Research in the laboratory investigates the molecular genetic basis of morphological evolution. We're interested in how both nature and nurture affect final adult morphology. We use a variety of approaches including genetics, genomics and developmental biology.
Our study system is the pea aphid. Aphids are remarkable insects, able to produce a variety of morphologies across their complex life cycles that alternate between asexual and sexual development. During the asexual phase, females are often wingless and specialize in the mass production of genetically identical wingless daughters. However, if their host plant becomes too crowded, those same females can switch to producing daughters that have wings as adults so that those daughters can fly away and find better food sources. Thus, winged and wingless females of pea aphids are genetically identical yet morphologically very different. How these alternative morphologies are produced is one of the main questions we address in the lab.
During their sexual phase in the fall, pea aphids produce winged and wingless males as well. However, unlike the females the males are not genetically identical and their morphology is not determined by environmental circumstances. Rather, adult male morphology appears to be under the control of a single locus on the X chromosome called aphicarus. A main research interest in the lab addresses identifying the aphicarus locus and figuring out how it acts.
Ongoing projects in the lab include:
1. Genetic mapping of the aphicarus locus in collaboration with David Stern;
2. Developmental investigations into wing formation and/or degeneration in the winged and wingless morphs;
3.Transcriptomic and proteomic approaches to understanding the molecular basis of wing morph induction in females;
4. The role of DNA methylation in the female polyphenism.
- Vellichirammal, N. N., Gupta, P., Hall, P., and J. A. Brisson. 2017. Ecdysone signaling underlies the pea aphid transgenerational wing polyphenism. Proc. Nat. Acad. Sciences. doi:10.1073/pnas.1617640114.
- Grantham, M. E., Antonio, C. J., O’Neil, B. R., Zhan, Y. X., and J. A. Brisson. 2016. A case for a joint strategy of diversified bet hedging and plasticity in the pea aphid wing polyphenism. Biol. Letters 12:20160654.
- Vellichirammal, N. N., Madayiputhiya, N., and J. A. Brisson. 2016. The genome-wide transcriptional response underlying the pea aphid wing polyphenism. Mol. Ecol. 25:4146-4160.
- Brisson, J. A., and G. K. Davis. 2016. The right tools for the job: Regulating polyphenic morph development in insects. Curr. Op. Insect Science 13:1-6.
- Zera, A. J., and J. A. Brisson. 2015. Evolutionary and ecological physiology of polyphenism: Integrating proximate and ultimate mechanisms. In: Integrative Organismal Biology. Eds: Martin, L. B., Ghalambor, C. K., and A. Woods. Oxford University Press.
- Purandare, S., Bickel, R. D., Jaquiery, J., Rispe, C., and J. A. Brisson. 2014. Accelerated evolution of morph-biased genes in pea aphids. Mol. Biol. Evol. 31: 2073-2083.
- Bickel, R. D., Dunham, J. P., and J. A. Brisson. 2013. Widespread selection across coding and noncoding DNA in the pea aphid genome. G3: GENES, GENOMES, GENETICS. 3: 993-1001.