Optogenetic dissection of NF-kB function in controlling macrophage behaviour during tissue regeneration. (360G-Wellcome-108111_Z_15_Z)

Transcription factor Nuclear Factor (NF)-kB is a critical regulator of macrophages and is implicated in several chronic diseases affecting muscle. Macrophages migrate into injured muscle during regeneration; this coincides with NF-kB activation in many cell types, but how NF-kB controls macrophage behaviour in this context is not understood. Based on our characterisation of muscle regeneration in zebrafish, we propose that NF-kB activity directs macrophage migration and that this is important fo r effective regeneration. This proposal therefore aims to determine how NF-kB signalling regulates macrophage responses to muscle injury in vivo. A combination of advanced genetic and optical techniques will be employed in the zebrafish to manipulate NF-kB activity and show how this affects macrophage cell behaviour in the context of tissue regeneration. To achieve this we will build a novel optogenetic system for rapidly activating NF-kB in a highly localised manner. This will permit direct v isualisation of macrophage cell responses to activation of NF-kB. Specific goals for this project are: 1. show if macrophage migration to wound sites requires NF-kB signalling. 2. develop a light-controlled optogenetic system for control of NF-kB activity in individual cells. 3. show if macrophage behaviour is affected by optogenetic activation of NF-kB signalling.