Dan’s introduction to Hailey’s public dissertation seminar, March 1, 2023:

Thank you all for being here to support and celebrate Hailey. Hailey is a joy to work with. She made crucial contributions to the lab in terms of assay development and optimization. Hailey’s ability to design and execute experiments outside of our lab’s comfort zones, and to optimize and improve existing experimental approaches, demonstrates her resourcefulness, confidence, and ability to succeed in the lab. She has an affinity for microscopy and has become an expert at brightfield, fluorescence and confocal microscopy, to the point that other lab members ask for her advice.

Hailey is laid back, cool and unflappable. It takes a keen, practiced eye to see when Hailey is angry or disappointed, and you will never, ever see her sweat.

Underneath the cool, laid-back exterior is a tenacious, confident interior. Through every set back and unlucky break, Hailey persisted. She joined my lab in May 2016, when I was faculty at the University of Alabama in Birmingham and Hailey was a neuroscience graduate student. She completed her class work and passed her oral qualifying exam. In 2018, my lab moved to Baylor College of Medicine, and Hailey moved with me. She transferred to the Baylor molecular and cellular biology graduate program. Transferring programs meant that she had to take additional classes and take, and pass, another oral qualifying exam. Meanwhile, we had moved our zebrafish from Birmingham to Houston, and they didn’t adjust well to their new home. Six months after we moved, we lost almost half of our zebrafish colony. This severely impacted Hailey’s research and contributed to Hailey’s decision to switch projects. All this during a time when some prominent politicians were turning a blind eye to, or even openly encouraging, white nationalism and attempting to restrict women’s rights. What a difficult and stressful time to be a student. And as if all that wasn’t enough, along came COVID.

Nevertheless, Hailey persisted.

Hailey discovered that zebrafish with homozygous mutations in both arnt1 and arnt2 genes lack blood cells and have poorly developed blood vessels. Hailey discovered that arnt1 and arnt2 were required for the formation of progenitor cells that are fated to become blood cells or endothelial cells. Prior to Hailey’s observation, there was only one gene known to be required for the formation of hemato-vascular progenitor cells, a transcription factor called npas4l. Through rigorous and detailed phenotypic analysis at the anatomic, cellular, and genetic levels, Hailey discovered how mutations in arnt1/2 double mutants, but not single mutants, cause hemato-vascular abnormalities. I can’t stress enough the diligence required for these experiments. Breeding double heterozygous animals to each other results in a low percentage of progeny that are double homozygotes (~6%). Even with the advantages of dozens of zebrafish embryos produced per adult breeding pair, Hailey needed to carefully sift through hundreds of embryos to identify the handful of phenotypic mutants, and then carefully collect and prepare them for histologic and genomic analyses. Because the double mutant embryos are so rare, Hailey was forced to push the bounds of several standard approaches and get assays to work using much lower levels of starting material. It has been inspiring for me to watch her dedication.

After Hailey demonstrated that arnt1 and arnt2 are required for the development of hemato-vascular progenitor cells, she then hypothesized that ARNT1 and ARNT2 act as transcriptional coregulators with another transcription factor, NPAS4L. It’s a testament to Hailey’s scientific creativity and fortitude that she designed and performed experiments outside of our lab’s zebrafish comfort zone, using cultured cells and other in vitro biochemical approaches, to demonstrate that ARNT proteins and NPAS4L interact to regulate transcription. I’d like to be able to say that I taught her everything she knows, but that is false. For many of these experiments, Hailey learned the techniques herself, independently, or with help from her peers, and introduced them to the lab so other lab members can benefit from this knowledge in the future.

Another example of how Hailey as grown as a scientist: When she first joined the lab, she rarely asked questions at seminars. Today, Hailey asks a question at almost every seminar she attends. I’ve been complimented by faculty who tell me they wish their students would ask such good questions.

Examples of how Hailey has not grown as a scientist: She is still a terrible speller. Microsoft Word spell check is powerless to fix this. Maybe this will be improved at her next job.

Speaking of her next job, here is another example of Hailey’s success. Hailey interviewed for a faculty job at Belmont University, a liberal arts college in Nashville. This is a testament to Hailey’s skills and ability, that as a graduate student she is competitive for a faculty job. It’s also a testament to her confidence, and passion for research, that she turned down the job and will be doing a postdoc at the University of California in San Diego, because her goal is to become a principal investigator at a research-intensive university. Belmont’s loss is San Diego’s gain.

It takes a village to mentor a student. I want to acknowledge the help I received mentoring Hailey: from Hailey’s thesis committees at UAB and at Baylor College of Medicine, the graduate program director of the UAB neuroscience PhD program at UAB, Karen Gamble, and the director of the BCM MCB PhD program, Tom Cooper, as well as the graduate school administrative support staff, especially Caroline Kosnik. Thanks to staff of the UAB and BCM zebrafish facilities, and the administrators in the BCM Department of Molecular and Cellular Biology and the Center for Precision Environmental Health, especially Neeraj Patel & Yhari Jones. Thanks to my faculty colleagues here at Baylor, at Rice University, at the University of Texas, and at the University of Houston, and the members of their laboratories, too numerous to name, who gave Hailey advice and support.

The final thank you goes to Hailey. Thank you for joining my lab and trusting me with your education. Thank you for moving with me from Alabama to Baylor. Thank you for teaching me how to be a better scientist and mentor. I learned a lot more from you than you did from me. I am going to miss you. Please join me in welcoming – no longer my student, but my colleague – Hailey Edwards, to give her public thesis seminar.