EMBO/SourceData huggingface dataset:
Figure 4(A) Representative confocal images taken at 60 min after admixture of 2 mM GTP and 10 µM Alexa-Fluor647- or Alexa-Fluor488-hGBP1F to formaldehyde fixed gram-negative and gram-positive bacteria expressing GFP (S. enterica Typhimurium [ST], L. monocytogenes [Lm]), or RFP (S. flexneri [Sf], uropathogenic E. coli [UPEC]), or dsRed (L. pneumophila [Lp], S. aureus [Sa]).(B) (Left panel) Confocal time-lapse microscopy frames of Alexa-Fluor488-LPS-O55:B5 after addition of 5 µM Alexa-Fluor647-hGBP1F supplemented with 2 mM GTP. (Right panel) Confocal images taken of 5 µM Alexa-Fluor488-LPS-O55:B5 20 min after addition of 5 µM Alexa-Fluor647-hGBP1F or -hGBP1FR48A supplemented with 2 mM GTP. Graphs depict average aggregate area of Alexa-Fluor488-LPS-O55:B5 supplemented with 2 mM GTP and 5 µM of the indicated hGBP1 variant. Mean area ± SEM of combined data from three independent experiments. Significance was determined by one-way ANOVA with Tukey's multiple comparison test.. n.s., not significant; ***, P ≤ 0.001; ****, P ≤ 0.0001.(C) Polymerization of 5 µM hGBP1F induced by addition of 2 mM GTP in the presence and absence of 5 µM LPS-O55:B5 was monitored by absorption spectroscopy at 350 nm. The absorbance signal was superimposed with nucleotide composition of the same solution analyzed at defined time points. Maximal hydrolysis rates (turnover numbers) were determined for hGBP1F variants in the presence and absence of 5 µM LPS-O55:B5. Graphs show mean turnover numbers ± SEM of combined data from at least three independent experiments. Significance was determined by two-way ANOVA with Tukey's multiple comparison test. n.s., not significant; ***, P ≤ 0.001; ****, P ≤ 0.0001.(D) Formaldehyde fixed GFP+ S. flexneri supplemented with varying LPS-O55:B5 concentrations were mixed with 5 µM hGBP1F and 2 mM GTP. After 60 min hGBP1F-enclosed S. flexneri were quantified. Combined data from three independent experiments are shown as mean ± SEM. Significance was determined by one-way ANOVA with Tukey's multiple comparison test. ****, P ≤ 0.0001.(E) Confocal images of formaldehyde fixed GFP-, RFP-, or dsRed-expressing gram-negative bacteria 60 min after addition of 5 µM Alexa-Fluor647- or Alexa-Fluor488-hGBP1F and 2 mM GTP in the presence and absence of 100 µM LPS-O55:B5. After 60 min hGBP1F-enclosed gram-negative bacteria were quantified. Combined data from three independent experiments are shown as mean ± SEM. Significance was determined by two-way ANOVA with Tukey's multiple comparison test. ****, P ≤ 0.0001.
Figure 5(B) Time-lapse microscopy of fixed GFP+ co-isogenic S. flexneri wild type and rfaL mutant after adding 10 µM Alexa-Fluor647-hGBP1F and 2 mM GTP. Bacteria bound by hGBP1F at 5 min and hGBP1F-enclosed bacteria after 60 min were quantified. Combined data from three independent experiments are shown as mean ± SEM. Significance was determined by unpaired t-tests, two-tailed. n.s., not significant; ****, P ≤ 0.0001.(C) Scanning-electron micrographs of live wild type and rfaL mutant strains incubated with no protein or with 5 µM of hGBP1F in the presence of 2 mM GTP for 4 min. Arrowheads point to unattached hGBP1 polymers, arrows point to hGBP1 polymers attached to bacteria, and asterisks mark polymeric structures that appear to fuse with bacterial surfaces(E) Confocal images of formaldehyde fixed, co-isogenic GFP+ wild type and mutant S. flexneri strains harboring rfb regions of E. coli serotypes O8 and O25 after 60 min of incubation time in the presence of 10 µM Alexa-Fluor647-hGBP1F and 2 mM GTP.
Figure 6(A) Following incubation for 1.5 h with buffer in the absence or presence of 10 µM hGBP1F and 5 mM GTP, live bacteria were treated with antibiotics (2.5 µg/ml PMB or 5 mg/ml lysozyme) for 30 min or left untreated. The number of viable bacteria was subsequently determined by colony forming unit (CFU) counts. Graphs show mean CFUs ± SEM of combined data from at least three independent experiments. Significance was determined by two-way ANOVA with Tukey's multiple comparison test. n.s., not significant; ****, P ≤ 0.0001.(B) Formaldehyde fixed RFP+ UPEC were mixed with 10 µM Alexa-Fluor488-hGBP1F or -hGBP1FR584-586A supplemented with 2 mM GTP. Following 60 min of incubation hGBP1F-enclosed UPEC were quantified. Graphs depict mean ± SEM of combined data from three independent experiments. Significance was determined by unpaired t-test, two-tailed. ****, P ≤ 0.0001.(C) Formaldehyde fixed RFP+ UPEC were mixed with 10 µM Alexa-Fluor488-hGBP1F or -hGBP1FR584-586A and 2 mM GTP. Samples were fixed after 60 min incubation and stained with an antibody against the inner core/ lipid A fragment of E. coli LPS (anti-LPS). The frequency of anti-LPS stained UPEC was quantified. Graphs show mean ± SEM of combined data from three independent experiments. Significance was determined by two-way ANOVA with Tukey's multiple comparison test. n.s., not significant; ****, P ≤ 0.0001.(D) IFNγ-primed wild type and hGBP1-KO HeLa cells stably expressing inactive mutant YFP-Caspase-4C258S were infected with either cytosol-entering S. enterica Typhimurium mutant ΔsifA (MOI = 25) or with S. flexneri ΔospC3ΔipaH9.8 (MOI = 6), a mutant strain lacking Caspase-4 antagonist OspC3 as well as hGBP1 antagonist IpaH9.8. Cells were fixed at 4 hpi (ST ΔsifA) or at 2 hpi (Sf ΔospC3ΔipaH9.8) and stained for endogenous hGBP1. YFP-Caspase-4C258S associated bacteria were quantified and mean ± SEM of combined data from three independent experiments are shown. Significance was determined by two-way ANOVA with Tukey's multiple comparison test. ****, P ≤ 0.0001.
Figure 1(B) Starvation-induced autophagosomes (AP) and autolysosomes (AL) in the fat body (the functional analogue of the liver) of a fruit fly larva. Note that APs contain intact cytoplasm, whereas the contents of ALs show various stages of degradation.(C) Liver cells of starved mice carrying a fluorescently tagged LC3 transgene, labeling cup-shaped and ring-shaped structures that correspond to IMs and autophagosomes, respectively. Images courtesy of Ryan Scott (B) and Dr. Noboru Mizushima (C).
Figure 1(A) Northern blot experiments show the expression of RsaI during growth phase in the HG001 strain in MHB medium with or without the addition of 1,5 g/L of D-glucose. Glucose was added either at the beginning of growth (+ glucose, left panel) or after 3h of growth (right panel).(B) Northern blot experiment shows the expression of RsaI during growth phase in the HG001, ∆ccpA mutant strain, and ∆codY mutant strain, in MHB medium with (+) or without (-) the addition of 1,5 g/L of D-glucose.(C) Northern blot experiment shows the expression of RsaI in the HG001 and ∆ccpA mutant strains. Total RNA was prepared after 2, 3, 4, 5 and 6h of culture in BHI medium at 37°C.(D) Northern blot analysis of RsaI in the HG001 strain grown in MHB medium with or without the addition of 1 g/L of glucose, fructose or xylose. For all the experiments, loading controls were done using the expression of 5S rRNA (5S) as revealed after hybridization of the membranes with a specific probe. However for these controls, we used aliquots of the same RNA preparations but the migration of the samples was performed in parallel to the experiments on a separate agarose gel because RsaI and 5S rRNA have very similar sizes.
Figure 2(B) Gel retardation assays show the formation of the complex between RsaI and icaR, glcU_2 and fn3K mRNAs. The 5' end-labeled wild-type RsaI (RsaI), RsaI mutant 3 (RsaI mut3, deletion of the two G-track motifs), and RsaI mutant 4 (RsaI mut4, deletion of the C/U rich unpaired interhelical region) were incubated with increasing concentrations of mRNAs: lane 1, 0 nM; lane 2, 25 nM; lane 3, 50 nM; lane 4, 100 nM and lane 5, 200 nM. Below the gels, the predicted interactions between RsaI and its targets are shown. Translation start codons are in green and SD is for Shine Dalgarno sequence. Graphs represented the % of complex formed between either RsaI or its two mutant forms (RsaI mut3 and RsaI mut4) and the target mRNA (icaR, glcU_2, fn3K) as the function of mRNA concentrations.(C) Gel retardation assays show the formation of the complex between RsaI and RsaG. The 5' end-labeled wild-type RsaI (RsaI), RsaI mutant 2 (RsaI mut2), RsaI mutant 4 (RsaI mut4), and RsaI mutant 1 (RsaI mut1) were incubated with increasing concentrations of RsaG given in nM on the top of the autoradiographies.
Figure 3(A) Toe-print assays showing the effect of RsaI on the formation of the ribosomal initiation complex of glcU_2 and fn3K mRNAs, respectively. Lane 1 : incubation control of mRNA alone; lane 2 : incubation control of mRNA with 30S subunits; lane 3: incubation control of mRNA with RsaI; lane 4 : formation of the ribosomal initiation complex containing mRNA, 30S and the initiator tRNAfMet (tRNAi); lanes 5 to 9 : formation of the initiation complex in the presence of increasing concentrations of RsaI, respectively : 50 nM (lane 5), 100 nM (lane 6), 150 nM (lane 7), 300 nM (lane 8), and 400 nM (lane 9). Lanes T, A, C, G: sequencing ladders. The Shine and Dalgarno (SD) sequence, the start site of translation (START) and the toe-printing signals (+16) are indicated. At the bottom of the gels are shown the predicted interactions between RsaI and its targets. Translation start codons are in green, and the Shine and Dalgarno (SD) sequence is underlined, the arrowheads depict the toe-printing signals.(B) The β-galactosidase activity (Miller Units) has been measured from various fusions expressed from a plasmid which also carries rsaI gene under its own promoter: PrpoB::glcU::lacZ::rsaI, PrpoB::fn3K::lacZ::rsaI, PrpoB::treB::lacZ::rsaI, PrpoB::HG001_1242::lacZ::rsaI, and PrpoB::HG001_2520::lacZ::rsaI expressed in the mutant strain HG001-∆rsaI. The same constructs were made in the absence of rsaI gene. For the fn3K-lacZ fusion, we also used an additional construct PrpoB::fn3K::lacZ::rsaImut4 expressing both the fusion FN3K-LacZ protein and RsaI mut4. The β-galactosidase activity was normalized for bacterial density and the results represented the mean of four independent experiments. The error bars are standard deviations and the statistical significance was determined using the Student's t-test. * p < 0.05, ** p < 0.005, *** p < 0.0005, **** p < 0.0001, ns is for not significant.
Figure 4(B) Gel retardation assays show the formation of the complex between RsaI and icaR full length, icaR SUBST, icaR-5'UTR, and icaR-3'UTR. The 5' end-labeled of RsaI was incubated with increasing concentrations of the various mRNAs. UTR is for untranslated region, SUBST stands for the substitution of UCCCCUG sequence by AGGGGAC. This mutation, which is located in the 3'UTR of icaR, significantly destabilizes the long-range interaction, and enhances icaR translation. Lane C represents binding between radiolabelled RsaI and full-length icaR mRNA (50 nM). Due to the rather short migration of the gel, the full-length mRNA is still observed in the pocket.(C) In vivo effect of RsaI on PIA-PNAG synthesis in the S. aureus wild-type (WT) 132 strain, the ∆rsaI mutant, and the strain carrying a deletion of icaR 3'UTR (∆3'UTR). This last mutant strain has been transformed with the pES plasmids expressing rsaI or rsaI mut5. The PIA-PNAG exopolysaccharide biosynthesis was quantified using dot-blot assays. Serial dilutions (1/5) of the samples were spotted onto nitrocellulose membranes and PIA-PNAG production was detected with specific anti-PIA-PNAG antibodies. RsaI was detected in the same samples by Northern blot using a probe directed against RsaI. Ethidium bromide staining of rRNA was used as loading controls of the same gel.
Figure 5(A) Ternary complex formation between RsaI, various mRNAs (glcU_2, HG001_00942 and HG001_1242), and RsaG. The 5'-end labeled RsaI was incubated with increasing concentrations of the target mRNA alone or in the presence of 50 nM of RsaG. The various complexes are notified on the sides of the autoradiographies.(B) RsaG does not form stable complexes with glcU_2 and HG001_01242. Binding assays were done in the presence of 5' end-labeled RsaG and either cold RsaI (300 nM) or increasing concentrations of glcU_2 and HG001_01242.(C) Measurements of the half-lives of RsaI and RsaG in HG001-∆rsaG or HG001-∆rsaI mutant strains using Northern blot experiments. The cells were treated with rifampicin at 4h of growth and total RNAs were extracted after 2, 4, 8, 15, 30 and 60 min at 37°C in BHI. 5S rRNA was probed to quantify the yield of RNAs in each lane using the same samples, which were however run on two different gels. Calculated half-lives are shown beneath the autoradiographies and are the average of 2 experiments. The data were normalized to 5S rRNA.
Figure 1B Hops−/− mouse genotyping and protein expression. Genotyping by PCR using genomic DNA showed a 242bp band for wild type (Hops+/+) allele and a 331bp band for mutant (Hops−/−) allele. NTC is Null Template Control (left panel). Genotyping by real time PCR confirmed the absence of Hops mRNA in Hops−/− mice (middle panel). Protein extracts from Hops+/+ and Hops−/− MEFs were analysed by Western Blot using anti-HOPS antibody and anti-α-tubulin antibody as loading control (right panel). Data information: in B data are presented as mean ±SD.C Offspring distribution. Different HOPS genotypes at weaning age (approximately postnatal day 21) from crosses between homozygous knockout mice males and heterozygous females (n=1525 pups). Data information: In C the χ2 test was performed to determine significant differences between the expected and observed ratios of Hops−/− to Hops+/− mice. P < 0.001, by two tailed Student's t-test.
Figure 2A Reduced caspase-3 activation in Hops−/− mice upon apoptotic stimulus. Hops+/+ and Hops−/− mice were treated with etoposide for the indicated times and thymus, spleen, testis and liver were harvested and Tissue-Tek® O.C.T. embedded. Sections were immunostained with anti-cleaved caspase-3 antibody followed by appropriate secondary antibody labelling (green). The graphs display the relative positive cells number. Scale bars, 10µm. Data information: all the experiments were performed three times in three different mice per condition and a representative example is shown. In A data are presented as mean ±SD. ** P < 0.01; *** P < 0.001, by two tailed Student's t-test.B HOPS affects p53 increase after stress in vivo. Whole-cell homogenates from organs, were immediately prepared and immunoblotted with antibodies to detect p53 and GAPDH. The p53 levels were semi-quantified using GAPDH as loading control and relative p53 levels at time 0 were assumed as 1. Data information: all the experiments were performed three times in three different mice per condition and a representative example is shown. In B data are presented as mean ±SD. ** P < 0.01; *** P < 0.001, by two tailed Student's t-test.
Figure 3A Thymocytes from Hops+/+ and Hops−/− mice were treated with dexamethasone (Dex) and the apoptotic cells were measured by flow cytometry. The flow cytometry analysis plots are shown on the left and the data represented as a histogram on the right. Data information: the experiments were performed three times in primary cells from three different mice per condition. In A data are presented as mean ±SD. * P < 0.05; ** P < 0.01; *** P < 0.001, by two tailed Student's t-test.B HOPS was pivotal for apoptosis induction. Hops+/+ and Hops−/− MEFs were subjected to etoposide (Eto) and apoptosis was analysed by flow cytometry (left) and showed as a graph (right). Data information: the experiments were performed three times in primary cells from three different mice per condition. The experiments in MEFs were performed three times. Representative panels are shown. In data are presented as mean ±SD. * P < 0.05; ** P < 0.01; *** P < 0.001, by two tailed Student's t-test.C HOPS overexpression in MEFs promotes apoptosis. Hops+/+ and Hops−/− MEFs were transiently transfected with an empty vector (pEGFP-N1) or with a Hops encoding vector (pEGFP-N1-Hops). The apoptotic cells were measured by flow cytometry (left) on the GFP positive and negative populations and showed as a graph (right). Data information: the experiments were performed three times in primary cells from three different mice per condition. The experiments in MEFs were performed three times. Representative panels are shown. In C data are presented as mean ±SD. * P < 0.05; ** P < 0.01; *** P < 0.001, by two tailed Student's t-test.D HOPS affects p53 levels following stress in vitro. Hops+/+ and Hops−/− MEFs were treated with etoposide and harvested at the indicated time points. The p53 protein levels were semi-quantified using α-tubulin as loading control and relative p53 levels at 0 µM dosage were assumed as 1. Data information: the experiments were performed three times in primary cells from three different mice per condition. The experiments in MEFs were performed three times. Representative panels are shown.
Figure 4A HOPS loss and p53 half-life. Hops+/+ and Hops−/− MEFs untransfected or transfected with HOPS, were analysed by immunoblotting following cycloheximide treatment for the indicated time (left panel). The p53 protein levels were semi-quantified using GAPDH as loading control and relative p53 levels at time 0 were assumed as 100% (right panel). Data information: all the experiments in MEFs were performed three times. Representative panels are shown. In A data are presented as mean ±SD.B p19Arf-independent HOPS control of p53 half-life. p19Arf−/− MEFs untransfected (CTRL), transfected with empty vector (pSGV) or HOPS were treated with cycloheximide for the indicated times and subjected to immunoblot analysis with anti-p53, anti-HOPS and anti-GAPDH antibodies (left panel). The p53 protein levels were semi-quantified as above (right panel). Data information: all the experiments in MEFs were performed three times. Representative panels are shown. In B data are presented as mean ±SD.C HOPS and p53 ubiquitination. p53, HDM2, His-tagged ubiquitin were co-expressed in H1299 cells with HOPS or HOPS-G176A or HOPS-K126A mutants and treated with MG132. p53 ubiquitination rate was evaluated by elution using Ni2+-NTA His-bind resin followed by immunoblotting with anti-p53 and the indicated antibodies.D HOPS depletion and HOPS-G176A mutant affect p53 ubiquitination. Hops+/+ and Hops−/− MEFs untransfected and Hops−/− MEFs transfected with HOPS or HOPS-G176A mutant were co-expressed with p53, HDM2 and His-tagged ubiquitin. Cells were treated with MG132 and the ubiquitinated p53 fraction was recovered as above. Immunodetection of ubiquitinated p53 was performed using anti-p53 antibody and the samples were tested with the indicated antibodies. Data information: all the experiments in MEFs were performed three times. Representative panels are shown.E HOPS-G176A mutant ability to stabilize p53. Hops−/− MEFs were transfected with HOPS-G176A, subjected to cycloheximide treatment for the indicated times and analysed by immunoblotting using the indicated antibodies. Data information: all the experiments in MEFs were performed three times. Representative panels are shown.
Figure 5A Protein binding in RKO cells. PLA showed HOPS/p53 interaction with or without etoposide treatment at the indicated time. Red spots showed a single interaction. DNA counterstaining was performed with DAPI. α-Tubulin-FITC antibody was used to identify the cellular edge. Background control was performed according to the manufacturer's instruction. Scale bars, 10µm. The graph represents the binding increase. Non treated cells binding was assumed as 1. Data information: all the experiments were performed three times, and representative examples are shown. In A data are presented as mean ±SD.B Biochemical analysis of nuclear-cytoplasmic protein distribution. RKO cells were treated with etoposide, collected after 2 and 4 hours and processed to obtain nuclear and cytoplasmic fractions. Aliquots relative to the same cell number per fraction were immunoblotted using anti-HOPS and anti-p53 antibodies. GAPDH and Lamin B1 are purity controls of cytoplasmic and nuclear fraction respectively.C HOPS and p53 binding in cytoplasm following apoptosis induction. RKO cells untreated or treated with etoposide as above were used to isolate cytoplasmic fractions. WCL and cytoplasmic fractions were immunoprecipitated with anti-HOPS antibody and subsequently immunoblotted using anti-p53 antibody.
Figure 6A HOPS localization at mitochondria. RKO cells were stained by MitoTracker™ (red), immediately fixed and stained to visualize HOPS (green). Nuclei were DAPI stained (blue). Samples were analysed with fluorescent microscope and representative images were shown. Scale bars, 10µm.B RKO cells were lysed and processed for mitochondria isolation. WCL, cytoplasm and mitochondria were analysed using anti-HOPS antibody. GAPDH, Lamin B1 and Tom20 are purity controls of mitochondrial fraction.C HOPS and p53 translocation to mitochondria. RKO cells were treated with etoposide as indicated and processed for mitochondrial extraction and subsequent immunoblotting for p53, HOPS and the reported extraction purity controls.D HOPS/p53 binding at mitochondria. RKO cells were treated with etoposide and subjected to mitochondrial purification, and subsequent immunoprecipitation using anti-HOPS antibody. Samples were immunoblotted to detect p53, HOPS and the reported controls.E HOPS and p53 mitochondrial translocation in vivo. Hops+/+ and Hops−/− mice were treated with etoposide and thymus, spleen and testis were harvested. Organs were homogenized and mitochondrial fraction were isolated and analysed by immunoblotting versus p53. GAPDH and Tom20 are purity controls. p53 mitochondrial protein levels were semi-quantified using Tom20 as loading control and p53 levels at time 0 were assumed as 1. Data information: assays involving animals were performed three times in three different mice per condition. In E data are presented as mean ±SD. * P < 0.05; *** P < 0.001, by two tailed Student's t-test.F p53-dependent mitochondrial membrane potential (Δψm) induction in MEFs. Hops+/+ and Hops−/− MEFs were treated with etoposide and then incubated with JC-1 vital dye. The images were collected by fluorescent microscopy and representative images are shown (left panel). Scale bars, 10µm. Fluorescence was analysed by TECAN plate reader and plotted in the graph (right panel). Data information: assays involving animals were performed three times in three different mice per condition. Experiments on mitochondria from MEFs were performed five times. In F data are presented as mean ±SD. * P < 0.05; *** P < 0.001, by two tailed Student's t-test.G p53 MOMP induction in HOPS deficiency. Mitochondria from Hops+/+ and Hops−/− MEFs, were purified and incubated with p53 recombinant protein. Cytochrome C release from mitochondria as metabolic marker was assayed by immunoblotting. Samples were tested to detect p53 as control and Tom20 as mitochondria structural marker. Data information: assays involving animals were performed three times in three different mice per condition. Experiments on mitochondria from MEFs were performed five times.