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Department of Neuroscience

William Ja, PhD

Scripps Research Affiliate
Department of Neuroscience
Florida Campus
Laboratory Website
(561) 228-2956

Scripps Research Joint Appointments

Faculty, Graduate Program

Research Focus

Over a century of research on the fruit fly has resulted in profound discoveries in basic cellular processes, and has enabled the use of Drosophila as a model for human disease and drug discovery. Our laboratory uses diverse tools in chemistry and biology to dissect genetic pathways that are involved in aging and behavior. We are currently involved in several major directions:

  1. Interactions of symbiotic microorganisms with Drosophila
    Our studies establish the molecular relationships between the fly-associated microbes, nutrition, and host health and aging. Projects include phylogenetic and genomic studies, analyses of host and bacterial gene expression, and genetic manipulation of candidate host mechanisms for modulating the gut microbiota.
  2. Genetic pathways involved with aging and nutrition
    We have identified candidate genes that modify lifespan in response to nutrition, mimicking the effects of dietary restriction. The mechanistic analysis of these genetic pathways includes application of large-scale methods (metabolomics, lipidomics) and gene expression studies on Drosophila mutants. We are also investigating small molecule-modulators of mitochondrial function in cell culture models of aging.
  3. Drosophila feeding behavior
    We are 1) developing simple tools for measuring short- and long-term food consumption in flies and 2) characterizing genetic mutants with abnormal feeding behavior.  This work will provide a better understanding of the central genetic and neuronal mechanisms that underlie appetite and feeding.


B.S., Chemistry, University of California, Berkeley, 1998
Ph.D., Chemistry, California Institute of Technology, 2004

Awards & Professional Activities

2011-2015 Ellison Medical Foundation New Scholar in Aging Award
2010 Glenn Award for Research in Biological Mechanisms of Aging
2008-2013 NIH Pathway to Independence Award (K99/R00)
2007 DeLill Nasser Award for Professional Development in Genetics
2005-2006 John Douglas French Alzheimer's Foundation Postdoctoral Fellowship
2004 Glenn Foundation/American Federation for Aging Research Scholarship
1998-2001 DOD National Defense Science and Engineering Graduate Fellowship
1998 Erich O. and Elly M. Saegebarth Prize in Chemistry
1998 Waldo Semon Undergraduate Research Award 1997-1998 Barry M. Goldwater Scholarship

Selected References

Obadia B, Güvener ZT, Zhang V, Ceja-Navarro JA, Brodie EL, Ja WW, Ludington WB. Probabilistic invasion underlies natural gut microbiome stability. Curr. Biol. 27, 1999-2006 (2017).

Park JH, Carvalho GB, Murphy KR, Ehrlich MR, Ja WW. Sucralose suppresses food intake. Cell Metab. 25, 484-5 (2017).

Murphy KR, Deshpande SA, Yurgel ME, Quinn JP, Weissbach JL, Keene AC, Dawson-Scully K, Huber R, Tomchik SM, Ja WW. Postprandial sleep mechanics in Drosophila. Elife 5, e19334 (2016).

Yamada R, Deshpande SA, Bruce KD, Mak EM, Ja WW. Microbes promote amino acid harvest to rescue undernutrition in Drosophila. Cell Rep. 10, 865-72 (2015).

Deshpande SA, Carvalho GB, Amador A, Phillips AM, Hoxha S, Lizotte KJ, Ja WW. Quantifying Drosophila food intake: comparative analysis of current methodology. Nat. Methods 11, 535-40 (2014).


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