RT Journal Article
SR Electronic
T1 Quantitative live-cell imaging yields novel insight into endogenous WNT/CTNNB1 signaling dynamics
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.05.28.120543
DO 10.1101/2020.05.28.120543
A1 S.M.A. de Man
A1 G. Zwanenburg
A1 M.A. Hink
A1 R. van Amerongen
YR 2020
UL http://biorxiv.org/content/early/2020/05/28/2020.05.28.120543.abstract
AB WNT/CTNNB1 signaling regulates tissue development and homeostasis in all multicellular animals. Multiple aspects of the underlying molecular mechanism remain poorly understood and critical information on endogenous WNT/CTNNB1 signaling dynamics is missing. Here we combine CRISPR/Cas9-mediated genome editing and quantitative live-cell microscopy to measure diffusion characteristics of fluorescently tagged, endogenous CTNNB1 in human cells with high spatiotemporal resolution. State-of-the-art functional imaging reveals that both in the absence and presence of WNT, a substantial fraction of CTNNB1 resides in slow-diffusing complexes in the cytoplasm and that WNT stimulation changes their identity. We also measure the concentration of complexed and free CTNNB1 in both the cytoplasm and the nucleus before and after WNT stimulation, and use these parameters to build a minimal computational model of WNT/CTNNB1 signaling. Our work reveals that WNT regulates the dynamic distribution of CTNNB1 across different functional pools by modulating the destruction complex, nucleocytoplasmic shuttling and nuclear retention.Competing Interest StatementThe authors have declared no competing interest.