Lin/streptomycin at 37uC in 5 CO2. The transfections were carried out as described for the INS1 23388095 832/13 cells [37], except that the cells were seeded in 24-well plates at a density of 46105 cells. The luciferase reporter assays were performed using the luciferase reporter assay systemElectrophoretic Mobility Shift Assay (EMSA)16107 of INS-1 832/13 cells were harvested for preparation of nuclear extracts. The cells were washed with PBS and resuspended in 1 ml of nuclear extraction buffer I (10 mM HEPES pH7.9, 1.5 mM MgCl2, 10 mM KCl, 0.5 mM DTT and 1x protease inhibitor cocktail (Roche) at 4uC for 1 min. The nuclei were centrifuged at 3,000 g at 4uC for 1 min before resuspended in 100 ml nuclear buffer 2 (20 mM HEPES, pH7.9, 25 (v/v) glycerol, 420 mM NaCl, 1.5 mM MgCl2, 0.2 mM EDTA and 0.2 mM PMSF) and incubated on ice for 5 min. The nuclear lysate was centrifuged at 3,000 g for 5 min at 4uC and the supernatant was kept at 280uC and used for EMSA. The 59-end labeled biotinylated oligonucleotide was synthesized by BioBasic (Canada) and annealed with the unlabelled complementary strand oligonucleotide. The oligonucleotides used in EMSA are listed in Table 3. The DNA-protein binding assay was carried out in 16985061 a 20 ml-reaction mixture containing 1x binding buffer (25 mM HEPES, pH7.9), 25 (v/v) glycerol, 420 mM NaCl, 1.5 mM MgCl2, 10 mM KCl, 0.2 mM EDTA, 0.5 mM DTT and 0.2 mM PMSF, 10 mg of nuclear extract, 2 mg of poly dI-dC and 120 fmole of biotinylated double stranded oligonucleotide at 4uC for 30 min. For supershift assays, 1 mg of anti-Sp1 (sc59), anti-Sp3 (get Dimethylenastron sc-644), anti-USF1 (sc-22) or anti-USF2 (sc-862) polyclonal antibody (SantaCruz Biotech) was included in the binding reaction. The DNA-protein complexes were analyzed byDistal Promoter of the Human Pyruvate CarboxylaseTable 3. Oligonucleotides used in EMSA.Oligonucleotide 278/254 CCAAT-F* 278/254 CCAAT-R 278/254 CCAAT-MuF 278/254 CCAAT-MuR 2340/2315 hP2-F* 2340/2315 hP2-R 2340/2315 hP2-MuF 2340/2315 hP2-MuR *39 labeled with biotin. doi:10.1371/journal.pone.0055139.tSequence (59- 39) GTCTGGGCCAATAGGAAGTCCGTAA TTACGGACTTCCTATTGGCCCAGAC ACGGGAGGGGTTATAGGAAGTCCG CGGACTTCCTATAACCCCTCCGT CACTTCCGCCTATTGCGGGCGTCGG CCGACGCCCGCAATAGGCGGAAGTG CCACAGCCCGGCCTAGGGTCCGGC GCCGGACCCTAGGCCGGGCTGGProbe/competitor Probe/WT competitorMutant competitorProbe/WT competitorMutant competitor5 non-denaturing polyacrylamide gel electrophoresis followed by electroblotting. The bands of DNA-protein interaction were detected using LightShift Chemiluminescent EMSA kit (Pierce). The image was captured using Gel Doc System (GeneTools).Author ContributionsConceived and designed the AN 3199 web experiments: AT PR SJ MJM. Performed the experiments: AT PR. Analyzed the data: AT PR SJ MJM. Contributed reagents/materials/analysis tools: SJ MJM. Wrote the paper: AT PR SJ MJM.AcknowledgmentsThe authors thank Mindy A. Kendrick and Melissa J. Longacre for technical assistance.
The tumor microenvironment plays important roles in the biological behavior of any tumor, which includes the host immune response, tissue oxygen tension, and cancer-associated fibroblasts (CAFs) [1]. Adequate levels of arginine in the extracellular milieu are crucial for T cell proliferation and activity. [2,3] Arginine is one of the semi-essential amino acids and arginine levels are regulated by arginase (ARG), [4] which hydrolyzes arginine to ornithine and urea. There are two isozymes of ARG, ARG1 and ARG2. ARG1, a cytoplasmic enzyme, is expressed mainly in the li.Lin/streptomycin at 37uC in 5 CO2. The transfections were carried out as described for the INS1 23388095 832/13 cells [37], except that the cells were seeded in 24-well plates at a density of 46105 cells. The luciferase reporter assays were performed using the luciferase reporter assay systemElectrophoretic Mobility Shift Assay (EMSA)16107 of INS-1 832/13 cells were harvested for preparation of nuclear extracts. The cells were washed with PBS and resuspended in 1 ml of nuclear extraction buffer I (10 mM HEPES pH7.9, 1.5 mM MgCl2, 10 mM KCl, 0.5 mM DTT and 1x protease inhibitor cocktail (Roche) at 4uC for 1 min. The nuclei were centrifuged at 3,000 g at 4uC for 1 min before resuspended in 100 ml nuclear buffer 2 (20 mM HEPES, pH7.9, 25 (v/v) glycerol, 420 mM NaCl, 1.5 mM MgCl2, 0.2 mM EDTA and 0.2 mM PMSF) and incubated on ice for 5 min. The nuclear lysate was centrifuged at 3,000 g for 5 min at 4uC and the supernatant was kept at 280uC and used for EMSA. The 59-end labeled biotinylated oligonucleotide was synthesized by BioBasic (Canada) and annealed with the unlabelled complementary strand oligonucleotide. The oligonucleotides used in EMSA are listed in Table 3. The DNA-protein binding assay was carried out in 16985061 a 20 ml-reaction mixture containing 1x binding buffer (25 mM HEPES, pH7.9), 25 (v/v) glycerol, 420 mM NaCl, 1.5 mM MgCl2, 10 mM KCl, 0.2 mM EDTA, 0.5 mM DTT and 0.2 mM PMSF, 10 mg of nuclear extract, 2 mg of poly dI-dC and 120 fmole of biotinylated double stranded oligonucleotide at 4uC for 30 min. For supershift assays, 1 mg of anti-Sp1 (sc59), anti-Sp3 (sc-644), anti-USF1 (sc-22) or anti-USF2 (sc-862) polyclonal antibody (SantaCruz Biotech) was included in the binding reaction. The DNA-protein complexes were analyzed byDistal Promoter of the Human Pyruvate CarboxylaseTable 3. Oligonucleotides used in EMSA.Oligonucleotide 278/254 CCAAT-F* 278/254 CCAAT-R 278/254 CCAAT-MuF 278/254 CCAAT-MuR 2340/2315 hP2-F* 2340/2315 hP2-R 2340/2315 hP2-MuF 2340/2315 hP2-MuR *39 labeled with biotin. doi:10.1371/journal.pone.0055139.tSequence (59- 39) GTCTGGGCCAATAGGAAGTCCGTAA TTACGGACTTCCTATTGGCCCAGAC ACGGGAGGGGTTATAGGAAGTCCG CGGACTTCCTATAACCCCTCCGT CACTTCCGCCTATTGCGGGCGTCGG CCGACGCCCGCAATAGGCGGAAGTG CCACAGCCCGGCCTAGGGTCCGGC GCCGGACCCTAGGCCGGGCTGGProbe/competitor Probe/WT competitorMutant competitorProbe/WT competitorMutant competitor5 non-denaturing polyacrylamide gel electrophoresis followed by electroblotting. The bands of DNA-protein interaction were detected using LightShift Chemiluminescent EMSA kit (Pierce). The image was captured using Gel Doc System (GeneTools).Author ContributionsConceived and designed the experiments: AT PR SJ MJM. Performed the experiments: AT PR. Analyzed the data: AT PR SJ MJM. Contributed reagents/materials/analysis tools: SJ MJM. Wrote the paper: AT PR SJ MJM.AcknowledgmentsThe authors thank Mindy A. Kendrick and Melissa J. Longacre for technical assistance.
The tumor microenvironment plays important roles in the biological behavior of any tumor, which includes the host immune response, tissue oxygen tension, and cancer-associated fibroblasts (CAFs) [1]. Adequate levels of arginine in the extracellular milieu are crucial for T cell proliferation and activity. [2,3] Arginine is one of the semi-essential amino acids and arginine levels are regulated by arginase (ARG), [4] which hydrolyzes arginine to ornithine and urea. There are two isozymes of ARG, ARG1 and ARG2. ARG1, a cytoplasmic enzyme, is expressed mainly in the li.