Genome-wide YFP Fluorescence Complementation Screen Identifies New Regulators for Telomere Signaling in Human Cells

Severance Hospital Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University Health System, Seoul, Korea.
Molecular &amp Cellular Proteomics (Impact Factor: 6.56). 11/2010; 10(2):M110.001628. DOI: 10.1074/mcp.M110.001628
Source: PubMed


Detection of low-affinity or transient interactions can be a bottleneck in our understanding of signaling networks. To address this problem, we developed an arrayed screening strategy based on protein complementation to systematically investigate protein-protein interactions in live human cells, and performed a large-scale screen for regulators of telomeres. Maintenance of vertebrate telomeres requires the concerted action of members of the Telomere Interactome, built upon the six core telomeric proteins TRF1, TRF2, RAP1, TIN2, TPP1, and POT1. Of the ∼12,000 human proteins examined, we identified over 300 proteins that associated with the six core telomeric proteins. The majority of the identified proteins have not been previously linked to telomere biology, including regulators of post-translational modifications such as protein kinases and ubiquitin E3 ligases. Results from this study shed light on the molecular niche that is fundamental to telomere regulation in humans, and provide a valuable tool to investigate signaling pathways in mammalian cells.

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Available from: Dong Yang, May 14, 2014
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    • "All tested BiFC-positive TFs were found by co-ip (Supplementary file 3), highlighting that the S2 cell environment is appropriate for revealing interactions with tissue-specific TFs. Thus, observations from BiFC could be reproduced by co-ip, as previously noticed (Lee et al., 2011). Co-ip was also performed with the three positive competitors that did not produce BiFC with AbdA (Kr, Lmd, Pan). "
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    eLife Sciences 04/2015; 4(4). DOI:10.7554/eLife.06034 · 9.32 Impact Factor
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    • "Bi - molecular fluorescence complementation assay Pair - wise examination of protein – protein interactions by BiFC was carried out as previously described ( Lee et al . , 2011 ) . HTC75 cells stably co - expressing two proteins respectively tagged with YFP fragments ( YFPn and YFPc ) were generated for fluorescence complementation assessment in live cells by flow cytometry ."
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    Journal of Cell Science 11/2014; 128(2). DOI:10.1242/jcs.159467 · 5.43 Impact Factor
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    • "Akt regulates telomere protection, X. Han et al. 1097 ª 2013 the Anatomical Society and John Wiley & Sons Ltd Cells expressing protein pairs respectively tagged with YFPc (residues 156–239 of YFP) and YFPn (residues 1–155 of Venus YFP) were analyzed by flow cytometry as previously described (Lee et al., 2011). 293T cells were used for transient expression and retroviral packaging. "
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