Sudip Paudel

High-throughput spatiotemporal measurements of cellular attributes in vivo, such as calcium (Ca2+) activity at the single-cell level, are essential for understanding of the underlying dynamics of embryonic development. However, it is a challenge to obtain these measurements from a tissue type such as early neural tissue, where cells are undergoing ongoing division, intercalation, and migration. Moreover, Ca2+ activity is multidimensional; it occurs in many different forms including spikes and waves and at different amplitudes, frequencies, and locations, parameters that are important for neural development. However, unlike Ca2+ spikes of mature neurons, spatiotemporal patterns of the seemingly stochastic spiking that occurs in the developing vertebrate nervous system remain poorly understood. It remains unknown whether there is a stereotypical spiking pattern in embryos at a given stage of development or whether the activity is truly stochastic. This is largely due to the lack of an appropriate and comprehensive analysis technique. In this study, we aim to analyze spatiotemporal pattern of spikes of presynaptic neurons in the neural plate of Xenopus laevis. Our preliminary analysis of the Xenopus neural plate using a genetically encoded Ca2+ marker (GCaMP6) suggest that while Ca2+ waves occur in a conserved pattern, spiking activity appears to be stochastic. Our approach of digitally creating a composite neural plate from many embryos, in general, can be applied to conduct spatiotemporal analyses of various cellular attributes that require imaging disparate tissue regions.

Sudip Paudel is a fifth-year Ph.D. candidate in the Applied Science Department at William & Mary. His research area includes understanding underlying molecular mechanism(s) of early neural development. The development of central nervous system is orchestrated by a complex network of transcription factors and signaling molecules, including calcium. For his Ph.D. dissertation, he is studying spatiotemporal pattern of calcium spikes during early neural development.