Share Email Print

Proceedings Paper

Characterizing the interactions between prolyl isomerase pin1 and phosphatase inhibitor-2 in living cells with FRET and FCS
Author(s): Yuansheng Sun; Lifu Wang; Vinod Jyothikumar; David L. Brautigan; Ammasi Periasamy
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Phosphatase inhibitor-2 (I2) was discovered as a regulator of protein Ser/Thr phosphatase-1 and is conserved from yeast to human. Binding between purified recombinant I2 from different species and the prolyl isomerase Pin1 has been demonstrated with pull-down assays, size exclusion chromatography and nuclear magnetic resonance spectroscopy. Despite this, questions persist as to whether these proteins associate together in living cells. In this study, we prepared fluorescent protein (FP) fusions of I2 and Pin1 and employed both Förster Resonance Energy Transfer (FRET) and Fluorescence Correlation Spectroscopy (FCS) imaging techniques to characterize their interactions in living cells. In both intensity-based and time-resolved FRET studies, we observed FRET uniformly across whole cells co-expressing I2-Cerulean and Pin1-Venus that was significantly higher than in negative controls expressing Cerulean FP (without fusing to I2) as the FRET donor and Pin1-Venus, showing a specific interaction between I2-Cerulean and Pin1-Venus in living cells. We also observed the co-diffusion of I2-Cerulean and Pin1-mCherry in Fluorescence Cross Correlation Spectroscopy (FCCS) measurements. We further showed that I2 itself as well as I2-Pin1 formed complexes in living cells (predicted from in vitro studies) via a quantitative FRET assay, and demonstrated from FCS measurements that both I2 and Pin1 (fused to Cerulean) are highly mobile in living cells.

Paper Details

Date Published: 9 February 2012
PDF: 9 pages
Proc. SPIE 8226, Multiphoton Microscopy in the Biomedical Sciences XII, 82263T (9 February 2012); doi: 10.1117/12.915315
Show Author Affiliations
Yuansheng Sun, W.M. Keck Ctr. for Cellular Imaging, Univ. of Virginia (United States)
Lifu Wang, Univ. of Virginia (United States)
Vinod Jyothikumar, W.M. Keck Ctr. for Cellular Imaging, Univ. of Virginia (United States)
David L. Brautigan, Univ. of Virginia (United States)
Ammasi Periasamy, W.M. Keck Ctr. for Cellular Imaging, Univ. of Virginia (United States)

Published in SPIE Proceedings Vol. 8226:
Multiphoton Microscopy in the Biomedical Sciences XII
Karsten König, Editor(s)

© SPIE. Terms of Use
Back to Top