A composition-dependent molecular clutch between T cell signaling condensates and actin
- Marine Biological Laboratory, United States
- University of Texas Southwestern Medical Center, United States
Abstract
During T cell activation, biomolecular condensates form at the immunological synapse (IS) through multivalency-driven phase separation of LAT, Grb2, Sos1, SLP-76, Nck, and WASP. These condensates move radially at the IS, traversing successive radially-oriented and concentric actin networks. To understand this movement, we biochemically reconstituted LAT condensates with actomyosin filaments. We found that basic regions of Nck and N-WASP/WASP promote association and co-movement of LAT condensates with actin, indicating conversion of weak individual affinities to high collective affinity upon phase separation. Condensates lacking these components were propelled differently, without strong actin adhesion. In cells, LAT condensates lost Nck as radial actin transitioned to the concentric network, and engineered condensates constitutively binding actin moved aberrantly. Our data show that Nck and WASP form a clutch between LAT condensates and actin in vitro and suggest that compositional changes may enable condensate movement by distinct actin networks in different regions of the IS.
Data availability
Data are available in the BioStudies database (http://www.ebi.ac.uk/biostudies) under accession number S-BIAD6. Image data are available in the Image Data Resource (IDR) (https://idr.openmicroscopy.org) under accession number idr0055. Condensate analysis code is available on GitHub at https://github.com/kjaqaman/CondensateAnalysis. Colocalization analysis code is available on GitHub at https://github.com/kjaqaman/ColocPt2Cont. Cluster tracking analysis code is available on GitHub at https://github.com/DanuserLab/u-track. Polarization microscopy analysis code is available on GitHub at https://github.com/mattersoflight/Instantaneous-PolScope.
Article and author information
Author details
Darius Vasco Köster
Funding
Howard Hughes Medical Institute
- Ronald D Vale
- Michael K Rosen
Cancer Research Institute
- Xiaolei Su
National Institutes of Health (R35 GM119619)
- Khuloud Jaqaman
National Institutes of Health (F32 DK101188)
- Jonathon A Ditlev
Welch Foundation (I-1544)
- Michael K Rosen
Department of Science and Technology, Government of India (J C Bose Fellowship)
- Satyajit Mayor
Margadarshi Fellowship from the Wellcome Trust - Department of Biotechnology, India Alliance (IA/M/15/1/502018)
- Satyajit Mayor
National Institutes of Health (R01 GM100160)
- Tomomi Tani
UT Southwestern Endowed Scholars Program
- Khuloud Jaqaman
National Research Service Award F32 (F32 DK101188)
- Jonathon A Ditlev
CPRIT Training Grant (RP140110 PI: Michael White)
- Anthony R Vega
AXA Research Fund and the National Centre for Biological Sciences, Tata Institute for Fundamental Research
- Darius Vasco Köster
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Ditlev et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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A composition-dependent molecular clutch between T cell signaling condensates and actin
eLife 8:e42695.
https://doi.org/10.7554/eLife.42695
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