Fig. 6: CD97 promotes cell membrane retraction through activation of RhoA.
From: Dynamic encounters with red blood cells trigger splenic marginal zone B cell retention and function
a, HEK293T cells were transfected with CD97 (WT)–GFP, CD97 (T419G)–GFP or CTF–GFP fusion constructs. Longest diameters of individual WT- (n = 62), T419G- (n = 62) and CTF-transfected (n = 63) cells are shown. Each symbol represents one cell. One of three independent experiments with similar results is shown. b, Schematic diagram of an optically trapped ligand-coated bead applying pulling force while in contact with the cell membrane. The cell is also indicated to contain an anillin–GFP RhoA biosensor. c,d, HEK293T cells were cotransduced with anillin–GFP RhoA biosensor and CD97 (WT)–Scarlet, CD97 (T419G)–Scarlet or CD97 (PBM)–Scarlet fusion lentivirus and sorted. c, Cell trap forces of individual WT- (n = 70), T419G- (n = 64) and PBM-transduced (n = 62) cells. d, Normalized active RhoA biosensor fluorescence intensity of WT- (n = 27), T419G- (n = 20) and PBM-transduced (n = 32) cells as indicated. e–g, Examples of anillin–GFP active RhoA biosensor signals at the site of bead contact and membrane tether (blue arrowhead) of one HEK293T cell expressing CD97 (WT)–GFP fusion (e), CD97 (T419G)–GFP fusion (f) or CD97 (PBM)–GFP fusion (g) protein. The blue arrowhead indicates the site of bead pulling. The time series begins at the start time for pulling, which was about 30 s after the bead contacted the cell. See corresponding Supplementary Videos 7–12; scale bar, 5 μm (e and f); scale bar, 3 μm (g). Data are representative of three independent experiments (a) or a pool from two (c–g) independent experiments. Statistical significance was tested by one-way ANOVA followed by a Tukey’s multiple-comparisons test (a and c) or mixed-effects analysis followed by a Geisser–Greenhouse correction (d).
