and learning from it.

Another challenge is the lack of diverse hiring committees. It has been my experience at every interview for an academic position where the interview panel did not contain racial minorities, I did not receive an offer. I think requiring diverse hiring committees and unconscious bias training or tests just before hiring or promotion decisions could help.

Both of these are partly due to the lack of diversity in academia. I often feel like an alien from outer space. In my field (fly gut), I am one of the only PIs with dark skin. I don’t always feel equal or included or seen. However, I am really lucky to have many great colleagues here at CMM, who make me feel more equal, included and seen.

For racial minorities, I think the acknowledgement of racial discrimination is imperative to tackle these challenges. While certain forms of discrimination or bias are more acknowledged, discrimination by race is usually not.

What can we do as a research community to ensure that students and staff from underrepresented minority ethnic groups succeed in academia? Are there any initiatives or policies implemented by the University of Bristol that you think can be effective for this?

There are a few university initiatives that I am aware of, but I don’t know how effective they will be. Overall, there doesn’t seem to be an actionable plan to hire individuals from underrepresented groups.

I have worked with the School EDI committee to identify key challenges faced by racial minority groups in academia. Together with Kaltun Duale (formerly in Adam Finn’s group), we held Wellcome Trust-style Café Culture sessions for students and staff from diverse underrepresented racial backgrounds. These Café Cultures were attended by group leaders, postdoctoral fellows, postgraduate students and technicians. The participants identified 13 challenges faced by racial minority students and staff, and numerous solutions were suggested. These discussions have already helped shape the university further. For example, the university will discontinue the use of “BAME” to collectively describe racial minorities and encourages us to speak about each specific group and their unique struggles.

The ongoing work to decolonise the curriculum could also help. The current curriculum denies that science was a global discussion for centuries. This could be discouraging to racial minorities in science and create biases during hiring and promotion.

As I previously mentioned, better mentorship and more racial diversity on hiring committees would help.

Q&A 

· How do you keep work-life balance? 

Here are two things I do:

1. I take care of my health. I attend a boot camp class, or I work out at home. I occasionally do yoga or meditation too.

2. My family in the US is very important to me. I have a standing video call with them every week to catch-up with them.

· What was the most difficult decision in your career? 

The most difficult decision in my career was to move to Europe as I was leaving behind my family, friends and everything I knew back in the US. But I do not regret the decision. Europe now feels more like home than the US although I do dearly miss my family and my US friends and colleagues. One becomes a world citizen when you work in academia. I have good friends and colleagues around the globe.

· If you could change something in the academic system, what would you do first? 

I would remove competition. Imagine where our civilisation would be if we would actually work together rather than compete with each other.

· What is your favorite thing about being a researcher?

I like all of it, but I particularly love problem solving, forming new hypotheses, and devising ways to test them. This the most creative part of science, and it allows me to feel like an artist.

·  Would you have any advice on building a supportive network in academia?

Networking can feel like a challenge. It’s hard to feel respected and accepted, especially if you are different. But do go to meetings and talk to people. You will see that there are many people open to talking to you. I started building my network as a PhD student. I made my first network connection at a meeting in Switzerland. We have been good colleagues and friends since, and we are currently planning a collaborative project together.