Development of a Tool to Visualize F-actin and Organelle Contact Sites

The actin cytoskeleton plays a critical role in not only cell shape and motility, but also organelle function. Growing evidence reveals the importance of actin dynamics at organelle membranes in mediating cellular processes and homeostasis. An understanding of the nature and relevance of these interactions would provide valuable information on cellular mechanisms but is limited by the availability of tools to identify and characterize contacts. This work presents a versatile tool based on the FAST (Fluorescence-Activating and Absorption-Shifting Tag) reporter system to visualize the dynamic contacts between F-actin and mitochondria and can be further adapted for the visualization of other cytoskeleton-organelle as well as interorganelle contacts.