RT Journal Article SR Electronic T1 Plasma membrane topography governs the three-dimensional dynamic localization of IgM B cell receptor clusters JF bioRxiv FD Cold Spring Harbor Laboratory SP 2022.04.29.489661 DO 10.1101/2022.04.29.489661 A1 Saltukoglu, Deniz A1 Özdemir, Bugra A1 Holtmannspötter, Michael A1 Reski, Ralf A1 Piehler, Jacob A1 Kurre, Rainer A1 Reth, Michael YR 2022 UL http://biorxiv.org/content/early/2022/04/29/2022.04.29.489661.abstract AB B lymphocytes recognize bacterial or viral antigens via different classes of the B cell antigen receptor (BCR). Protrusive structures termed microvilli cover lymphocyte surfaces and are thought to perform sensory functions in screening antigen-bearing surfaces. Here, we have studied the cell surface features of Ramos B cells and the spatiotemporal organization of the IgM-BCR using lattice light sheet microscopy in combination with tailored custom-built 4D image analysis. Ramos B cell surfaces were found to form dynamic networks of elevated ridges bridging individual microvilli. A proportion of membrane-localized IgM-BCR was found in clusters, which were associated with the ridges and the microvilli. The dynamic ridge network organization and the IgM-BCR cluster mobility were linked and both were controlled by Arp2/3 complex activity. Our results suggest that topographical features of the cell surface govern the distribution and dynamic localization of IgM-BCR clusters to facilitate antigen screening.Competing Interest StatementThe authors have declared no competing interest.