Margaret McFall-Ngai (born 1951) is an American animal physiologist and biochemist best-known for her work related to the symbiotic relationship between Hawaiian bobtail squid, Euprymna scolopes and bioluminescent bacteria, Vibrio fischeri. Her research helped expand the microbiology field, primarily focused on pathogenicity and decomposition at the time, to include positive microbial associations. She has been a professor at PBRC's Kewalo Marine Laboratory and director of the Pacific Biosciences Research Program at the University of Hawaiûi at MÃÂnoa. In 2022, she moved her laboratory to Caltech, in Pasadena, California.
McFall-Ngai spent her childhood in Southern California and attended Immaculate Heart High School in Los Angeles. She attended college at the University of San Francisco, graduating in 1973 with a Bachelors of Science in biology. She chose to further her education at the University of California, Los Angeles (UCLA) with doctoral advisor, James Morin, studying functional morphology and comparative physiology while working as a teaching assistant/fellow. Her graduate research took her to the central Philippines to study the relationship between bioluminescent bacteria found in the leiognathid light organ in fish, igniting her "lifelong interest" in the blend of the two subjects. McFall-Ngai graduated with her Ph.D. in Biology in 1983 and went on to complete two postdoctoral fellowships. For her first postdoc, she remained at UCLA working on protein biochemistry-biophysics for the Jules Stein Eye Institute with advisor, Joseph Horwitz. She then moved to San Diego to work with advisor George Somero on protein chemistry enzymology at the Scripps Institute of Oceanography at the University of California, San Diego. On the side McFall-Ngai had been exploring the Hawaiian bobtail squid as an alternative to the fish she had studied in graduate school and initiated what would become a career-long collaboration with microbiologist, Edward (Ned) Ruby, who had written his dissertation on the squids' symbionts, Vibrio fischeri.
In 1989, McFall-Ngai accepted a position and later received tenure at the University of Southern California in the Department of Biology and began breeding and studying the Hawaiian bobtail squid. She and Ruby moved to Hawaii in 1996 to better study the squid-bacteria relationship, both accepting positions at Pacific Biomedical Research Center at the University of Hawaii. In 2004, McFall-Ngai accepted a position as professor in the Department of Medical Microbiology and Immunology at the University of WisconsinâÂÂMadison and the Eye Research institute. She returned to Hawaii in 2015 when she accepted the position as director of the Pacific Biosciences Research Program and professor at PBRC's Kewalo Marine Laboratory at the University of Hawaiûi at MÃÂnoa.
McFall-Ngai is a pioneer in the study of animal-bacterial symbiosis and known for her research of the Hawaiian bobtail squid, Euprymna scolopes, and its relationship with bacteria, Vibrio fischeri. She initially began her research in graduate school studying fish with a similar bioluminescent bacterial relationship, however, these fish proved difficult to grow in the lab. At a meeting, a visiting researcher from the University of Hawaii suggested she investigate the Hawaiian bobtail squid and its bioluminescent symbionts V. fischeri as an alternative. McFall-Ngai found that the squid worked great in the lab with 8-10 pairs of squid generating roughly 60,000 juveniles a year. To fully study this relationship, McFall-Ngai began collaborating with Edward (Ned) Ruby, a microbiologist who had written his dissertation on V. fischeri.
Over the next three decades, McFall-Ngai, Ruby, and dozens of postdocs and students would investigate all aspects of the symbiotic relationship. They worked to understand the development of the relationship at different stages of the squid life cycle, analyze the initiation of symbiosis in real time, and identify how the host selects its symbionts. They learned that the squid follows a rhythmic pattern in which the bacteria are brightest when the squid hunt at night and are then expelled at dawn. As analysis tools advanced, Ruby and McFall-Ngai were able to map transcriptional patterns and identify related genes that control the squid's rhythmic behaviors and symbiotic relationship. The sum of their Hawaiian bobtail squid research is an extremely well defined model organism fit for studying bacterial symbioses, light interacting tissues, and cephalopod development.
Source: