PT  - JOURNAL ARTICLE
AU  - Anita Kumari
AU  - Pablo J. Sáez
AU  - Mathieu Maurin
AU  - Danielle Lankar
AU  - Mabel San Roman
AU  - Raphael Voituriez
AU  - Katharina Hennig
AU  - Vanessa F. Boura
AU  - Mikael C.I. Karlsson
AU  - Martial Balland
AU  - Ana-Maria Lennon Dumenil
AU  - Paolo Pierobon
TI  - Actomyosin-driven force patterning controls endocytosis at the immune synapse
AID  - 10.1101/452896
DP  - 2018 Jan 01
TA  - bioRxiv
PG  - 452896
4099  - http://biorxiv.org/content/early/2018/10/25/452896.short
4100  - http://biorxiv.org/content/early/2018/10/25/452896.full
AB  - An important channel of cell-to-cell communication is direct contact. The immune synapse is a paradigmatic example of such type of interaction: it forms upon engagement of antigen receptors in lymphocytes by antigen-presenting cells and allows the local exchange of molecules [1]. Although [2], how forces organize and mechanics has been shown to play an important role in this process impact on synapse function is unknown. We found that mechanical forces are spatio-temporally patterned at the immune synapse: global contractile forces are observed at the synapse periphery and local point-like forces are detected at its centre. The global contractile forces result from a pulsatile centripetal actomyosin flow that leads to formation of F-actin protrusions from which the central point like forces emerge. Noticeably, these force-producing actin protrusions constitute the main site of antigen extraction and endocytosis. Accordingly, deletion of the myosin IIA gene leads to impaired B cell responses. The interplay between global and local forces governed by the actomyosin cytoskeleton therefore controls the endocytic function of the immune synapse and might constitute a more general mechanism in the physical regulation of cell-cell interactions.