Stephen Lu, Ph.D., is a postdoctoral researcher who recently completed a three-year research project in the Laboratory of Malaria and Vector Research and the Laboratory of Bacteriology through his participation in the Rocky-Beth Fellowship Program. This unique partnership between NIAID laboratories located in Maryland and Hamilton, Montana, allows fellows to work on a research project under the guidance of mentors at both locations. Stephen reflects on how this collaborative experience prepared him for the next stage of his career.
What is the Rocky-Beth Postdoctoral Fellowship Program?
The Rocky-Beth program offers candidates the unique opportunity to collaborate with two distinct research groups, uniting their expertise around a common scientific question. The program's structure not only exposes candidates to a wider array of technical skills but also introduces them to two distinct mentoring styles. This dual mentorship is particularly valuable as it fosters varied perspectives and discussions about the project. Additionally, it aids candidates in developing their own distinct "mentoring voice."
When did you become a Rocky-Beth Fellow, and what principal investigators did you work with?
I became a Rocky-Beth fellow in 2020 under the supervision of José Ribeiro, M.D., Ph.D., chief of the Vector Biology Section in the Laboratory of Malaria and Vector Research (Beth), and B. Joseph Hinnebusch, Ph.D., chief of the Plague Section in the Laboratory of Bacteriology (Rocky). I initially joined Dr. Ribeiro’s group due to my interest in his bioinformatic approach to studying blood-feeding arthropods, particularly the salivary glands of the flea Xenopsylla cheopis. Dr. Hinnebusch, an expert in the flea, also maintained a flea colony in his lab at the Rocky Mountain Laboratories, and we knew we wanted to collaborate with him. When we discovered the Rocky-Beth program, it just made sense to apply for it.
On a personal level, I already knew Dr. Ribeiro before joining his group in 2019. I had some interactions with him during my masters and Ph.D. and was just impressed with his way of approaching questions. In many aspects, he became a mentor role model to me. In contrast, my initial contact with Dr. Hinnebusch was through emails and video calls since my first visit to RML was delayed until 2022 due to the COVID-19 pandemic. However, Joe’s personality is somewhat similar to my own, so after a short time, I was very comfortable talking to him. I think the great relationship that I developed with both my mentors really enhanced my postdoctoral training here at NIAID.
What was the topic of your research?
During my Rocky-Beth fellowship, my research focused on the salivary gland composition of the flea Xenopsylla cheopis, utilizing transcriptomic and proteomic approaches. The goal was to identify salivary proteins with potential pharmacological activity facilitating blood acquisition. This effort yielded a list of potential salivary proteins, and subsequent work led to the characterization of a small protein capable of inhibiting thrombin with high affinity. Recently, we published a paper in Communications Biology on the characterization of three salivary acid phosphatase-like proteins from X. cheopis that we had identified in our first transcriptome. Notably, these proteins, despite bearing structural similarities with acid phosphatases, lack conserved catalytic residues and do not exhibit the enzymatic activity associated with members of this family. Instead, we found them to act as scavengers of small agonists important during the host homeostatic response. Currently, we are working on the first genome of X. cheopis and pursuing other projects involving the body louse Pediculus humanus, which Dr. Hinnebusch also maintains a colony of at RML.
What are your future plans, and how has your experience as a Rocky-Beth fellow prepared you for what you want to do?
I am currently applying for academic positions, and I believe the Rocky-Beth program significantly shaped my training as a researcher. On the technical side, the close collaboration with two research groups boosted distinct areas of expertise. This experience enriched my technical skill set and offered me diverse perspectives on how to approach specific scientific questions. Additionally, I benefited from the exposure to two distinct yet commendable mentoring styles, which will definitely help me find my own “style.”
What advice would you give to fellows interested in applying to the Rocky-Beth program?
Talk to the principal investigators you're interested in working with and find those with whom you are “compatible.” I think that much of my positive experience as a Rocky-Beth fellow was due to the fact that I was able to develop a great relationship with both my mentors. I don’t think I can properly describe how lucky I feel to have worked with both Jose and Joe and how much I learned (and still learn) from them.
See Lu S et al. Identification of a substrate-like cleavage-resistant thrombin inhibitor from the saliva of the flea Xenopsylla cheopis. J Biol Chem. DOI: 10.1016/j.jbc.2021.101322 (2021).
Lu S et al. Integrated analysis of the sialotranscriptome and sialoproteome of the rat flea Xenopsylla cheopis. J Proteomics. DOI: 10.1016/j.jprot.2021.104476 (2022).
Lu S et al. Acid phosphatase-like proteins, a biogenic amine and leukotriene-binding salivary protein family from the flea Xenopsylla cheopis. Commun Biol. DOI: 10.1038/s42003-023-05679-0 (2023).