Neurons are complex cells most of which consist of a network of dendrites and a single branched axon. Because these processes can be extremely long, cells have evolved an efficient method to transport nuclear products to various parts of the cell using the microtubule based motors kinesin and dynein. The regulation of this transport is a complicated process involving microtubule associated proteins and posttranslational modifications of tubulin and defects in these factors can lead to several debilitating disorders such as Alzheimer’s disease, dementias, and parkinsonisms. The Berger lab uses a combination of state of the art biochemical, biophysical, and cell biology techniques to investigate microtubule based transport in the neuron. Currently we are exploring how the microtubule associated protein tau acts in concert with posttranslational modifications of tubulin to direct kinesin mediated transport in the neuron. By using a combination of fluorescence techniques, single molecule analysis, kinetic approaches, and microscopy we hope to combine current in vitro and in vivo knowledge into a working model for microtubule based transport in the neuron. We are also applying these techniques to explore the function of the actin based molecular motor myosin.