Melissa Rolls
Assistant Professor of Biochemistry and Molecular Biology
118 Life Science BuildingUniversity Park, PA 16802
Research Interests
Subcellular compartmentalization of neurons
Research Summary
The Rolls lab uses live imaging and Drosophila genetics to investigate two broad areas of neuronal cell biology:
1. neuron polarity, focusing on microtubule polarity
2. neuronal responses to injury including degeneration and regeneration.
Microtubule polarity:
Neurons receive information from dendrites and send information through axons, each neuron thus has two major functionally and molecularly distinct compartments. We have found that microtubules in these two compartments have opposite orientation in all types of Drosophila neurons. This opposite polarity likely underlies many differences between axons and dendrites, so we are working to identify mechanisms that allow a single cell to set up two different arrangements of microtubules.
Neuronal responses to injury:
Many neurons must remain intact for an animal’s entire life. In order to do this, they must be able to recover from injury. Two aspects of this recovery are degeneration of regions too damaged to be repaired and regeneration of regions required for function. We study several types of degeneration and regeneration at the single cell level in whole intact animals and aim to identify molecular mechanisms that control the morphological changes we track.
Figure 1: An example of controlled in vivo neuron injury. Using a pulsed UV laser we can sever single axons in whole animals. Neuronal microtubules are labeled with GFP and glial membranes are labeled with RFP.
Figure 2: Severing axons close to the cell body elicits regeneration of an axon from a dendrites. The cell is labeled with RFP, and was injured and tracked over several days in whole intact animals. In this cell new growth can be seen emerging from the dendrite on the right.
Representative Publications
- Tao, J. Rolls, M.M. Dendrites have a rapid program of injury-induced degeneration that is molecularly distinct from developmental pruning. Journal of Neuroscience in press.
- Mattie, F.J., Stackpole, M.M., Stone, M.C., Clippard, J.R., Rudnick, D.A., Qiu, Y., Tao, J., Allender, D.L., Parmar, M. Rolls, M.M. (2010) Directed microtubule growth, +TIPs and kinesin-2 are required for uniform microtubule polarity in dendites. Current Biology 21:2169-77.
- Stone, M. C., Nguyen, M. M., Tao, J., Allender, D. L., Rolls, M. M. (2010) Global upregulation of microtubule dynamics and polarity reversal during regeneration of an axon from a dendrite. Molecular Biology of the Cell 21: 767-77.
- Minn, I., Rolls, M. M., Hanna-Rose, W., Malone, C. J. (2009) SUN-1 and ZYG-12, mediators of centrosome-nucleus attachment, are a functional SUN-KASH pair in Caenorhabditis elegans. Molecular Biology of the Cell 20: 4586-95.
- Zhou, K., Rolls, M. M., Hall, D. H., Malone, C. J., Hanna-Rose, W. (2009) A ZYG-12-dynein interaction at the nucelar envelope defines cytoskeletal architecture in the C. elegans gonad. Journal of Cell Biology 186: 229-241.
- Stone, M. C., Roegiers, F., Rolls, M. M. (2008) Microtubules have opposite orientation in axons and dendrites of Drosophila neurons. Molecular Biology of the Cell 19: 4122-4129.
- Satoh, D., Sato, D., Tsuyama, T., Saito, M., Ohkura, H., Rolls, M., Ishikawa, F., Uemura, T. (2008)
- Spatial control of branching within dendritic arbors by dynein-dependent transport of Rab5 endosomes. Nature Cell Biology 10: 1164-1171.
- Rolls, M. M., Satoh, D. Clyne, P. J., Henner, A. L., Uemura, T, Doe, C. Q. (2007) Polarity and intracellular compartmentalization of Drosophila neurons. Neural Development 2:7 (1-14).
