Mere Minnow Gives Mighty Medical Insights

Developmental biologist Joshua Bloomekatz uses zebrafish to probe origins of heart cells

UM biologist Joshua Bloomekatz is using tiny zebrafish to break new ground in understanding how hearts develop in embryos. The work has potential to advance prevention and treatment of conditions such as congenital heart disease. Submitted photo

OXFORD, Miss. – If you want to understand a fundamental mystery of life, look no further than a 2-inch fish.

Using zebrafish, a freshwater breed that’s in the minnow family, to understand how hearts develop in embryos, University of Mississippi biologist Joshua Bloomekatz is breaking new ground.

His research focuses on the formation of two types of embryonic heart cells: some will become the muscle cells that pump blood from the heart; others will develop into cells that become blood vessels.

“In the beginning of heart development, the cells come together as a tube for pumping blood,” said Bloomekatz, an assistant professor in the UM Department of Biology. “Then the cells develop ‘identities.’ They separate into myocardial (muscle) cells and the endothelial (blood vessel) cells that line the heart.”

Seeing how cells come to “specialize” helps developmental scientists such as Bloomekatz discover how embryos develop from a single cells into complex beings, such as humans.

Zebrafish make excellent subjects for cardiac research because they are translucent and develop externally, away from the mother.

Using the biology department’s laser-scanning confocal microscope, the highest standard in confocal microscopes, Bloomekatz is able not only to get crisp images of zebrafishes’ embryonic heart cells, but also to see them move in real time in short videos produced by his lab.

“If we understand how the process works, we can also understand how it doesn’t work,” he said. “This brings us closer to comprehending why conditions like congenital heart disease occur – and we can make significant advances in both prevention and treatment.

“The cells in the heart will be with you for the rest of your life. Our heart cells do not renew themselves very well, so the cells you have at 14 will be the same you have at 84. That’s why you have to take really good care of your heart.”

Bloomekatz joined the Ole Miss faculty in 2017.

“I wanted to do research at an R1 university,” he said, referring to UM’s rank as a leading U.S. research institution.

He arrived on campus after completing a postdoctoral program in the Division of Cardiovascular Medicine at the University of California at San Diego School of Medicine, one of the nation’s leading research programs of its kind. He earned a bachelor’s degree from the University of California at Berkeley and his doctorate from Weil Cornell Medical College, the medical school of Cornell University.

“Dr. Bloomekatz is an exceptional biologist, whose research is greatly expanding our understanding of heart development,” said Gregg Roman, chair and professor of biology. “His scholarship and mentoring are truly invaluable contributions to the University of Mississippi.”

Bloomekatz teaches both graduate and undergraduate students. Last fall, when he taught a 500-level class about using advanced microscopes such as the confocal scope, his class included eight undergraduates.

“Students learn the proper techniques by working on their own research projects,” he said.

In his classes, Bloomekatz facilitates students’ curiosity about the biological world and supports their diverse career paths in health sciences.

Undergraduate students are integral members of his lab, participating in all aspects of the research process from experimental design to manuscript preparation and presentation, he said.

“I want students to be connected not only to the course material and research techniques but to a supportive intellectual professional and personal community where they learn to think critically and become citizen scientists,” Bloomekatz said.