Kari Naylor, Ph.D.
Ph.D., Microbiology, University of California, Davis, 2004
Started at UCA in 2006
Advanced Cell Biology
The overall goal of my research is to understand the molecular mechanism of mitochondrial dynamics (fission, fusion, and motility). Why is this important? Mitochondria are the powerhouse of the cell. They convert biomolecules into energy sources that cells can use to power cellular and organismal function. To do this, mitochondria must have a specific structure; alteration of this structure changes the ability of the mitochondria to function. It has been well established that determining factors of mitochondrial structure are the processes of fission (division of the mitochondria), fusion (joining of two mitochondria), and movement within the cell. When these processes are disrupted mitochondrial structure is altered and significant functional defects arise. For example, loss of fission causes significant developmental delays in many organisms, including humans. To date, only one individual with a fission defect has been identified. The result was severe developmental disabilities and death a few days after birth. Defects in fusion can result in childhood blindness or Charcot-Marie Tooth, a disease that manifests as muscle atrophy in the hands and feet. Defects in both processes alter the regulation of apoptosis, a process critical for maintaining healthy cells. Finally, the latest research suggests that fission and fusion may be involved in the progression of Alzheimer’s and Parkinson’s disease. To understand these processes and their role in human disease I have a variety of projects centered on the Mitochondrial Dynamics Model that I have established in Dictyostelium discoideum (Schimmel et al., 2012). Upon establishing that D. discoideum have these processes, we have been trying to understand the regulation of mitochondrial dynamics by identifying key factors. So far we have established that the cytoskeleton, both actin and microtubules, plays a significant role (Woods et al., 2016) and these processes are diminished prior to the degeneration of neurons (Berbusse et al., 2016). We are currently trying to determine the role of a variety of proteins that are predicted to mediate fission and fusion, including proteins that are homologous to bacterial division proteins (FszA and FszB) and homologous to dynamins – master regulators of mitochondrial dynamics in yeast and mammalian cells (DlpA, DlpB, DlpC). Finally, we have begun to develop a model for Parkinson’s disease using D. discoideum. We are in the early stages of this project, but are currently attempting to mimic cellular phenotypes found in cells affected by Parkinson’s, such as increased ROS, decreased ATP production, and altered cytoskeleton structure.
Berbusse, G*., Woods, L.*, Bhupinder, V. P., Naylor K. (2016). Mitochondrial Dynamics Decrease Prior to Axon Degeneration Induced by Vincristine and are Partially Rescued by Overexpressed cytNmnat1. Frontiers in Cellular Neuroscience, 10, 8. http://journal.frontiersin.org/article/10.3389/fncel.2016.00179/full
Woods, L.*, Berbusse, G.*., Naylor K. (2016). Microtubules Are Essential for Mitochondrial Dynamics–Fission, Fusion, and Motility–in Dictyostelium discoideum. Frontiers: Cell and Developmental Biology, 4, 9. http://journal.frontiersin.org/article/10.3389/fcell.2016.00019/full#
Schimmel, BG; Berbusse, GW; and Naylor, K. Mitochondrial fission and fusion in Dictyostelium discoideum: a search for proteins involved in membrane dynamics. BMC Res Notes. 5:505, 2012 PMID: 22980139
Gray R, Gray A, Fite J, Jordan R, Stark S, Naylor K. A simple microscopy assay to teach the processes of phagocytosis and exocytosis. CBE-LSE. 11(2):180-186, 2012. PMID: 22665590