Stocks carrying split-GFP and other split-fluor components can be found here. 

Split-fluors are being developed for a variety of uses, including 1) assessing the proximity of cellular membranes , 2) GRASP (GFP Reconstitution Across Synaptic Partners) in which non-functional split-GFP proteins expressed on the extracellular membrane of different neurons can reconstitute a functional fluorescent protein in places where the two membranes are in contact and 3) studying protein expression and localization by endogenously tagging a protein with one split component and visualizing only in cells where the two components of the split-fluor are co-expressed.

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