EMBO/SourceData huggingface dataset:
Figure 1 Pregnant dams were injected with 4-OHT at days E10.5 and E11.5 for analysis at day E12.5 or E10.5, E11.5, and E12.5 of development for later times of analysis Developmental loss of VE-cadherin leads to severe edema. Fetuses of the genotypes listed in the top row were analyzed at the developmental stages in the first column. Numbers in brackets denote embryos with signs of edema. Last column lists the percentage of viable fetuses in the VE-cadherin deleted cohort Fetuses were explanted at day E14.5. Arrowheads indicate prominent edema along the back. The images are representative for 42 (Cdh5lox/lox) and 25 (Cdh5lox/lox; Prox1-CreERT2) analyzed animals Pregnant dams were injected with 4-OHT at days E10.5 and E11.5 for analysis at day E12.5 or E10.5, E11.5, and E12.5 of development for later times of analysis Skin wholemount preparations stained for PROX1, PECAM1 and VEGFR-3. Maximum intensity projections (MIPs) of tiled confocal stacks (Cdh5lox/lox 2075µm x 2075µm, z=50µm; Cdh5lox/lox; Prox1-CreERT2 3765µm x 3765 µm, z=61µm). Scale bars = 100 μm. The data are representative for 6 (Cdh5lox/lox) and 6 (Cdh5lox/lox; Prox1-CreERT2) analyzed animals from 3 litters Pregnant dams were injected with 4-OHT at days E10.5 and E11.5 for analysis at day E12.5 or E10.5, E11.5, and E12.5 of development for later times of analysis Enumeration of the PROX1-expressing (PROX1+) nuclei in three different VE-cadherin deleted wholemount preparations analogous to Fig. 1B. Nuclei were counted in a MIP corresponding to an area of 1.5 mm2 and normalized to the number of nuclei in Cdh5lox/lox control preparations The area covered by lymphatic vessels was determined in the samples evaluated in (D) and is depicted as relative area compared to Cdh5lox/lox controls. The calculations and measurements were obtained from three animals and three confocal stacks per biological group. PROX1-positive nuclei were counted using the particle analysis tool of Fiji
Figure 2 Deletion of VE-cadherin in lymphatic endothelial cells of newborn pups was induced by two optimal doses of 4-OHT at days P2 and P4. For analysis 6 weeks later ear punches were subjected to wholemount immunostaining of the dermal vasculature. A-H (A, B, E, F) Overview MIPs of ear skin wholemount preparations immunostained for the indicated antigens. VEC, VE-cadherin; PRX, PROX1. (C, D, G, H) Magnified views of the areas in the red boxes in (A, E). Areas delimited by the stippled yellow boxes in (C) and (G) are enlarged in the insets (yellow solid boxes). Yellow arrows indicate widened lumen, yellow arrowheads denote oak leaf-shaped LECs with discontinuous junctions. Scale bars in (A and E) correspond to 100 μm and in (C and G) to 50 µm. The data are representative for 6 (Cdh5lox/lox) and 5 (Cdh5lox/lox; Prox1-CreERT2) analyzed animals from 2 litters
Figure 3 A-L VE-cadherin deletion was initiated either in newborn pups (A, B, E, F) by two applications of 4-OHT at days P2 and P4 or in mice at 11 weeks (C, G) and 42 weeks (D, H) of age (three applications of Tamoxifen at 2 day intervals via oral gavage). Ear skins were prepared 6 weeks (A, B, E, F) or 5 weeks (C, D, G, H) after induction and immunostained for the indicated proteins. Shown are MIPs of confocal tile scans (approx. 750 µm x 750 µm) covering 40 µm in depth. White arrows in (F) highlight distorted and partially fragmented lymphatic vessels and white arrowheads denote aberrantly pointed vessels (F). (I-L) Lymphatic valves in the dermis of the ear were maintained for 5 weeks despite deletion of VE-cadherin at 11 weeks of age (yellow arrows in K, L). PEC1, PECAM1; PRX1, PROX1;VR3, VEGFR-3. Scale bars correspond to 100 μm. The data represent wholemount stainings from 6 (A, E), 5 (B, F), 6 (C, G, K, L), 3 (D, H) and 6 (I, J) analyzed animals
Figure 4  Fig. 4: VE-cadherin is indispensable for the maintenance of mesenteric lymphatic vessels at all ages. A-F Deletion of VE-cadherin was induced in mice at various age (4 weeks (A), neonate (B), 6 month (C, D, E) or 1 year (F)) by either two applications of 4-OHT at days P2 and P4 (neonates) or three applications of Tamoxifen at 2 day intervals via oral gavage (all other ages). The mesentery was prepared as indicated 4, 6, 8 or 11 weeks later and the wholemount preparations were immunostained for the proteins specified in color (left). (B) Inset in top panel shows a magnification of the area outlined by the white dashed line (for further magnification see expanded view Fig. 1A and B). Arrows indicate the previous position of lymphatic valves; white arrowheads indicate PECAM1+ capillaries supplying the intestinal fat tissue lining the vessels (magnified in expanded view Fig. 1C); yellow arrowheads denote island of LECs that display intracellular VEGFR-3 staining. (C) Arrows denote LECs that have converted from growth as tubes to sheets; white arrowheads, thinning of lymphatic vessels; yellow arrowheads, aberrant sprouting of LECs. The area outlined by a white box is depicted magnified in (D) and provides details on LECs growing as a sheet of cells. (E) Formation of ectopic sprouts from the valve area of degenerating lymphatic vessels. (F) Fully deteriorated lymphatic vessel with emanating sprouts that initiate sheet-like growth. PEC1, PECAM1; PRX1, PROX1; VR3, VEGFR-3. Scale bars = 100 μm. The data represent n=5 (A), n=5 (B), n=3 (C-E) and n=6 (F) animals.
Figure 5  Fig. 5: Deletion of VE-cadherin results in fragmentation and distension of the intestinal lacteals. A-E Deletion of VE-cadherin was induced in mice at various ages (neonatal (C), 16 weeks (D) or 1 year (E)) by either two applications of 4-OHT at days P2 and P4 (neonates) or three applications of Tamoxifen at 2 day intervals via oral gavage (all other ages).Control mice of the same age were subjected to an identical regimen (A, B). Intestinal wholemount preparations of the jejunum and ileum were generated 5 - 8 weeks after Tamoxifen induction and immunostained for the indicated proteins, scale bars = 100 μm. The data represent wholemount stainings from 3 (D), 5 (B,E) and 6 (A, C) animals analyzed for each genotype.
Figure 6Deletion of VE-cadherin was induced in adult mice (13 weeks) and EdU incorporation into PROX1-positive cell nuclei was determined 6 weeks after Tamoxifen administration. Shown are mesenteric wholemount stainings prepared from control (A, B; n=3) or VE-cadherin-deleted mice (C, D; n=3). (B) and (D) show a magnification of the area outlined by the white dashed line in (A) and (C). Antigens shown in addition to the EdU incorporation are depicted in colour on the left side of the first panel. PEC, PECAM1; PRX1, PROX1. Scale bars = 100 µm Enumeration of EdU-positive LECs. The measurements were obtained from three animals and nine confocal stacks per biological group. PROX1-positive nuclei were counted using the particle analysis tool of Fiji. Co-localization of PROX1 and EdU was determined manually in each confocal plane, using the cell counting tool of Fiji. The data represent mean ± SD. **** p ≤ 0.0001. Two-tailed unpaired Student's t testAberrantly enhanced VEGFR-3 phosphorylation in VE-cadherin-deficient mesenteric LECs of six weeks old mice that had received 4-OHT injections at P2 and P4. Shown are wholemount immunostainings for the antigens shown on the left in color. pVR3, pVEGFR-3, PRX1, PROX1; PEC1, PECAM1. (G) and (I) show a magnification of the area outlined by the white dashed box in (F) and (H). Scale bars = 50 μm. The data are representative for 6 (Cdh5lox/lox) and 5 (Cdh5lox/lox; Prox1-CreERT2) analyzed animals from 2 littersDermal, mesenteric and intestinal tissue pieces of 15 week old control (Cdh5lox/lox) mice were dissociated and total RNA was extracted immediately. For reverse transcription 2.0 µg of total RNA was used for each tissue type. Expression of lymphangiogenic factors VEGF-C and VEGF-D was determined by quantitative real-time (qRT)-PCR using specific TaqMan probes. Samples were measured in triplicate and diagrams are representative for 3 independent experiments. Relative expression (ΔΔCt) of target genes was normalized to the control transcript UBCLoss of VEGFR-3 surface expression on mesenteric LECs growing in cell sheets was associated with concomitant upregulation of VEGFR-2, scale bars = 50 μm. The data are representative for 4 analyzed animals from 2 litters.VR2, VEGFR-2; VR3, VEGFR-3, PRX1, PROX1Expression of the transcriptional co-activators YAP and TAZ was analyzed in mesenteric wholemount preparations 8 weeks after induction of VE-Cadherin deletion at 1 year of age by three doses of Tamoxifen. Respective antigens depicted are indicated on the top of the panels in colour. The highly related molecules YAP and TAZ were both recognized by the antibody used and are therefore collectively abbreviated Y/T. Scale bars = 100 μm
Figure 7  Fig. 7: Loss of VE-cadherin from lymphatic endothelial cells results in increased circumferential actin and a reduced number of focal adhesions. A, B Primary dermal LECs were isolated as described in appendix Fig. S8 A. PdLECs were used for up to four passages and control and VE-cadherin-deleted pdLECs had been cultured for the same number of passages. Cells were seeded at a density of 2.5 x 104 cells on gelatine-coated 15mm glass coverslips and co-stained after 3 days of culture for the actin cytoskeleton (Phalloidin) and either Vinculin (A) or FAK (B) for the visualization of focal adhesions. PROX1 staining in (A) identifies LECs, nuclei in (B) were counterstained with Hoechst. Scale bars correspond to 50 µm. (C, D) Bar diagrams show the number of focal adhesions/cell, which were enumerated using Image J from the Vinculin and FAK stainings shown in (A and B). Data are mean values + S.E.M. derived from three cell lines and 9 viewfields of 256 µm x 256 µm per biological group. *** p ≤ 0.001. Two-tailed unpaired Student's t test.
Figure 8  Fig. 8: Enhanced collective cell migration in VE-cadherin-deficient lymphatic endothelial cells. (A) Collective cell migration of VE-cadherin-deficient and control LECs was assessed in wound scratch assays. LECs were grown up to four passages and seeded at a density of 5x104 cells on fibronectin-coated 8 well µ-chamber slides (growth area 0.22 cm2); scale bar 500 µm (B) The area of the zone denuded from cells is depicted in the curve diagram showing mean values ± SD of three individual experiments conducted in quadruplets. * p ≤ 0.01. Two-tailed unpaired Student's t test. Expanded View Figures - Legends
Figure 1A. Endogenous Cyclin B1-YFP localisation during mitosis live in RPE1 cells (still from Movie EV1).Immunofluorescence images (B) of relative Cyclin B1 and MAD1 levels at unattached and attached kinetochores in cells arrested in STLC.C. Immunofluorescence quantifications (C) of relative Cyclin B1 and MAD1 levels at unattached and attached kinetochores in cells arrested in STLC. Each dot represents a kinetochore, data is from 40 kinetochore pairs (13 cells, max 5 kinetochore pairs/cell).D,E. Quantification of relative kinetochore intensities of Cyclin B1 and MAD1 in nocodazole-arrested cells (noco) treated with the MPS1 inhibitors, AZ-3146 (5μM) or Reversine (500nM), either before (D) or after (E) mitotic entry.F. Immunofluorescence images of LacI-MAD1 and Cyclin B1 in U2OS cells containing a LacO arrays on chromosome 1G. Live imaging of Cyclin B1-mCherry (CycB1-mCh) in LacO-U2OS cells transfected with LacI-MAD1-FL (full length: aa1-718) or various LacI-MAD1 truncations (amino acid numbers indicated).H,I. Immunofluorescence images (H) and quantifications (I) of Cyclin B1 and MAD1 kinetochore levels in control (MAD1-WT) or MAD1β HeLa cells (two independent clones: C13 or C24) treated with nocodazole.J,K. Immunofluorescence images (J) and quantification (K) of Cyclin B1 and MAD1 kinetochore localisation in doxycycline-inducible MAD1α and β knockouts treated with or without dox for 10 days and then arrested in nocodazole. Cells were selected that had full MAD1 knockout in the doxycycline treatment (this constituted approximately 30% of cells).L. Relative kinetochore volumes occupied by Cyclin B1 and MAD1 (relative to CenpC) in nocodazole-arrested MAD1α and MAD1β cells (calculated from experiments shown in (H,I).
Figure 2A. Elution profiles and SDS-PAGE for SEC runs on the indicated column of the Cyclin B1:CDK1 complex (blue profile), MBP-MAD1:MAD2 (red), and their combination (green). Note that the same Cyclin B1:CDK1 elution profile and SDS-PAGE is also displayed as reference in panels D and F to improve clarity. For the same reason, the MBP-MAD1:MAD2 elution profile and SDS-PAGE is also displayed in panels 2A-C. B. Elution profiles and SDS-PAGE for SEC runs on the indicated column of CDK1 (blue), MBP-MAD1:MAD2 (red), and their combination (green). C. Elution profiles and SDS-PAGE for SEC runs on the indicated column of Cyclin B1 (blue), MBP-MAD1:MAD2 (red), and their combination (green). D. Elution profiles and SDS-PAGE for SEC runs of the Cyclin B1:CDK1 complex (blue), MBP-MAD1∆93:MAD2 (green), and their combination (red). F. Elution profiles and SDS-PAGE for SEC runs of Cyclin B1:CDK1 (blue), MBP-MAD13EK:MAD2 (E52K, E53K, and E56K mutations; red), and their combination (green). In A-D, individual potential binding partners were combined at a concentration of 5 µM.
Figure 3A. Western blot analysis of indicated vsv-MAD1-WT or 3EK HeLa clones treated with or without doxycycline for 10 days.B. Immunofluorescence images showing MAD1 and ZW10 kinetochore levels in nocodazole-arrested MAD1-WT-C13 AND 3EK-C14 just after nuclear envelope breakdown (early prometaphase) or later in mitosis when the chromatin is condensed (late prometaphase). Note, that early and late prometaphase was defined based on the level of chromatin condensation.C,D. Relative kinetochore volumes occupied by MAD1 (C) and ZW10 (D) (relative to CenpC) in MAD1-WT and -3EK cells in early and late prometaphase.E. Quantification of MAD1 kinetochore intensity from indicated MAD1-WT and 3EK clones treated as in (B).
Figure 5A. Immunofluorescence images of MAD1 and MAD1-pT716 kinetochore levels in nocodazole-arrested RPE1 cells treated with or without AZ-3146. Scale bars = 5µM.B. Electron micrographs of rotary-shadowed MAD193-718:MAD2 (top row), MBP-MAD1:MAD2 (middle row), and MBP-MAD1:MAD2 in complex with GST-CDK1:Cyclin B1 (bottom row). Scale bar = 50 nm.C. Quantifications (top) and corresponding immunofluorescence images (underneath) of relative kinetochore MAD1 and MAD1-pT716 levels in nocodazole-arrested of MAD1-WT-C14 and MAD1-3EK-C12 cells treated with different doses of AZ-3146 for 30 min. MG132 was included at the time of AZ-3146 addition to prevent mitotic exit. Each dot represents a cell, horizontal lines indicate the median and error bars show the 95% confidence interval. Note, when these vertical bars do not overlap the difference is considered statistically significant at a level of at least p<0.05 (see methods). 30 cells from 3 experiments. Both kinetochore intensity graphs display data that is relative to the WT-C14 untreated controls, which are normalised to 1. The mean level of the normalised controls is indicated by the dotted lines.D. Duration of mitotic arrest in MAD1-WT C14 or MAD1-3EK C12 cells arrested in nocodazole and then treated with indicated concentrations of AZ-3146. Note, the 1.25 µM AZ-3146 data is displayed in Figure 4D, but also included here to allow comparison with other drug doses. Graph shows cumulative mean (±SEM) of 3 experiments, 50 cells per condition per experiment.
Figure 1The heatmap shows the dynamic expression of genes in the SF3A/3B complex (E) and SR family (F) at each indicated differentiation stage. Both heatmaps were row normalized. The heatmaps were scaled with Z-Score using the log2(FPKM) expression of indicated components. n=3 technical replicates.The mRNA expression of splicing regulator SRSF2 and splicing factor PCBP2 during hematopoietic differentiation were measured by RT-qPCR. The ACTB gene was used as a control. Results given are mean ± standard deviation (SD). P-values were determined by an unpaired two-tailed Student's t-test. n ≥ 3 biological replicates.
Figure 2The experimental schematic (upper panel). APLNR+ cells on day 2 were FACS-purified and treated with various dosages of PLB from day 2.5 to 5 during inducing hematopoietic differentiation. On day 5, the generation of CD31+CD34+ EPCs and CD31+CD34+CD73- HEPs were assessed. The representative FACS plots showed the frequency of APLNR+ cells, CD31+CD34+ EPCs and CD31+CD34+CD73- HEPs without or with PLB treatment. The bar graphs show the percentage of CD31+CD34+ EPCs and CD31+CD34+CD73- HEPs without or with PLB treatment.
Figure 3The bar graph represents the percentage of CD31+CD34+ cells from (H). P-values were calculated by one-way ANOVA followed by Tukey's test.The bar graph representing the percentage of CD31+CD34+ cells from (K). P-values were determined by an unpaired two-tailed Student's t-test.
Figure 4The representative FACS plots show the frequency of CD31+CD34+ EPCs in the GFP+ population at day 5 with 1.25 nM PLB supplementation alone or in combination with NUMB_S ectopic expression from day 2.5. The bar graph denotes the percentage of CD31+CD34+ in GFP+ cells as described in (F). P-values were determined by an unpaired two-tailed Student's t-test.
Figure 5On day 5 of hematopoietic differentiation, the inclusion or exclusion of NUMB exon 9 were detected by RT-PCR with 1.25 nM PLB supplementation or SRSF2 exogenous expression alone or their combinational treatment from day 2.5. The bar graph showing the signaling intensity of each specific band from the RT-PCR electropherogram.The top panel depicts the location of specific primers targeting NUMB_S and NUMB_L isoform. The bottom bar graph showing the expression of NUMB_S and NUMB_L in cells on day 5 of differentiation with 1.25 nM PLB supplementation or SRSF2 exogenous expression alone or their combinational treatment from day 2.5 with RT-qPCR.
Figure 6The heatmap plotting the expression of NUMB_S and the key components in NOTCH signaling in day 2-APLNR+ cells, day 5-DMSO treated and day 5-PLB treated cells (2.5 nM), respectively. The NOTCH components were divided into groups of upregulated, downregulated, and unchanged by comparison between DMSO and PLB treated cells. The heatmap was scaled with Z-Score using the log2(FPKM) expression of indicated genes. n=2 technical replicatesThe representative FACS plots indicating the generation of CD31+CD34+ EPCs on day 5 of differentiation with or without HES1 overexpression. DOX was treated from day 2.5 to 5 to induce HES1 overexpression. Statistical analysis of the percentage of CD31+CD34+ EPCs of (H).
Figure 1B In vivo transduction profile of luciferase reporter vectors displaying variants of the enriched library capsid sequence motifs or unmodified wild type AAV2 control capsid. Four weeks after i.v. injection of 5x1010 genomic particles/mouse containing a CMV-luciferase reporter gene, luminescence was measured in the brain and control organs. Data are shown as bars (mean) with plotted individual data points (n = 3 animals/group, age 8-12 weeks).
Figure 2A Luciferase reporter gene vectors displaying the brain-targeted peptide NRGTEWD ("BR1"), unmodified wild type AAV2 capsid, or the previously reported brain-targeting peptide DSPAHPS (PPS). Vectors were intravenously injected into mice (5x1010 genomic particles/mouse). Panels show representative examples of n = 5 animals, age 8-12 weeks per group. Animals were imaged in dorsal (left panel), ventral (second from left panel), and lateral (second from right and right panel) position, 14 days after vector injection.B Close-up imaging of AAV-BR1-treated mice. Mice were imaged in dorsal and lateral position in a different color scheme allowing detailed visualization of the transduced brain in living animals, even as late as at day 264 after vector injection.C Virtual sections : sagittal, coronal, and transaxial (left panels) and three-dimensional reconstruction (right panel) of the luminescence images of a mouse injected with BR1 vector (as in A). Images were obtained by measuring different wavelengths of the emitted light (Living Image software), confirming the brain as exclusive source of luminescence.
Figure 3AAV-BR1 vector harboring the luciferase gene under control of the CAG promoter was administered intravenously (5x1010 genomic particles/mouse, age 8 weeks). Long-term transgene expression was analyzed by in vivo bioluminescence imaging at 16 time points during a 665-day period (n = 2 animals). Original images of analyzed animals (above) and quantification of luminescence in the brain as the region of interest = ROI (bottom).
Figure 4Luciferase activity and vector copy numbers were determined in tissue lysates 14 days after vector administration (5x1010 genomic particles/mouse, age 8-12 weeks).A Vector-mediated luminescence. Transgene expression was measured in AAV-BR1 harboring the luciferase gene under control of the CAG promoter and control vectors (AAV-PPS and wild type rAAV2) in brain and off-target control organs (left panel). Comparison of luminescence in the brain mediated by AAV-BR1 and control vectors (right panel), ****p < 0.0001 (BR1: brain vs. all), ***p = 0.0002 (PPS: heart vs. brain/ muscle), ***p = 0.0001 (PPS: heart vs. lung/ liver/ spleen/ kidney), *p = 0.0101 (WT: heart vs. lung), *p = 0.0120 (WT: heart vs. spleen), *p = 0.0148 (WT: heart vs. kidney), *p = 0.0113 (WT: heart vs. muscle), **p = 0.0011 (Brain: BR1 vs. PPS), ***p = 0.0009 (Brain: BR1 vs. WT).Luciferase activity and vector copy numbers were determined in tissue lysates 14 days after vector administration (5x1010 genomic particles/mouse, age 8-12 weeks).B Biodistribution of AAV-BR1 and control vectors (AAV-PPS and wild type rAAV2) in brain and off-target control organs, excluding spleen (left panel). Genome copy numbers of AAV-BR1 and control vectors (AAV-PPS and wild type rAAV2) in the brain (right panel), ****p < 0.0001 (BR1: brain vs. liver/ kidney/ muscle), ***p = 0.0006 (BR1: brain vs. heart), ***p = 0.0003 (BR1: brain vs. lung), **p = 0.0025 (PPS: kidney vs. muscle), *p = 0.0378 (PPS: kidney vs. lung), *p = 0.0114 (PPS: kidney vs. liver), *****p < 0.0001 (WT: liver vs. all), **p = 0.0028 (Brain: BR1 vs. PPS/ WT).
Figure 5C57BL/6 mice (age 8 weeks) were injected with AAV-BR1 harboring an eGFP reporter gene under control of the CAG promoter. Images show representative examples of n = 6 mice.A Representative images from cerebellum, olfactory bulb, striatum, cerebral cortex, and the spinal cord, 14 days after vector injection. BR1-eGFP-transduced cells (green) were positive for the endothelial marker CD31 (red). Scale bars represent 250 µm.C57BL/6mice (age 8 weeks) were injected with AAV-BR1 harboring an eGFP reporter gene under control of the CAG promoter. Images show representative examples of n = 6 mice.B Higher magnification confocal microscopy images. The endothelial marker CD31 (red) colocalizes with vector-mediated eGFP expression (green). Scale bars represent 50 µm (upper panel) or 10 µm (lower panel).C57BL/6 mice (age 8 weeks) were injected with AAV-BR1 harboring an eGFP reporter gene under control of the CAG promoter. Images show representative examples of n = 6 mice.C CD13 staining of pericytes. The vector-mediated eGFP expression pattern (green) does not colocalize with CD13 (red). Scale bars represent 250 µm (upper panel) or 10 µm (lower panel).C57BL/6 mice (age 8 weeks) were injected with AAV-BR1 harboring an eGFP reporter gene under control of the CAG promoter. Images show representative examples of n = 6 mice.D Aquaporin 4 staining of astrocyte end-feet. The vector-mediated eGFP expression (green) does not colocalize with aquaporin 4 (red). Scale bars represent 100 µm (upper panel) or 10 µm (lower panel).C57BL/6 mice (age 8 weeks) were injected with AAV-BR1 harboring an eGFP reporter gene under control of the CAG promoter. Images show representative examples of n = 6 mice.E Expression of eGFP in primary brain endothelial cells prepared from C57BL/6 mice, 14 days after injection with AAV-BR1-eGFP. Scale bars represent 500 µm (upper panel) or 100 µm (lower panel).