EMBO/SourceData huggingface dataset:
Figure 7(A) ADP-Glo ATPase assay showing stimulation of S. cerevisiae Hrr251-394 (blue circles), Hrr251-394 K38R (red diamonds), Hrr25 full-length:Mam187-191 (black triangles), Hrr251-394:Mam187-191 (orange squares), and Hrr251-394:Mam187-191 R131A (green triangles) by bovine casein. See Figure EV6A for SDS-PAGE analysis of purified proteins.(B) Stimulation of Hrr251-394, Hrr251-394:Mam187-191, and Hrr251-394:Mam187-191 R131A by ATP, measured using an enzyme-coupled ATPase assay.(C) ADP-Glo assay showing the effect of added CK1-7 on Hrr251-394, Hrr251-394:Mam187-191, and Hrr251-394:Mam187-191 R131A.(D) Km, Vmax, and IC50 values for tested enzymes. Vmax was calculated from curves in (A) at 100 M ATP.
Figure 8(A) Phos-tag gels showing phosphorylation of purified S. cerevisiae Mtw1 complex by Hrr251-394 and Hrr251-394:Mam187-191. Asterisks denote N-terminal proteolytic cleavage products of Dsn1, with the red asterisk denoting a previously-characterized product lacking the first 171 residues (Hornung et al, 2011).
Figure 1Pre-enriched thymocytes from WT BALB/c thymi as in (a) were labeled by CFSE (CFSE+), mixed with pre-enriched thymocytes from SKG thymi (CFSE-), loaded with Indo-1, and stimulated as in (a). Ratio of Indo (Violet) and Indo (Blue) was analyzed by flow cytometry. Comparison of cytoplasmic Ca2+ profiles between WT and SKG NKT1 (c) and NKT2 (d) cells in the same test tube are shown. Data are representative from one of at least three independent experiments. Graphs represent the average Ca2+ levels.
Figure 2Sorted thymic NKT1 and NKT2 cells were labeled with CellTrace Violet, and activated by anti-CD3ε/CD28 Dynabeads for 2 days, in the presence of different [EGTA] in the medium. CellTrace Violet/CTV signal in living cells at the end of the culture is shown. Cell proliferation was quantified as division index based on CTV signals in (a).Thymic lobes from new born (day 0) BALB/c mice were cultured in vitro for 6 days. EGTA was added 48h after the start of culture (day 2), and the expression of CXCR3 (g), PLZF (h) and PD1 (i) in total iNKT cells are shown.
Figure 3oxygen consumption rate (OCR) from sorted thymic T cell populations measured in a Seahorse Mitostress test;
Figure 4Confocal images of Tim 23 (Alexa Fluor 488, green) and MitoTracker deep red (Alexa Fluor 647, red) in freshly isolated thymic NKT1 (c1, 2) and NKT2 (c5, 6) cells using Airyscan technology. 3D images reconstructed by Imaris software in NKT1 (c3, 4) and NKT2 cells(c7, 8). Dotted line in panel (5-8) indicates juxtaposition of two NKT2 cell images taken with the same resolution and magnification as NKT1 cells.Representative images of electron microscopy in NKT1 and NKT2 cells; (f) individual mitochondria size and (g) cristae perimeters normalized to mitochondria perimeter based on EM in (e).
Figure 5Maximal cytoplasmic [Ca2+] in single, freshly sorted NKT1 and NKT2 cells following TCR stimulation in the presence or absence of BTP2 (1uM);BTP2 (1uM) was added 48h after the start of culture, and the expression of Tbet in total iNKT cells is shown. Data are representative from one of three independent experiments. Graphs represent mean ± SD with symbols representing individual cells (a), or individual thymic lobes (b-f). **p < 0.01; ****p < 0.0001; n.s. not significant (unpaired two-tailed Student's t test).BTP2 (1uM) was added 48h after the start of culture, and the expression of CXCR3 (d), PLZF (e), and PD1 (f) in total iNKT cells is shown. Data are representative from one of three independent experiments. Graphs represent mean ± SD with symbols representing individual cells (a), or individual thymic lobes (b-f). **p < 0.01; ****p < 0.0001; n.s. not significant (unpaired two-tailed Student's t test).
Figure 6Profiles showing average Ca2+ influx induced by Thapsigargin (TG) in freshly sorted NKT1 (Red) and NKT2 (Black) cells. The timing of TG (1uM), ionomycin (Iono) (2uM) and CCCP (1uM) addition, and extracellular [Ca2+] in mM are shown.
Figure 1A, B. HeLa cells treated with non-targeting siRNA (Ctrl) or C9orf72 siRNA and transfected with mCherry-EGFP-LC3 were treated with vehicle (Ctrl), Torin1 (250 nM; 3 h), bafilomycin A1 (100 nM; 6 h - BafA1) or combinations thereof as indicated. Autophagosomes (green+red) and autolysosomes (red only) were quantified per cell (Mean ± SEM from 3 independent experiments; one-way ANOVA with Fisher's LSD test: ns, not significant, * p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001, **** p ≤ 0.0001; N (cells) = Ctrl/Ctrl: 120; Ctrl/Torin1: 101; C9orf72/Ctrl: 99; C9orf72/Torin1: 106; Ctrl/BafA1: 116; Ctrl/Torin1/BafA1: 118; C9orf72/BafA1: 109; C9orf72/Torin1/BafA1: 106). Scale bar = 20 µm. C9orf72 knockdown was confirmed by RT-qPCR (Appendix Fig S2).C, D. HEK293 cells treated with non-targeting (Ctrl) or C9orf72 siRNA were incubated with BafA1, BafA1+Torin1 (C) or BafA1+rapamycin (D) and levels of LC3-I and II were determined on immunoblots. Levels of LC3-II were normalized against α-tubulin and are shown relative to the BafA1-treated sample (Mean ± SEM; one-way ANOVA with Fisher's LSD test: ns, not significant, * p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001, **** p ≤ 0.0001; N = 3 experiments).E, F. Primary cortical neurons (DIV5/6) were transfected with ECFP non-targeting (Ctrl) or C9orf72 miRNA (cyan) and EGFP-LC3 (green). 3 days post transfection neurons were treated with vehicle (Ctrl), Torin1 (250 nM; 3 h), BafA1 (100 nM; 5 h) or combinations thereof as indicated. Autophagosomes were quantified as the number of EGFP-LC3 positive puncta per soma from 2 independent experiments (Mean ± SEM; one-way ANOVA with Fisher's LSD test: ns, not significant, * p ≤ 0.05; *** P ≤ 0.001; **** P ≤ 0.0001; N (cells) = Ctrl miRNA/Ctrl: 77; Ctrl miRNA/Torin1: 68; C9orf72 miRNA/Ctrl: 57; C9orf72 miRNA/Torin1: 69; Ctrl miRNA/BafA1: 35; Ctrl miRNA/Torin1/BafA1: 57; C9orf72 miRNA/BafA1: 66; C9orf72 miRNA/Torin1/BafA1: 64). Scale bar = 5 µm.
Figure 2A. HEK293 cells treated with non-targeting (Ctrl) or FIP200 siRNA were co-transfected with EGFP-LC3 and either empty vector control (EV), Myc-C9orf72S or Myc-C9orf72L. 24 h post transfection cells were treated with vehicle or 100 nM BafA1 for 6 h. Samples were lysed and subjected to SDS-PAGE and immunoblot. Autophagy levels were determined by immunoblot for EGFP-LC3-I and II. Expression of Myc-C9orf72 was confirmed using anti-Myc (* indicates a nonspecific band). FIP200 knockdown was confirmed using anti-FIP200 antibodies. α-tubulin was used as loading control.B. HeLa cells treated with non-targeting (Ctrl) or FIP200 siRNA were co-transfected with empty vector (EV), Myc-C9orf72S or Myc-C9orf72L (red) and EGFP-LC3 (green) to label autophagosomes. As positive control EV transfected cells were treated for 3 h with Torin1 (250 nM). Autophagy was quantified as the number of EGFP-LC3 positive autophagosomes per cell from 3 independent experiments (Mean ± SEM; one-way ANOVA with Fisher's LSD test: **** P ≤ 0.0001, N (cells) = Ctrl/EV: 73; FIP200/EV: 76; Ctrl/EV/Torin1: 73, FIP200/EV/Torin1: 70; Ctrl/C9orf72L: 71; FIP200/C9orf72L: 74; Ctrl/C9orf72S: 72; FIP200/C9orf72S: 72). Scale bar = 20 µm. FIP200 knockdown was confirmed by immunoblot (Appendix Fig S2).
Figure 4A. HEK293 cells were transfected with non-targeting (Ctrl) or C9orf72 siRNA. Cells were treated with rapamycin for 6 h to induce autophagy. Activation of ULK1 was determined on immunoblots using phospho-ULK1 (Ser757), total ULK1 and GAPDH Abs (loading control).B. HeLa cells treated with non-targeting (Ctrl) or C9orf72 siRNA were transfected with mCherry-FIP200. 24 h post transfection cells were treated for 3 h with Torin1 (250 nM) or vehicle (Ctrl). Translocation of the ULK1 complex was quantified as the number of mCherry-FIP200 positive puncta per cell from 3 independent experiments (Mean ± SEM; one-way ANOVA with Fisher's LSD test, ns: not significant, **** P ≤ 0.0001; N (cells) = Ctrl/Ctrl: 65; Ctrl/Torin1: 60; C9orf72/Ctrl: 54; C9orf72/Torin1: 49). C9orf72 knockdown was determined by RT-qPCR (Appendix Fig S2). Scale bar = 10 µm.C. Primary cortical neurons (DIV5/6) were transfected with EmGFP non-targeting (Ctrl) or C9orf72 miRNA (green) and mCherry-FIP200 (red); for rescue experiments the cells were additionally transfected with mCerulean-tagged C9orf72s and C9orf72L (cyan). 3 days post transfection neurons were treated for 3 h with Torin1 (250 nM) or vehicle (Ctrl). Translocation of the ULK1 complex was quantified as the number of mCherry-FIP200 positive puncta per soma from 2 independent experiments (Mean ± SEM; one-way ANOVA with Fisher's LSD test, ns: not significant, *** P ≤ 0.001, **** P ≤ 0.0001; N (cells) = Ctrl miRNA/Ctrl: 134; Ctrl miRNA/Torin1: 125; C9orf72 miRNA/Ctrl: 101; C9orf72 miRNA/Torin1: 78; C9orf72 miRNA+C9orf72L+C9orf72S: 41; C9orf72 miRNA+C9orf72L+C9orf72S/Torin1: 39). Scale bar = 5 µm.D. HeLa cells were co-transfected with mCherry-FIP200 (red) and empty vector (EV), FLAG-C9orf72L or FLAG-C9orf72S (green). As positive control EV transfected cells were treated for 3 h with Torin1 (250 nM). Translocation of the ULK1 complex was quantified as the number of mCherry-FIP200 positive puncta per cell from 3 independent experiments (Mean ± SEM; one-way ANOVA with Fisher's LSD test, *** P ≤ 0.001, **** P ≤ 0.0001); N (cells) = EV: 47, EV + Torin1: 31, C9orf72L: 46, C9orf72S: 45). Scale bar = 10 µm.
Figure 5A, B. HeLa cells (A) or SH-SY5Y neuroblastoma cells (B) treated with non-targeting (Ctrl) or Rab1a siRNA were co-transfected with mCherry-FIP200 (red) and empty vector (EV), Myc-C9orf72L or Myc-C9orf72S (green). As positive control EV transfected cells were treated for 3 h with Torin1 (250 nM). Translocation of the ULK1 complex was quantified as the number of mCherry-FIP200 positive puncta per cell (A, HeLa, Mean ± SEM; one-way ANOVA with Fisher's LSD test; ns, not significant; **** P ≤ 0.0001; N (cells from 3 independent experiments) = Ctrl/EV: 81; Ctrl/EV/Torin1: 48; Ctrl/C9orf72L: 86; Ctrl/C9orf72S: 48; Rab1a/EV: 79; Rab1a/EV/Torin1: 68; Rab1a/C9orf72L: 78; Rab1a/C9orf72S: 52; B, SH-SY5Y: Mean ± SEM; one-way ANOVA with Fisher's LSD test; ns, not significant; ** P ≤ 0.01; **** P ≤ 0.0001; N (cells from 2 independent experiments) = Ctrl/EV: 70; Ctrl/EV/Torin1: 56; Ctrl/C9orf72L: 45; Ctrl/C9orf72S: 43; Rab1a/EV: 63; Rab1a/EV/Torin1: 55; Rab1a/C9orf72L: 44; Rab1a/C9orf72S: 37). Rab1a knockdown was confirmed by RT-qPCR (Appendix Fig S2). Scale bar = 10 µm.C. SH-SY5Y neuroblastoma cells treated with non-targeting (Ctrl) or Rab1a siRNA were co-transfected with EGFP-LC3 (green) and empty vector (EV), Myc-C9orf72L or Myc-C9orf72S (red). As positive control EV transfected cells were treated for 3 h with Torin1 (250 nM). Autophagosomes were quantified as the number of EGFP-LC3 positive puncta per cell (Mean ± SEM; one-way ANOVA with Fisher's LSD test; ns, not significant; * P ≤ 0.05, *** P ≤ 0.001, **** P ≤ 0.0001; N (cells from 2 independent experiments) = Ctrl/EV: 102; Ctrl/EV/Torin1: 92; Ctrl/C9orf72L: 97; Ctrl/C9orf72S: 76; Rab1a/EV: 102; Rab1a/EV/Torin1: 107; Rab1a/C9orf72L: 101; Rab1a/C9orf72S: 87). Rab1a knockdown was confirmed by RT-qPCR (Appendix Fig S2). Scale bar = 10 µm.
Figure 6B. Cell lysates of HEK293 cells co-transfected with Myc-Rab1a and either empty vector, FLAG-C9orf72S or FLAG-C9orf72L were subjected to immunoprecipitation with anti-FLAG antibody. Bound protein was eluted from beads using excess FLAG peptide. Immune eluates were probed for FLAG-C9orf72 and Myc-Rab1a on immunoblots. The input levels of FLAG-C9orf72 and Myc-Rab1a in the transfected cells are shown (Inputs).* indicates remaining Myc-Rab1a signal after reprobing for FLAG-C9orf72.C. Cell lysates of HEK293 cells transfected with Myc-C9orf72S or Myc-C9orf72L were subjected to immunoprecipitation with anti-Myc antibody. The resulting immune pellet was probed for endogenous Rab1a.D. 35S-radiolabelled recombinant Myc-Rab1a protein loaded with vehicle, GDP or GMP-PNP was added to GST, GST-C9orf72S and GST-C9orf72L immobilized on glutathione-coated beads. 35S-radiolabelled recombinant Myc-Rab1a protein was visualized by autoradiography (top panel). Coomassie-stained GST, GST-C9orf72S and GST-C9orf72L in the pull-down samples are shown (bottom panel). The identity of the Coomassie protein bands was confirmed by mass spectrometry (# = E. coli DnaK Chaperonin; * = E. coli 60kD Chaperonin; Appendix Fig S3). Relative binding of Rab1a to C9orf72 was quantified from 3 independent experiments (Mean ± SEM; one-way ANOVA with Fisher's LSD test; ns, not significant; * P ≤ 0.05; ** P ≤ 0.01; *** P ≤ 0.001).E. Increasing volumes of 35S-radiolabelled recombinant Myc-C9orf72L protein were incubated with equal amounts of GST-Rab1a immobilized on glutathione-coated beads in an equilibrium binding experiment. 8 µl of 35S-radiolabelled recombinant Myc-C9orf72L protein was incubated with GST as a negative control. Bound 35S-radiolabelled Myc-C9orf72L protein was visualized by phosphoimager. Coomassie stained GST-Rab1a and GST in the pull down samples are shown. Densitometry analysis of the amount of 35S-radiolabelled recombinant Myc-C9orf72L protein bound to GST-Rab1a in the different binding reactions was used to fit an equilibrium binding hyperbola (R2=0.94).
Figure 7A. HEK293 cells treated with non-targeting (Ctrl) or C9orf72 siRNA were transfected with HA-ULK1, Myc-Rab1a or HA-ULK1+Myc-Rab1a as indicated. Transfections were laced with mVenus to enable identification of transfected cells for analysis (green). Transfected cells were probed with anti-HA and anti-Myc antibodies and processed for PLA. PLA proximity signals (red) per cell were determined from 3 independent experiments (Mean ± SEM; one-way ANOVA with Fisher's LSD test, **** P ≤ 0.0001); N (cells) = Ctrl/HA-ULK1: 125, Ctrl/Myc-Rab1a: 149, Ctrl/HA-ULK1+Myc-Rab1a: 163, C9orf72/HA-ULK1: 136, C9orf72/Myc-Rab1a: 133, C9orf72/HA-ULK1+Myc-Rab1a: 155). Scale bar = 20µm.B. HeLa cells treated with non-targeting (Ctrl) or C9orf72 siRNA were co-transfected with mCherry-FIP200 (red) and empty vector (EV) or Myc-Rab1a(Q70L) (green). Translocation of the ULK1 complex was quantified as the number of mCherry-FIP200 positive puncta per cell from 4 independent experiments (Mean ± SEM; one-way ANOVA with Fisher's LSD test, * P ≤ 0.05, **** P ≤ 0.0001); N (cells) = Ctrl/EV: 101; Ctrl/Q70L: 106; C9orf72/Q70L: 42. C9orf72 knockdown was determined by RT-qPCR (Appendix Fig S2). Scale bar = 10 µm.C. HeLa cells treated with non-targeting (Ctrl) or C9orf72 siRNA were co-transfected with EGFP-LC3 (green) and empty vector (EV) or Myc-Rab1a(Q70L) (red). Autophagosomes were quantified as the number of EGFP-LC3 positive puncta per cell (Mean ± SEM; one-way ANOVA with Fisher's LSD test, ** P ≤ 0.01, **** P ≤ 0.0001); N (cells) = Ctrl/EV: 44; Ctrl/Q70L: 32; C9orf72/Q70L: 47. C9orf72 knockdown was determined by RT-qPCR (Appendix Fig S2). Scale bar = 10 µm.
Figure 8A. HeLa cells treated with non-targeting (Ctrl) or C9orf72 siRNA were immunostained for endogenous p62. Accumulation of p62 was quantified by counting p62 positive puncta per cell from 3 independent experiments (Mean ± SEM; unpaired t-test, **** P ≤ 0.0001); N (cells) = Ctrl: 74, C9orf72: 55). C9orf72 knockdown was confirmed by RT-qPCR (Appendix Fig S2). Scale bar = 10 µm.B. Primary cortical neurons (DIV5) were transduced with 4TU/cell EmGFP non-targeting control miRNA (Ctrl) or C9orf72 miRNA (green); for rescue experiments the cells were additionally transduced with 4TU/cell mVenus-tagged C9orf72s and C9orf72L (verified by immunoblot, Appendix Fig S2). Neurons were immunostained for endogenous p62 3 days post transduction. Accumulation of p62 was quantified by counting p62 positive puncta per soma from 2 independent experiments (Mean ± SEM; one-way ANOVA with Fisher's LSD test, ** P ≤ 0.01; N (cells) = Ctrl miRNA: 80; C9orf72 miRNA: 80; C9orf72 miRNA+C9orf72L+C9orf72S: 75). Scale bar = 10 µm.
Figure 1(A) Wild-type primary B cells were treated with 5 μg/mL of anti-kappa antibody (a-k chain, top) or 1 µM LatrunculinA (LatA, bottom). Intracellular calcium flux was measured by flow cytometry in the presence of Src-inhibitor (PP2), Syk-inhibitor (BAY 613606) or vehicle control.(B) Wild-type primary B cells were treated with vehicle control (-), 5 μg/mL anti-kappa antibody or 1 µM LatA for the indicated time. Cells were lysed and analysed by SDS-PAGE followed by immunoblotting with phospho-Lyn (Y507) and actin as loading control. The intensity of phosphorylated proteins, normalized to actin, was referred to the respective unstimulated sample, set as 1.(C and D) Wild-type primary B cells were treated with vehicle control (-), 5 µg/mL anti-kappa antibody or 1 µM LatA for the indicated time. Cells were lysed and analysed by SDS-PAGE followed by immunoblotting with phospho-Syk (pSyk), phospho-CD19 (pCD19), phospho-Akt (pAkt), phospho-ERK (pERK) and total ERK as loading control. The intensity of phosphorylated proteins, normalized to ERK, was referred to the respective unstimulated sample, set as 1.(E and F) Wild-type primary B cells were treated with vehicle control (-), 5 µg/mL anti-kappa antibody or 1 µM LatA for the indicated time. Cells were lysed and analysed by SDS-PAGE followed by immunoblotting with phospho-PLCγ2 (pPLCγ2) and total ERK as loading control. The intensity of phosphorylated proteins, normalized to ERK, was referred to the respective unstimulated sample, set as 1.(G and H) Wild-type primary B cells were treated with vehicle control (-), 5 µg/mL anti-kappa antibody or 1 µM LatA for the indicated time. Cells were lysed and analysed by SDS-PAGE followed by immunoblotting with phospho-CD22 (pCD22), phospho-SHP1 (pSHP1), and CD22 or total ERK as loading controls. The intensity of phosphorylated proteins, normalized to CD22 or ERK, was referred to the respective unstimulated sample, set as 1.(I) Wild-type and Cd22-/- primary B cells were treated with 5 µg/mL anti-kappa antibody or 1 µM LatA and intracellular calcium flux was measured by flow cytometry.(J) Wild-type and Cd22Y2,5,6F primary B cells were treated with 5 µg/mL anti-kappa antibody or 1 µM LatA and intracellular calcium flux was measured by flow cytometry.(K and L) Wild-type, Cd22-/- and Cd22Y2,5,6F primary B cells were treated with vehicle control (-) or 1 µM LatA for the indicated time. Cells were lysed and analysed by SDS-PAGE followed by immunoblotting with phospho-CD19 (pCD19), phospho-Akt (pAkt), phospho-ERK (pERK) and actin as loading control. The intensity of phosphorylated proteins, normalized to actin, was referred to the unstimulated sample of the wild type cells, set as 1.
Figure 2(A) Determining the number and density of CD22, CD19, IgM and IgD on the surface of wild-type primary B cells. Cells were stained with PE-conjugated antibody against CD22 (blue profile), CD19 (red profile), IgM (red profile) or IgD (red profile) and their fluorescence profiles compared to those of standard beads (grey profiles), which each possess a well-defined number of binding sites (st0=blank, st1-st4=increasing number of binding sites) against the primary antibody. For IgM, where the range of expression is large, the low and high 25 percentiles were calculated as in Mattila et al. 2013 and shown in brackets.Data are representative of three independent experiments.(B-E) Dual-colour SIM analysis of CD22, IgM, IgD and CD19. Wild-type primary B cells were fixed, stained with Atto633 or 488-conjugated antibody against CD22, IgM or IgD and Alexa647-conjugated antibody against CD19 and settled onto nonstimulatory coverslips. Cells were then embedded in agarose, imaged with SIM and analysed.(B) SIM images of CD22, IgM, IgD and CD19.(C) Cross-correlation function.(D) Pearson correlation coefficient.(E) Cluster size calculated from autocorrelation analysis.
Figure 5(A-C) Single-particle-tracking of CD22, CD19, IgM and IgD. Wild-type primary B cells were stained with Atto633-conjugated Fab fragments against CD22, CD19, IgM and IgD, settled onto nonstimulatory coverslips and imaged. Single particle trajectories were then analysed.(A) Trajectories of CD22 showing diffusion of single particles over 6 s.(B) Magnified region from (A) traces one particle (current position indicated with white dashed circle, trajectory in red) over 6 s.(C) Diffusion coefficients of 300 representative CD22, CD19, IgM and IgD particles. Bars indicate the median. Data are pooled from at least three experiments per receptor. *P < 0.0001 (Student's t-test).(D-F) Single-particle-tracking of CD22 in primary LifeAct-GFP-expressing B cells. Cells were labelled with Atto633-conjugated Fab fragments against CD22, settled onto nonstimulatory coverslips and imaged. Single particle trajectories were then analysed.(D) Trajectories of CD22 (left) showing diffusion of single particles over 6 s and overlaid with a still image of F-actin intensity (middle). Areas of high F-actin density (grey line boundaries) with trajectories of CD22 classified as being inside (red) and outside (blue) of F-actin rich areas.(E) Diffusion coefficients of CD22 particles from (D) whose trajectories were classed as inside (in) or outside (out) of actin rich areas. The overall diffusion is also shown (all). Bars and numbers are the median. Data are pooled from two different experiments. *P < 0.0001 (Student's t-test).(F) Correlation analysis. For each position in each CD22 track, the actin intensity was measured and compared to the same number of random positions on the same cell. Values from different cells were normalized so that the average intensity in F-actin rich regions corresponds to a value of one and the average for F-actin low regions to zero.(G) Wild-type primary B cells were labelled with Atto633-conjugated Fab fragments against CD22, settled onto nonstimulatory coverslips and treated with vehicle control (DMSO) or 1µM LatA. Single particle trajectories were then analysed. Bars and numbers indicate the median. Data are pooled from two experiments.*P < 0.0001 (Student's t-test).(H-J) Wild-type primary B cells were stained with Alexa647-conjugated antibody against CD22 and settled onto nonstimulatory coverslips. Cells were then fixed, imaged with dSTORM and analysed.(H) 2D (top) and pseudo 3D (bottom) dSTORM images were reconstructed from single molecule localizations. The white dashed square is shown in pseudo 3D (bottom).(I-J) Quantification of the distribution of CD22 Hopkins index and with H function. Error bars (Hopkins index) and thin lines (H function) denote mean ± SEM.Data are pooled from two different experiments.(K) Flow cytometric analysis of F-actin by intracellular phalloidin staining of unstimulated or LatA treated wild-type B cells for the indicated length of time.(L) Flow cytometric analysis of CD22 surface expression in resting or stimulated B cells with 10µg/ml anti-µ chain (Jackson ImmunoResearch), 1µM or 10µM LatA for 5 and 15 minutes. Error bars denote mean ± SD.