BOOPTHAT: An inexpensive and scalable system for spatiotemporal activation of heat-shock transgenes in zebrafish

Background: Gaining finer spatiotemporal control over gene expression is critical for unraveling the regulatory networks that coordinate embryogenesis. While the heat-shock inducible gene expression system is a widely used tool for controlling temporal transgene expression, its applicability in spatiotemporal control is limited. Results: We present the BOOPTHAT (Batch-Operating Optically Powered Targeted Heater for Activating Transgenes) as a low-cost system for activating heat-shock inducible transgenes with spatiotemporal control in multiple zebrafish embryos at a time. The BOOPTHAT system is built from 3D printed components and inexpensive consumer parts. Independent 3D printed micromanipulators are used to position optical fiber probes. When coupled to a light source, the probes are heated photothermally and are used to perform targeted gene activation in multiple samples at a time. Conclusions: By adding a level of spatial control onto the well-established system of heat-shock inducible transgenes, we take advantage of the existing infrastructure surrounding the heat-shock induction system and introduce new ways to use the multitude of existing lines. We demonstrate the capabilities of our system and highlight some areas of research that stand to benefit from this frugal and effective system.