Tissue stem cells require intrinsic and local regulators; however, it is their ability to sense and respond to changes in whole-body physiology and nutrient availability that allows them to function in harmony with varying demands and constraints faced by multicellular organisms. We pioneered using Drosophila melanogaster as a model to study adult stem cell regulation by diet, and identified cellular and molecular pathways that link diet to stem cells. Drosophila offers many advantages as a model system, including highly evolutionarily conserved developmental and metabolic processes, and well-characterized stem cells. In particular, we take advantage of the germline stem cell (GSC) lineage in the Drosophila ovary, where one can readily identify GSCs and quantify self-renewal, proliferation, differentiation and survival along their lineage. Our research showed that GSCs and their progeny divide and grow faster on a rich diet, partially via insulin, steroid hormone, and Target of Rapamycin (a nutrient sensor) signaling in the ovary. More recently, we showed that adipocytes also contribute to the GSC response to diet, which is particularly relevant in light of the current obesity epidemic and the link between dysfunctional adipocytes and a number of diseases, including cancers. We are currently investigating the mechanisms underlying adipocyte-GSC lineage communication, and we are also exploring the connection between brain signals (involved in sensing a variety of environmental and physiological stimuli) and stem cell function. Our more recent work opens a new frontier in our research, aimed at elucidating how multiple organs communicate with each other to orchestrate a cogent response of the organism as a whole to changing conditions.
Weaver, L. N., Drummond-Barbosa, D. The nuclear receptor Seven up functions in adipocytes and oenocytes to control distinct steps of Drosophila oogenesis. Under review.
Drummond-Barbosa, D. Local and physiological control of germline stem cell lineages in Drosophila melanogaster. Genetics (in press).
Weaver LN, Drummond-Barbosa D. Maintenance of Proper Germline Stem Cell Number Requires Adipocyte Collagen in Adult Drosophila Females. Genetics. 2018 PMID: 29884747.
Armstrong AR, Drummond-Barbosa D. Insulin signaling acts in adult adipocytes via GSK-3β and independently of FOXO to control Drosophila female germline stem cell numbers. Dev Biol. 2018 PMID: 29729259.
Matsuoka, S., Armstrong, A. R., Sampson, L. L., Laws, K. M., Drummond-Barbosa, D. Adipocyte metabolic pathways reprogrammed by diet control the female germline stem cell lineage in Drosophila melanogaster. Genetics 206:953-971, 2017. This paper was chosen by the Genetics Editors as one of the June 2017 Genetics issue Highlights.