A new article entitled Formation of polarized contractile interfaces by self-organized Toll-8/Cirl GPCR asymmetry has recently been published in Developmental Cell. This article is the result of a collaboration between the AMU, CNRS, IBDM and Inserm.
Entitlted “Formation of polarized contractile interfaces by self-organized Toll-8/Cirl GPCR asymmetry“, this article in Developmental Cell (June 10, 2021) is the result of a collaboration between 2 of our partner institute: IBDM and Inserm and AMU. The article is signed by 7 of our CENTURI members: Jules Lavalou (IBDM), Qiyan Mao (IBDM), Stefan Harmansa (IBDM), Stephen Kerridge (IBDM), Annemarie C. Lellouch (IBDM), Jean-Marc Philippe (IBDM) Thomas Lecuit (IBDM).
Abstract: Interfaces between cells with distinct genetic identities elicit signals to organize local cell behaviors driving tissue morphogenesis. The Drosophila embryonic axis extension requires planar polarized enrichment of myosin-II powering oriented cell intercalations. Myosin-II levels are quantitatively controlled by GPCR signaling, whereas myosin-II polarity requires patterned expression of several Toll receptors. How Toll receptors polarize myosin-II and how this involves GPCRs remain unknown. Here, we report that differential expression of a single Toll receptor, Toll-8, polarizes myosin-II through binding to the adhesion GPCR Cirl/latrophilin. Asymmetric expression of Cirl is sufficient to enrich myosin-II, and Cirl localization is asymmetric at Toll-8 expression boundaries. Exploring the process dynamically, we reveal that Toll-8 and Cirl exhibit mutually dependent planar polarity in response to quantitative differences in Toll-8 expression between neighboring cells. Collectively, we propose that the cell surface protein complex Toll-8/Cirl self-organizes to generate local asymmetric interfaces essential for planar polarization of contractility.