bioRxiv preprint doi: https://doi.org/10.1101/137059; this version posted July 26, 2017. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC 4.0 International license. Improved Split Fluorescent Proteins for Endogenous Protein Labeling Siyu Feng1, Sayaka Sekine2, Veronica Pessino3, Han Li4, Manuel D. Leonetti4, Bo Huang2, 5, 6 * 1The UC Berkeley-UCSF Graduate Program in Bioengineering, San Francisco, CA 94143 USA; 2Department of Pharmaceutical Chemistry, University of California in San Francisco, San Francisco, CA 94143, USA; 3Graduate Program of Biophysics, University of California, San Francisco, San Francisco, CA 94143, USA; 4Department of Cellular and Molecular Pharmacology, and Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94143, USA; 5Department Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143, USA. 6Chan Zuckerberg Biohub, San Francisco, CA 94158, USA * Correspondence should be addressed to
[email protected]. bioRxiv preprint doi: https://doi.org/10.1101/137059; this version posted July 26, 2017. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC 4.0 International license. ABSTRACT Self-complementing split fluorescent proteins (FPs) have been widely used for protein labeling, visualization of subcellular protein localization, and detection of cell-cell contact. To expand this toolset, we have developed a screening strategy for the direct engineering of self-complementing split FPs.