THOMAS A. SCHIKORSKI, Ph.D.

Assistant Professor

Department of Anatomy and Neurobiology

The University of Tennessee College of Medicine

Address

The University of Tennessee Health Science Center

855 Monroe Avenue, Suite 515

Memphis, TN 38163

Tel: (901) 448-1358; Fax: (901) 448-7193;

Lab: 318 Wittenborg Anatomy Building

Education

Ph.D. Institution: Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany

Postdoctoral: Howard Hughes Medical Institute at The Salk Institute, La Jolla, CA

Research Interests

The work in my laboratory focuses on synaptic transmission at central synapses. Two main topics are under investigation: The structural basis of synaptic plasticity and the synaptic vesicle cycle.

1. Synaptic plasticity.

Synaptic strength can be dynamically adjusted, which serves a number of neuronal functions.

1. Balancing the synaptic input across a dendritic tree to compensate for the electronic distance to the spike initiation zone.
2. Homeostatic synaptic scaling, which matches the dynamic range of the synaptic input to the dynamic range of the axonal output.
3. Activity-dependent changes in synaptic efficacy, like long-term potentiation. These mechanisms are believed to be the cellular mechanism for learning and memory.

By using cell culture and brain slices, the molecular mechanisms and the structural basis for the different forms of synaptic plasticity are studied. Interdisciplinary approaches combining electrophysiology, functional imaging, electron microscopy, and modern molecular genetic methods are exploited.

2. The synaptic vesicle cycle.

Synaptic vesicles fuse with the plasma membrane in order to release neurotransmitter. After release synaptic vesicles are being retrieved from the plasma membrane, however, the underlying mechanisms for membrane retrieval are not well understood and hotly debated. Furthermore, the pathway retrieved vesicles take until they again become release-competent are not known. An electron microscopic approach, which can track retrieved vesicles, is used to discover these mechanisms and their molecular constituents. The approach is complemented with modern imaging techniques and molecular genetic techniques.

Recent Publications

• Qu L, Hu Y, and Schikorski T (2008) Quantitative analysis of associational/commissural excitatory synapses of the hippocampal CA3 region. J. Comp Neurol. Submitted.
• Qu L, Akbergenova Y, Hu Y, and Schikorski T (2008) Synaptic vesicle size revisited. J. Comp. Neruol. Submitted.
• Hu Y, Qu L, and Schikorski T (2008) Mean synaptic vesicle size varies among individual excitatory hippocampal synapses. Synapse. In Press.
• Schikorski T, Young SM Jr, Hu Y. Horseradish peroxidase cDNA as a marker for electron microscopy in neurons. J Neurosci Methods. 2007 Sep 30;165(2):210-5. Epub 2007 Jun 12. PMID: 17631969
• Chklovskii DB, Schikorski T, Stevens CF. Wiring optimization in cortical circuits. Neuron. 2002 Apr 25;34(3):341-7. PMID: 11988166
• Murthy VN, Schikorski T, Stevens CF, Zhu Y. Inactivity produces increases in neurotransmitter release and synapse size. Neuron. 2001 Nov 20;32(4):673-82. PMID: 11719207

view complete list of references (pubmed link)