 Hi, I'm Chris Beistroff, corresponding author on quantitative in vivo solubility and reconstitution of Truncated Circular Permutants of Green Fluorescent Protein by Wang Nye and Beistroff. We present Leave One Out Green Fluorescent Protein, which we will call LuGFP. Green Fluorescent Protein can be split into two parts, and the parts sometimes reassemble to reconstitute fluorescence, which is lost when a part has been left out. This has been done previously by Jeffrey Waldo by removing the last beta strand at the 11-stranded barrel, and also by us, when we permuted the sequence and removed strand 7, and also by Stephen Boxer, who removed the central helix and added it back. In this work, we exhaustively removed each of the 11-beta strands and the central helix from the GFP sequence, one at a time, of course. And we then measured the solubility in bacteria by gel densitometry, and also by co-expressing each LuGFP with its left out segment, we measured the ability of the LuGFPs to bind their missing piece and glow. Both solubility and fluorescence experiments were done in triplicate with proper controls and were shown to be very reproducible in our hands. What we found is that the solubility of the LuGFP depends very much on which part was left out. If strands 1 through 3 were left out, then the molecule was insoluble, and adding back the missing peptide did not rescue fluorescence. If we removed the central helix or strand 5, then the molecule was soluble, but fluorescence could not be reconstituted by adding back the missing peptide. But if strands 4, 6, 7, 8, 9, 10, or 11 was left out, then the molecule was partially soluble and adding back the peptide reconstituted fluorescence. In vivo solubility is traditionally thought of as a measure of the folding efficiency. If a protein folds efficiently, it is soluble, otherwise it aggregates in the unfolded state. Here we see different degrees of solubility depending on what part was left out, suggesting that folding is not an all or none process, and when some parts are left out of the molecule, the molecule can fold while leaving out other parts, prevents folding. We may hypothesize that the parts that don't matter as much for folding efficiency fold late in the folding pathway, while parts that lead to the most aggregation fold early. If so, strands 1 through 3 represent the folding nucleation side of TFP, while strands 7 through 9 fold last. Thank you for listening.