Herman A. Dierick, M.D.
Assistant Professor of Molecular and Human Genetics
Assistant Professor, Department of Neuroscience
M.D., Catholic University of Leuven, 1991
Postdoc, University of Michigan, 1997
Postdoc, Northwestern University, 2000
Research Fellow, The Neurosciences Institute, 2007
Aggression is a complex social behavior that is influenced by numerous genetic and environmental factors. Neither the genes underlying this behavior nor its neurobiological mechanism(s) are very well worked out. Much of the aggressive behavior observed in nature is directed towards animals of the same species, so called intraspecific aggression, and revolves around competition for limited resources in the environment, food and mating partners. Most if not all animals show some form of aggression which suggests that the fundamental aspects of aggressive behavior may well be conserved throughout the animal kingdom. Even though aggression is a normal behavior necessary for animals to successfully compete and contributes to the survival of the animal and the species, aggression can also take on pathological forms. Numerous human diseases are characterized by an aggression component.
In the past, we have pursued two angles to start to understand the neurobiological basis of aggression in Drosophila melanogaster. In a first set of experiments, we performed selection on a wild type strain using a very specific selective pressure in a population based environment. We picked animals for further breeding that performed a rare but highly aggressive behavioral element known as escalated fighting in which males reciprocally lunge at each other and box and tussle in order to gain control over a territory. After the selected lines showed reliably different levels of aggression from control strains, we performed micro array expression experiments to look for changes in gene expression in the heads of the high and low aggression strains. This resulted in a list of candidate genes, some of which as individual mutations partially recapitulated the phenotype. In a set of follow-up experiments, we analyzed the effect of two neuromodulators, known to affect aggression in mammals. Both these modulators, serotonin (5-HT) and neuropeptide F (npf) strongly affect aggression in the fly, albeit not exactly in the same way.
Our research goal is to continue to dissect the genetics and neurobiological mechanisms of aggressive behavior in Drosophila melanogaster, using the many sophisticated genetic, cell biological and neurobiological tools that are available in this species. Eventually, we want to investigate whether the mechanisms and genes identified in the vinegar fly are conserved in vertebrate species including mammals.
- Dierick HA (2007). A method for quantifying aggression in male Drosophila melanogaster. Nat. Protoc. 2(11): 2712-8. PubMed PMID: 18007606
- Dierick HA, Greenspan RJ (2007). Serotonin and neuropeptide F have opposite modulatory effects on fly aggression. Nat. Genet. 39(5): 678-82. PubMed PMID: 17450142
- Dierick HA, Greenspan RJ (2006). Molecular analysis of flies selected for aggressive behavior. Nat. Genet. 38(9): 1023-31. PubMed PMID: 16906161
- Greenspan RJ, Dierick HA (2004). 'Am not I a fly like thee?' From genes in fruit flies to behavior in humans. Hum. Mol. Genet. 13: R267-273 (Review). PubMed PMID: 15358734
- Chao AT*, Dierick HA*, Addy TM, Bejsovec A (2003). Mutations in eukaryotic release factors 1 and 3 act as general nonsense suppressors in Drosophila. Genetics 165(2): 601-12. *First authors PubMed PMID: 14573473
- Ostrowski S, Dierick HA, Bejsovec A (2002). Genetic control of cuticle formation during embryonic development of Drosophila melanogaster. Genetics 161(1): 171-82. PubMed PMID: 12019232
- Moline MM*, Dierick HA*, Southern C, Bejsovec A (2001). Non-equivalent roles of Drosophila Frizzled and Dfrizzled2 in embryonic wingless signal transduction. Curr. Biol. 10(18): 1127-30. *First authors PubMed PMID: 10996794
- Dierick H, Bejsovec AM (1999). Cellular mechanisms of Wingless/Wnt signal transduction. In Curr. Top. Dev. Biol. (pp. 153-190), Pederson and Schatten (eds.), New York: Academic Press.
- McCartney BM, Dierick HA, Kirkpatrick C, Moline MM, Baas A, Peifer M, Bejsovec A (1999). Drosophila APC2 is a cytoskeletally-associated protein that regulates wingless signaling in the embryonic epidermis. J. Cell Biol. 146(6): 1303-18. PubMed PMID: 10491393
- Dierick HA, Bejsovec A (1998). Functional analysis of Wingless reveals a link between intercellular ligand transport and dorsal-cell-specific signaling. Development 125(23): 4729-38. PubMed PMID: 9806921
Herman A. Dierick, M.D.
Department of Molecular and Human Genetics
Baylor College of Medicine
One Baylor Plaza, MS BCM225
Houston, TX, 77030, U.S.A.