Boston University Department of Biology

Faculty Profiles

Current Research

My main research focus is on the biophysical events underlying transmitter release. Neurotransmitter secretion involves ion channel gating, diffusion and buffering of calcium ions, vesicular fusion as well as the mobilization and recycling of, synaptic vesicles. We use electrophysiological and imaging techniques to monitor processes underlying synaptic transmission at a high time resolution. Using the crayfish neuromuscular junction, we perform simultaneous pre- and post-synaptic recordings or voltage clamp to analyze the kinetics of transmitter release under control and facilitated conditions, and calcium sensitive dyes to monitor the dynamics of presynaptic calcium ion diffusion and buffering. We are currently focusing on mechanisms regulating the probability of transmitter release by comparing two classes of active zone residing in the same varicosity but with different release probabilities. Finally, since detailed events during the course of synaptic transmission happen at a sub-millisecond time scale and with nanometer spatial resolution, both of which are beyond the capability of current experimental techniques, we are using a mathematical modeling approach to gain insights to the behavior of calcium ions with sufficient resolution.

In addition to events occurring around the active zones, we also study the excitability of axonal branches to gain insights into the interaction between axonal excitability and transmitter release. We use voltage sensitive dyes to investigate action potentials and subthreshold activities in fine axonal branches. This line of research is unique in that very few preparations allow measurement of membrane potential within such fine structures and at such a high time resolution. We are currently investigating how presynaptic inhibition changes the amplitude and duration of action potentials at fine branches and terminals.

Courses Taught

• BI 325 Principles of Neuroscience
• BI 445/645 Cellular and molecular neurophysiology
• BI 575 Techniques in cellular and molecular neuroscience

Selected Publications

• J.-W. Lin (2008). Electrophysiological events recorded at presynaptic terminals of the crayfish neuromuscular junction with a voltage indicator J. Physiology 586: 4935-4950.
• Allana T, Lin J -W. (2008). Effects of increasing Ca2+ channel-vesicle separation on facilitation at the crayfish inhibitory neuromuscular junction. Neuroscience, 1242-54.
• Lin J -W, Fu Q, Allana T. (2005). Probing the endogenous Ca2+ buffers at the presynaptic terminals of the crayfish neuromuscular junction. J. Neurophysiol. 94, 377-386.
• Allana TN, Lin J -W. (2004). Relative distribution of Ca2+ channels at the crayfish inhibitory neuromuscular junction. J Neurophysiol. 92, 1491-1500.
• Lin J –W, Faber DS. (2002). Modulation of synaptic delay during synaptic plasticity. Trends in Neurosciences, 25, 449-455.
• Vyshedskiy A, Allana T, Lin J -W. (2000). Analysis of presynaptic Ca2+ influx and transmitter release kinetics during facilitation at the inhibitor of the crayfish neuromuscular junction. J. Neuroscience 20, 6326-6332.
• Vyshedskiy A, Delaney K, Lin J -W. (1998). Neuromodulators enhance transmitter release by two separate mechanisms at the inhibitor of crayfish opener muscle. J. Neuroscience 18, 5160-5169.
• Vyshedskiy A, Lin J -W. (1997). A change of transmitter release kinetics during facilitation revealed by prolonged test pulses at the inhibitory synapse of the crayfish opener muscle. Journal of Neurophysiology 78, 1791-1799.