PT  - JOURNAL ARTICLE
AU  - Parijat Sil
AU  - Nicolas Mateos
AU  - Sangeeta Nath
AU  - Sonja Buschow
AU  - Carlo Manzo
AU  - Kenichi G. N. Suzuki
AU  - Takahiro Fujiwara
AU  - Akihiro Kusumi
AU  - Maria F. Garcia-Parajo
AU  - Satyajit Mayor
TI  - Dynamic actin-mediated nano-scale clustering of CD44 regulates its meso-scale organization at the plasma membrane
AID  - 10.1101/751834
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 751834
4099  - http://biorxiv.org/content/early/2019/08/30/751834.short
4100  - http://biorxiv.org/content/early/2019/08/30/751834.full
AB  - Transmembrane adhesion receptors at the cell surface, such as CD44, are often equipped with modules to interact with the extracellular-matrix(ECM) and the intra-cellular cytoskeletal machinery. CD44 has been recently shown to compartmentalize the membrane into domains by acting as membrane pickets, facilitating the function of signaling receptors. While spatial organization and diffusion studies of membrane proteins are usually conducted separately, here we combine observations of organization and diffusion by using high spatio-temporal resolution imaging on living cells to reveal a hierarchical organization of CD44. CD44 is present in a meso-scale meshwork pattern where it exhibits enhanced confinement and is enriched in nano-clusters of CD44 along its boundaries. This nanoclustering is orchestrated by the underlying cortical actin dynamics. Interaction with actin is mediated by specific segments of the intracellular-domain(ICD). This influences the organization of the protein at the nano-scale, generating a selective requirement for formin over Arp2/3-based actin-nucleation machinery. The extracellular-domain(ECD) and its interaction with elements of ECM do not influence the meso-scale organization, but may serve to reposition the meshwork with respect to the ECM. Taken together, our results capture the hierarchical nature of CD44 organization at the cell surface, with active cytoskeleton-templated nano-clusters localized to a meso-scale meshwork pattern.