Optogenetics allow scientists to control the activity of specific neurons and study their downstream influence on a variety of biological processes, including behavior. In rodent studies this technique requires optical fiber implantation, but as they are transparent, fiber optics are not needed in studies with zebrafish larvae. Light simply needs to shine in the right direction, making it easy to study the role of specific neurons in behavior.
By inserting light-sensitive receptor proteins into neurons in vivo, scientists are able to make these neurons sensitive to activation by light of specific wavelengths.
In zebrafish studies, the light-sensitive receptor protein halorhodopsin (NpHR) has successfully been used to inhibit swimming behavior in zebrafish larvae (Arrenberg, et al., 2009). Other research showed that channelrhodopsin-2 (ChR2) activation induced backward swimming in a sparse transgene expression line (Zhu et al., 2009).
Application of optogenetic stimulation in zebrafish larvae does not require fiber optics, but it does require the correct wavelength (color) of light. When using the DanioVision Observation Chamber, the Optogenetics Add-on provides a way to accurately control and precisely time the application of optogenetic stimulation to up to 96 individuals simultaneously (working with 96 well plates).
Interested in DanioVision? Read more about it here.