Alexander F. Schier, PhD
Harvard Medical School
The Schier lab seeks to understand the molecular basis of embryogenesis, and to identify the genes and circuits that regulate sleep and wakefulness.
We mainly use zebrafish as a model system, because genetic and imaging approaches can be combined to study complex behaviors and developmental processes in a vertebrate.
The vertebrate body plan is set up during gastrulation, when a ball of undifferentiated, totipotent cells is transformed into an embryo. This process results in the formation of the three germ layers (ectoderm, mesoderm, and endoderm) and the three axes (anterior-posterior, dorsal-ventral and left-right). We wish to understand how signaling pathways, transcription factors, chromatin modifications and non-coding RNAs regulate this process. We are using genetic, biophysical and in vivo imaging approaches to determine how signals move through fields of cells and elicit concentration dependent effects. In parallel, we use biochemical and genetic approaches to determine how chromatin modifications and non-coding RNAs regulate early development.
Sleep and wakefulness
The genetic and cellular mechanisms that control sleep and wake states remain largely elusive. We have established zebrafish as a model system for sleep research. Zebrafish have the basic hallmarks of sleep-like behaviors. Sleeping fish require stronger stimuli than awake fish to initiate movement and sleep deprivation is followed by increased sleep. In addition, the zebrafish brain expresses peptides that have been implicated in human sleep disorders. We are using genetic and pharmacological screens to isolate sleep regulators and use electrophysiological and imaging approaches to dissect sleep circuits.