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Mereau, De Rijck et al. Supplementary information A) Supplementary Material & Methods Cell lines and reagents MOLM13, (AML, MLL-AF9+); THP1, (AML, MLL-AF9+); MV4;11 (AML, MLL-AF4+); HL-60, (AML, MLL WT); Jurkat (T-ALL); and Kasumi (AML, AML1-ETO) cell lines were purchased from DSMZ (Braunschweig, Germany). All cells were cultured in RPMI-1640 with glutamine, supplemented with 10% fetal calf serum (FCS) and 1% Penicillin/streptomycin at 37°C and 5% CO2. IL3 independent Ba/F3 cells carrying the FLT3-ITD mutation (Ba/F3 FLT3-ITD) have been described previously 1. 293T cells (ATCC/LGC Standards, Molsheim Cedex France) were grown in Dulbecco's modified Eagle's medium with Glutamax (Gibco, Invitrogen, Merelbeke, Belgium) supplemented with 8% FCS and 50 µg/ml gentamicin (Gibco). Plasmids The pMSCV (Murine Stem Cell Virus) retroviral expression vector encoding for the MLL-AF9 fusion was provided by J. Hess (Ann Arbor), pMSCV-MLL-ENL-neo was provided by Robert Slany (Erlangen). The retroviral transfer plasmid expressing eGFP (pMSCV IRES-eGFP-PGK-Puro) was derived from pLMP (Open Biosystems, Fermentas GmbH, St Leon-Rot, Germany) where the backbone was removed by digestion with SpeI enzyme. The missing part of the PGK sequence was replaced by SpeI digestion of a pMSCV-PKG-Puro vector (Clontech, Saint-Germain en Laye, France) and ligation of this fragment into the modified pLMP plasmid. To create the MSCV plasmid expressing eGFP-LEDGF325-530 (pMSCV eGFP-LEDGF325-530 PGKPuro), eGFP-LEDGF325-530 was amplified from peGFP-LEDGF325-530 IRES Puro 2 using oligo’s DR1 and DR2 (Table 1), digested with BamHI and MfeI and subcloned into pMSCV-PGK-Puro (Clontech, Saint-Germain en Laye, France) digested by BglII and EcoRI. The shRNA- fragment for murine LEDGF/p75 was purchased from Open Biosystems (V2MM_34220) and subcloned from pSMC into the pLMP retroviral vector. To clone the lentiviral transfer plasmids pSFFV-eGFP-I-Puro-WS and pSFFVeGFP-LEDGF325-530-I-Puro-WS expressing eGFP and eGFP-LEDGF325-530 respectively, eGFP-I-Puro and eGFP-LEDGF325-530-I-Puro were amplified by PCR from peGFP-IRES-Puro and peGFP-LEDGF325-530-IRES-Puro 2, respectively with Mereau, De Rijck et al. 1 oligo’s DR3 and DR4 (Table 1). PCR products were digested with BamHI and NheI 3 and sublconed into pSFFV-eGFP-WS-Isa where eGFP was removed through a BamHI/SpeI digestion. To create the LEDGF/p75 knockdown lentiviral transfer plasmid pSFFV-eGFP–I-Puro 2xmi p75 WS, expressing eGFP and a duplicate LEDGF/p75 microRNA cassette, the microRNA cassette was amplified by PCR with oligo’s DR5 and DR6 (Table 1) from pSFFV-eGFP-Ires-tCD34-mirLEDGF digested with SpeI and subcloned into peGFP-IRES-Puro 3 digested with XbaI. The resulting eGFP-IRES-Puro-mirShLEDGF cassette was removed by NheI/BamHI digestion and subcloned into pSFFV-eGFP-d325-2xL3 3 in which the eGFP-LEDGF325-530-2xL3 cassette was removed by XbaI/BamHI digestion. To create the plasmid for eukaryotic expression of HA tagged Menin (pCH SFFV Menin-HA WS), the Menin coding sequence was amplified by PCR from pGEX-Menin (kindly provided by Prof. Carlos Casiano, Loma Linda University, USA) using oligo’s DR7 and DR8, containing the HA-tag coding sequence and digested by BamHI/NheI. This PCR fragment was subcloned into pSFFVeGFP-WS-Isa 3 digested with BamHI/SpeI to remove the eGFP coding sequence. Expression vectors for various eGFP-LEDGF deletion mutants were generated by overlap extension PCR using the LEDGF325-530 sublclone in pBlue Script KS as template. The T3 Reverse was used as common primer to generate the C-terminal deleted mutants and T7 Forward to generate the N-terminal deleted fragments. The smallest fragments were generated using the same strategy and by using the two minimal active mutants identified LEDGF 325-386 and LEDGF424530 as templates. All primers used for the generation of the LEDGF fragments are described in Table 1. The generated LEDGF deletion mutants were then cloned back into pLMP expression vector. To clone the plasmid for eukaryotic expression of tripleflag-tagged (Flag) MLL1-330 a codon optimized synthetic gene was ordered from Life Technologies, Ghent, Belgium. The synthetic gene, MLL1-330 was amplified using oligo’s DR9 and DR10 (Table 1) and digested by SalI and NheI. This PCR product was subsequently cloned into pEGFP-C3 (Clontech, Saint-Germain-en-Laye, France), which was digested by XhoI and XbaI. The plasmid for purification of FlagLEDGF/p75, pCPNatFlag-p75 was described before 4 To clone the plasmid for purification of MLL1-160-GST (pET-20b MLL1-160-GST), GST, PCR amplified with oligo’s DR 11 and DR12 and digested with EcoRI/XhoI was cloned into pET-20b which was digested with EcoRI/XhoI. The resulting plasmid was subsequently digested with NdeI/BamHI and used to insert MLL1-160, which was amplified by PCR Mereau, De Rijck et al. 2 with the oligos DR13 and DR14 (Table 1) from the MLL synthetic gene and digested with NdeI/BamHI. To create the expression plasmid for His-Thioredoxin-Menin (HTrx-Menin), Menin was amplified from pGEX-Menin with oligo’s DR15 and DR16 (Table 1) and cloned into pDONR221 using the gateway system (Life Technologies) following the protocol provided by the manufacturer. Menin was subsequently transferred from the DONR plasmid to pHXGWA 5 using the gateway protocol. The plasmid for MBP-LEDGF325-530 expression was described before 2. All plasmids were sequence verified. Lentiviral and retroviral vector production Lentiviral vector production was performed as described earlier 6. Retroviral vector production was performed as described previously 7. Giemsa cytospin-staining Murine MLL-AF9 leukemic cells were harvested 10 days post-transduction. 5x104 cells were resuspended in 100 µl PBS and spun onto glass slides using a Shandon Cytospin-2 Centrifuge at 500 rpm for 5 min. The slides were air dried and stained with Wright-Giemsa using the Hematek® Stain Pak Hematology Slide Strainer (Bayer HealthCare, Zurich, Switzerland). Apoptosis test Murine MLL-AF9 leukemic cells were harvested 3, 5, 7 and 10 days after puromycin selection and were stained with an Annexin-V antibody (BDBiosciences, #550475) and DAPI (Gibco, Invitrogen; 1/10000) for 15 min at RT following the manufacturer’s protocol. Samples were analyzed on a Cyan ADP Flow Cytometer (Dako Cytomation, Glostrup, Denmark) using Summit software and Flowjo software. Western Blots Whole cell extracts of different cell lines (293T, human AML cells THP1 and the murine hematopoietic cell lines Ba/F3 FLT3-ITD) were made in 1% SDS, separated by 12.5% sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and electroblotted onto polyvinylidene difluoride membranes (Bio-Rad, Nazareth Eke, Belgium). Membranes were blocked with milk powder in PBS-0.1% Tween 20, and detection was carried out using specific antibodies against LEDGF/p75 (Bethyl, Mereau, De Rijck et al. 3 A302-509A), Flag (Sigma, F7425), HA (Abcam, ab9134) or GFP (Abcam, ab6673). Detection was performed using chemiluminescence (ECL+; Amersham) and horseradish peroxidase (HRP)-conjugated secondary antibodies. Co-immunoprecipitation 7x106 293T cells were plated in a 8.5 cm petri dish and transfected with the indicated plasmids (30 µg total) using branched PEI. After 24 hours cells were washed with PBS and lysed with 700 µl lysis buffer (50 mM Tris/HCl, pH7.3, 250 mM NaCl, 0.5% [v/v] Triton X-100, 10% glycerol, Complete Protease Inhibitor Cocktail [Roche, Germany]) for 10 min on ice. The lysate was cleared by centrifugation and the supernatant was incubated with 30 µl ANTI-FLAG® M2-agarose affinity resin (SigmaAldrich) and 10 units DNase (Roche) overnight at 4°C. The beads were collected by centrifugation (30 s, 1800xg, 4°C) and washed 3 times in 600 µl lysis buffer. Immunoprecipitated protein was eluted with 40 μl SDS-PAGE loading buffer and visualized by western blotting. Protein purification Flag-tagged LEDGF/p75 expression and purification was essentially the same as for the non-tagged LEDGF/p75 8. MBP-LEDGF325-530 was purified as described before 21. All other proteins were expressed in E. Coli Rosetta2 (DE3) grown on Lysogeny broth (LB) medium supplemented with 20 mg/ml ampicillin. Bacterial cultures were grown at 37°C for MLL1-160-GST, His-TRX-LEDGF375-386, His-TRX-LEDGF424-435, and His-TRX-ET production and at 28°C for His-TRX-Menin production. Protein expression was induced with 0.5 mM isopropyl--d-1-thiogalactopyranoside (IPTG) at an OD600 of 0.5. H-TRX-LEDGF375-386, H-TRX-LEDGF424-435 and H-TRX-ET cultures were harvested after 1 h. MLL1-160-GST and H-TRX-Menin cultures were harvested after 4 hours. Cells were washed in 20 mL STE buffer (10 mM Tris/HCl pH7.5; 100 mM NaCl, 0.1 mM EDTA), and pellets were stored at −20°C. For purification of HTRX tagged proteins, cell pellets were resuspended in lysis buffer (50 mM Tris–HCl pH7.5; 150 mM NaCl, 20 mM imidazole, 1 mM PMSF and 0.1 U/ml DNase) and lysed by sonication. The lysate was clarified by centrifugation at 19800×g for 30 minutes at 4°C and subjected to affinity chromatography using His-Select Nickel Affinity Gel (Sigma) equilibrated with wash buffer (50 mM Tris/HCl pH7.5; 150 mM NaCl, 20 mM imidazole). His-tagged proteins were eluted with wash buffer containing 250 mM Mereau, De Rijck et al. 4 imidazole. Purification of MLL1-160-GST was carried out by affinity chromatography on Glutathione Sepharose-4 Fast Flow (GE Healthcare, Fairfield, CT). The resin was equilibrated with wash buffer (50 mM Tris/HCl pH7.5, 150 mM NaCl) and GSTtagged proteins were eluted in wash buffer supplemented with 25 mM Glutathione (GSH). Fractions were analyzed by SDS-PAGE for protein content. Peak fractions were dialyzed against 100x excess 20 mM Tris/HCl pH7.5, 150 mM NaCl, 10%(v/v) glycerol at 4°C over night. H-TRX-Menin was concentrated using Amicon Ultra Concentrators (Millipore). AlphaScreen AlphaScreen measurements were performed in a final volume of 25 µL in 384-well Optiwell microtiter plates (PerkinElmer). All components were diluted to the indicated concentrations in assay buffer (25 mM Tris pH7.4, 150 mM NaCl, 1 mM DTT, 0.1% (v/v) Tween-20 and 0.1% (w/v) Bovine Serum Albumin (BSA). Optimal binding concentrations for MLL-Menin, Menin-LEDGF/p75 and LEDGF/p75-MLL proteins were determined in cross-titration experiments. For apparent Kd determinations, MLL1-160-GST wild type and/or its mutants were titrated against 0.3 nM FlagLEDGF/p75 or 4 nM H-TRX-Menin. For IC50 determinations, MBP-LEDGF325-530 and LEDGF derived peptides (untagged or tagged with H-TRX) were titrated against 10 nM MLL1-160-GST and 0.3 nM Flag-LEDGF/p75. After addition of proteins, peptides and/or compounds, the plate was pre-incubated for 1 h at room temperature (RT). 20 µg/mL Glutathione donor and anti-Flag or Ni2+-chelate acceptor beads (PerkinElmer) were added, bringing the final volume to 25 µL. After 1 h of incubation at RT, the plate was analyzed on an EnVision Multi-label Reader in AlphaScreen mode (PerkinElmer). Results were analyzed in Prism 5.0 (GraphPad software) after nonlinear regression with the appropriate equations: one-site specific binding, taking ligand depletion into account for the apparent Kd measurements and sigmoidal doseresponse with variable slope for the IC50 determination. Peptides Peptides (> 95% purity, HPLC) were purchased from PeptideSynthetics, Hampshire, UK. LEDGF424-435; KNMFLVGEGDSV, LEDGF375-386; EALDELASLQVT. Mereau, De Rijck et al. 5 Supplementary Table 1: Oligo-primers used in this study Oligo 410-530 Forward 424-530 Forward 450-530 Forward pBlueScript II SK T3 Reverse pBlueScript II SK T7 Forward 325-409 Reverse 325-386 Reverse 366-386 Forward 375-386 Forward 424-449 Reverse 424-435 Reverse Sequence 5'-3' TTTGGATCCATGGTGAGCAAGGGCGAGGA GGGCAATTGCTAGTTATCTAGTGTAG CATATTGGATCCATGGTGAGCAAGGGCGAGGAG AAAGCTAGCTCAGGCACCGGGCTTG TTTTACTAGTACTAGCGCTACCGGACTCAG TTTTACTAGTCAACGCGTCCCGGTGGATCC AAAGGATCC ATGGGGCTGAAGGCCGCCC AAAAGCTAGCTCACGCGTAGTCCGGTACGTCGTACGGGTAAG CAGCAGCGAGGCCTTTGCGCTGCCGC TTTTGTCGACCTCAAGCTTGCGCACAGCTGTCGGTG TTTTGCTAGCTTA GACTTTCTGGGGCTTTTCC TTTTGAATTCGGCCTGAACGATATTTTTGAAGCGCAGAAAATTG AATGGCATGAAGTCGAC TCCCCTATACTAGGTTATTGGAAAATTAAG CCCCCTCGAG CTA ATCCGATTTTGGAGGATGGTC TTTTCATATG GCACATAGCTGTCGTTGGCG CCCC GGATCC TCGCACTCTGACTTCTTCATCTGAG GGGGACAAGTTTGTACAAAAAAGCAGGCTTAGGGCTGAAGGC CGCCCAG GGGGACCACTTTGTACAAGAAAGCTGGGTCTAGAGGCCTTTG CGCTGCCGC GCAGTCTCGAGCAGGTAATCATGGAAAAGTCTAC GCAGTCTCGAGAAGAACATGTTCTTGGTTGGTG GCAGTCTCGAGCATGAGGAAGCGAATAAAACC GGTTGGCCCTCAAAAGGG TAATACGACTCACTATAGGGC GTACGGCGATTCAAAGTTAGTTGACAATTGATCG TGTGACCTGAAGTGAAGCAAGTGACAATTGATCG GCAGTCTCGAGGATAATCTTGATGTGAACAGATGCAAT GCAGTCTCGAGGAGGCCTTGGATGAACTTGCTTCA CTGTCTTTGTTCAGCAAGAGATTATTGACAATTGATCG CACGGAATCTTCACCAACTGACAATTGATCG RT-quantitative PCR primers mouse HOXA9 forward mouse HOXA9 reverse mouse GAPDH forward mouse GAPDH reverse Sequence 5'-3 GGTTCTCCTCCAGTTGATAGAGA GAGCGAGCATGTAGCCAGTTG ATGACATCAAGAAGGTGGTG CATACCAGGAAATGAGCTTG DR1 DR2 DR3 DR4 DR5 DR6 DR7 DR8 DR9 DR10 DR11 DR12 DR13 DR14 DR15 DR16 Mereau, De Rijck et al. 6 B) Supplementary Figures Supplementary Figure S1 The anti-leukemic potential of LEDGF325-530 expression in MLL-AF9 transformed hematopoietic cells is maintained upon replating. (A) Colony-forming units (CFU) per 104 MLL-AF9 murine transformed cells expressing eGFP-LEDGF325-530 or eGFP (set to 100%). Cells were flow-sorted and 104 cells were plated in methylcellulose. Seven days later cells were harvested and 10 4 cells were replated for a 2nd round. (B) Hoxa9 mRNA expression levels were assessed by quantitative RT-PCR after the 1st and 2nd round in methylcellulose from the experiment described in A). The expression levels were normalized to Gapdh and the eGFP control (set to 100%). Error bars represent the standard deviations of two independent experiments. Mereau, De Rijck et al. 7 Supplementary Figure S2 Expression of LEDGF/p75 or derived fragments in THP1 cells. (A) THP1 cells were transduced with lentiviral vectors expressing the indicated eGFP fused LEDGF/p75 fragments. Fragments were detected with an eGFP antibody. Equal loading was controlled with an anti-tubuline antibody (-Tub). (B) Knockdown (KD) of LEDGF/p75 upon transduction with a lentiviral vector expressing a LEDGF/p75 shRNA was quantified by Q-RT-PCR and normalized to RNaseP mRNA. Error bars indicate standard deviations of triplicate measurements. Mereau, De Rijck et al. 8 Supplementary Figure S3 Validation of the Alphascreen assays used in this study. (A) Coomassie stained gel of recombinant proteins used in this study. (B) Direct interaction of MLL with Menin. Titration of MLL1-160GST or the F9A mutant against 5 nM H-TRX-Menin in AlphaScreen. Error bars represent the standard deviation of triplicate datapoints. (C) Inhibition of the MLL-Menin interaction by small molecules. 4 nM H-TRX-Menin and 10 nM MLL1-160-GST were preincubated in AlphaScreen. The interaction was inhibited by adding different concentrations of the indicated small molecules. Error bars represent the standard deviation of triplicate datapoints. (D) Direct interaction of Menin and MLL with LEDGF/p75. Titration of H-TRX-Menin and MLL1-160-GST or the F129A, R130A, E135Q triple mutant against 0.3 nM Flag-LEDGF/p75 in AlphaScreen. Error bars represent the standard deviation calculated from 3 independent experiments performed in triplicate. Mereau, De Rijck et al. 9 Supplementary Figure S4 Determination of the minimal MLL/menin interaction domain on LEDGF/p75. (A) Schematic representation of LEDGF/p75 and the derived deletion mutants of eGFP-LEDGF325-530 used for screening. PWWP: Pro-Trp-Trp-Pro chromatin binding domain; NLS: Nuclear localization signal; IBD: Integrase binding domain. The numbers refer to amino acids of the reference sequence: GenBank accession number, NP_001121689.1. (B) Colony-forming units (CFU) per 2.103 plated MLL-AF9 murine transformed cells in the presence of puromycin. Cells were transduced to express the eGFPLEDGF deletion mutants or, as controls, full-length eGFP-LEDGF325-530 or eGFP (set to 100%). Error bars represent standard deviations of a duplicate experiment. Mereau, De Rijck et al. 10 Supplementary Figure S5 Western Blot analysis of BAF3 cells transduced with MSCV derived vectors expressing eGFP, eGFP-LEDGF325-530, eGFP-LEDGF325-386, eGFP-LEDGF424-530, eGFP-LEDGF375-386 or eGFP- LEDGF424-435. Proteins were detected using an eGFP antibody. Equal loading was controlled with an -tubuline antibody (α-Tub). Mereau, De Rijck et al. 11 Supplementary Figure S6 JURKAT 2400 2200 2000 1800 1600 1400 1200 1000 800 600 400 200 0 Number of cells (X103) / ml Number of cells (X103) / ml Control (eGFP) eGFP eGFP-LEDGF325-530 eGFP-d325 eGFP-LEDGF375-386 eGFP-375 eGFP-LEDGF424-435 eGFP-424 180 Control (eGFP) eGFP 160 eGFP-LEDGF325-530 eGFP-d325 140 eGFP-LEDGF375-386 eGFP-375 120 eGFP-LEDGF424-435 eGFP-424 100 80 60 40 20 0 1 C KASUMI B 2 3 4 5 Time (days) 6 7 D HL60 4500 4000 Control (eGFP) eGFP (control) 3500 eGFP-LEDGF LEDGF 325-530 325-530 3000 eGFP-LEDGF LEDGF 375-386 375-386 2500 eGFP-LEDGF LEDGF 424-435 424-435 2000 1500 1000 500 0 1 2 3 4 Time (days) 1 Number of cells (X103) / ml Number of cells (X103) / ml A 5 6 7 2 3 4 5 Time (days) 6 7 MV4;11 1800 Control (eGFP) eGFP (control) 1600 eGFP-LEDGF LEDGF 325-530325-530 1400 eGFP-LEDGF LEDGF 375-386375-386 1200 eGFP-LEDGF LEDGF 424-435424-435 1000 800 600 400 200 0 1 2 3 4 5 Time (days) 6 7 Expression of the LEDGF/p75 fragments significantly impairs growth of MLL-fusion positive MV4;11 cells but not of other acute human acute leukemia cell lines. (A-D) Cell proliferation of Jurkat (T-ALL), Kasumi (AML1-ETO+; AML), HL-60 (c-myc amplification; AML) and MV4;11 (MLLAF4+; AML) cells, transduced with lentiviral vectors expressing the indicated eGFP fused LEDGF/p75 fragments. Error bars represent the standard deviation of two independent experiments. Mereau, De Rijck et al. 12 Supplementary Figure S7 A B Control (eGFP) LEDGF325-530 LEDGF375-386 LEDGF424-435 80 70 % of cells 60 50 40 30 20 10 3 days Living 5 days 7 days Early Apoptosis 5 43 4- 42 5 43 4- e DG GFP LE F3 DG 25-5 3 LE F3 0 DG 75-3 F 86 LE LE 42 e DG GFP LE F3 DG 25-5 3 LE F3 0 DG 75-3 F 86 5 43 4- 42 e DG GFP LE F3 DG 25-5 3 LE F3 0 DG 75-3 F 86 LE 5 43 4- LE 42 e DG GFP LE F3 DG 25-5 3 LE F3 0 DG 75-3 F 86 0 10 days Late apoptosis/Necrosis Expression of eGFP fused LEDGF-fragments induced morphological changes in MLL-AF9 murine cells without increasing apoptosis. (A) Representative Wright-Giemsa-stained cytospin preparation of MLL-AF9 murine leukemic cells 10 days after transduction with eGFP-LEDGF325-530, eGFP-LEDGF375-386 or eGFP-LEDGF424-435 vs. vector control, selected in puromycin. Cells were visualized with an Olympus (Tokyo, Japan) BX61 microscope magnification 60X (Olympus UPlanApo 60X/1,35 NA oil) and pictures were acquired with Cell^P software and ColorviewIII imaging system (Olympus). For each picture, the black scale bare in the bottom left is representative of 20 µm. (B) Evaluation of the proportion of MLL-AF9 cells expressing eGFP fused LEDGF fragments or eGFP control with the living (Annexin-V-/DAPI-), early apoptotic (Annexin-V+/DAPI-) and late apoptotic /necrotic (Annexin-V+/DAPI+) cell fractions. Cells were grown in the presence of puromycin (2g/ml) and analyzed at the indicated time points. Mereau, De Rijck et al. 13 Supplementary Figure S8 Cartoon representation of the published MLL/Menin-IBD co-crystal structure 10. 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