Publications - 2011

  1. Baresova, V., Skopova, V., Sikora, J., Patterson, D., Sovova, J., Zikanova, M., Kmoch, S.:
    Mutations of ATIC and ADSL Affect Purinosome Assembly in Cultured Skin Fibroblasts from Patients with AICA-ribosiduria and ADSL deficiency.
    Hum Mol Genet. 2011 Dec 16. [Epub ahead of print]

  2. Benes, J., Kazdova, L., Drahota, Z., Houstek, J., Medrikova, D., Kopecky, J., Kovarova, N., Vrbacky, M., Sedmera, D., Strnad, H., Kolar, M., Petrak, J., Benada, O., Skaroupkova, P., Cervenka, L., Melenovsky, V:
    Effect of metformin therapy on cardiac function and survival in volume-overload model of heart failure in rats.
    Clinical Sci (Lond). 1121(1): 29-41 (2011)
    Full text: PubMed
    Advanced HF (heart failure) is associated with altered substrate metabolism. Whether modification of substrate use improves the course of HF remains unknown. The antihyperglycaemic drug MET (metformin) affects substrate metabolism, and its use might be associated with improved outcome in diabetic HF. The aim of the present study was to examine whether MET would improve cardiac function and survival also in non-diabetic HF. Volume-overload HF was induced in male Wistar rats by creating ACF (aortocaval fistula). Animals were randomized to placebo/MET (300 mg/kg(-1) of body weight/day(-1), 0.5% in food) groups and underwent assessment of metabolism, cardiovascular and mitochondrial functions (n=6-12/group) in advanced HF stage (week 21). A separate cohort served for survival analysis (n=10-90/group). The ACF group had marked cardiac hypertrophy, increased LVEDP (left ventricular end-diastolic pressure) and lung weight confirming decompensated HF, increased circulating NEFAs (non-esterified 'free' fatty acids), intra-abdominal fat depletion, lower glycogen synthesis in the skeletal muscle (diaphragm), lower myocardial triacylglycerol (triglyceride) content and attenuated myocardial (14)C-glucose and (14)C-palmitate oxidation, but preserved mitochondrial respiratory function, glucose tolerance and insulin sensitivity. MET therapy normalized serum NEFAs, decreased myocardial glucose oxidation, increased myocardial palmitate oxidation, but it had no effect on myocardial gene expression, AMPK (AMP-activated protein kinase) signalling, ATP level, mitochondrial respiration, cardiac morphology, function and long-term survival, despite reaching therapeutic serum levels (2.2±0.7 µg/ml). In conclusion, MET-induced enhancement of myocardial fatty acid oxidation had a neutral effect on cardiac function and survival. Recently reported cardioprotective effects of MET may not be universal to all forms of HF and may require AMPK activation or ATP depletion. No increase in mortality on MET supports its safe use in diabetic HF.
  3. Boell, L., Gregorova, S., Forejt, J., Tautz, D. A:
    Comparative assessment of mandible shape in a consomic strain panel of the house mouse (Mus musculus)implications for epistasis and evolvability of quantitative traits.
    BMC Evol Biol. 1911: 309 (2011)
    Full text: PubMed
    BACKGROUND : Expectations of repeatedly finding associations between given genes and phenotypes have been borne out by studies of parallel evolution, especially for traits involving absence or presence of characters. However, it has rarely been asked whether the genetic basis of quantitative trait variation is conserved at the intra- or even at the interspecific level. This question is especially relevant for shape, where the high dimensionality of variation seems to require a highly complex genetic architecture involving many genes.
    RESULTS : We analyse here the genetic effects of chromosome substitution strains carrying M. m. musculus chromosomes in a largely M. m. domesticus background on mandible shape and compare them to the results of previously published QTL mapping data between M. m. domesticus strains. We find that the distribution of genetic effects and effect sizes across the genome is consistent between the studies, while the specific shape changes associated with the chromosomes are different. We find also that the sum of the effects from the different M. m. musculus chromosomes is very different from the shape of the strain from which they were derived, as well as all known wild type shapes.
    CONCLUSIONS : Our results suggest that the relative chromosome-wide effect sizes are comparable between the long separated subspecies M. m. domesticus and M. m. musculus, hinting at a relative stability of genes involved in this complex trait. However, the absolute effect sizes and the effect directions may be allele-dependent, or are context dependent, i.e. epistatic interactions appear to play an important role in controlling shape.
  4. Flachs, P., Rühl, R., Hensler, M., Janovska, P., Zouhar, P., Kus, V., Macek, Jilkova, Z., Papp, E., Kuda, O., Svobodova, M., Rossmeisl, M., Tsenov, G., Mohamed-Ali, V., Kopecky, J.:
    Synergistic induction of lipid catabolism and anti-inflammatory lipids in white fat of dietary obese mice in response to calorie restriction and n-3 fatty acids.
    Diabetologia 54: 2626-2683 (2011)
    Full text: PubMed
    AIMS/HYPOTHESIS : Calorie restriction is an essential component in the treatment of obesity and associated diseases. Long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) act as natural hypolipidaemics, reduce the risk of cardiovascular disease and could prevent the development of obesity and insulin resistance. We aimed to characterise the effectiveness and underlying mechanisms of the combination treatment with LC n-3 PUFA and 10% calorie restriction in the prevention of obesity and associated disorders in mice.
    METHODS : Male mice (C57BL/6J) were habituated to a corn-oil-based high-fat diet (cHF) for 2 weeks and then randomly assigned to various dietary treatments for 5 weeks or 15 weeks: (1) cHF, ad libitum; (2) cHF with LC n-3 PUFA concentrate replacing 15% (wt/wt) of dietary lipids (cHF + F), ad libitum; (3) cHF with calorie restriction (CR; cHF + CR); and (4) cHF + F + CR. Mice fed a chow diet were also studied.
    RESULTS : We show that white adipose tissue plays an active role in the amelioration of obesity and the improvement of glucose homeostasis by combining LC n-3 PUFA intake and calorie restriction in cHF-fed mice. Specifically in the epididymal fat in the abdomen, but not in other fat depots, synergistic induction of mitochondrial oxidative capacity and lipid catabolism was observed, resulting in increased oxidation of metabolic fuels in the absence of mitochondrial uncoupling, while low-grade inflammation was suppressed, reflecting changes in tissue levels of anti-inflammatory lipid mediators, namely 15-deoxy-Δ(12,15)-prostaglandin J(2) and protectin D1.
    CONCLUSIONS/INTERPRETATION : White adipose tissue metabolism linked to its inflammatory status in obesity could be modulated by combination treatment using calorie restriction and dietary LC n-3 PUFA to improve therapeutic strategies for metabolic syndrome.
  5. Hadravová, R., de Marco, A., Ulbrich, P., Štokrová, J., Doležal, M., Pichová, I., Ruml, T., Briggs, J. A. G., Rumlová, M.:
    In vitro assembly of virus-like particles of a Gammaretrovirus, the Murine Leukemia Virus (XMRV).
    J Virol. 86(4): 1988-98 (2012). Epub 2011 Dec 14.
    Full text: PubMed
    Immature retroviral particles are assembled by self-association of the structural polyprotein precursor Gag. During maturation the Gag polyprotein is proteolytically cleaved, yielding mature structural proteins, matrix (MA), capsid (CA), and nucleocapsid (NC), that reassemble into a mature viral particle. Proteolytic cleavage causes the N terminus of CA to fold back to form a β-hairpin, anchored by an internal salt bridge between the N-terminal proline and the inner aspartate. Using an in vitro assembly system of capsid-nucleocapsid protein (CANC), we studied the formation of virus-like particles (VLP) of a gammaretrovirus, the xenotropic murine leukemia virus (MLV)-related virus (XMRV). We show here that, unlike other retroviruses, XMRV CA and CANC do not assemble tubular particles characteristic of mature assembly. The prevention of β-hairpin formation by the deletion of either the N-terminal proline or 10 initial amino acids enabled the assembly of ΔProCANC or Δ10CANC into immature-like spherical particles. Detailed three-dimensional (3D) structural analysis of these particles revealed that below a disordered N-terminal CA layer, the C terminus of CA assembles a typical immature lattice, which is linked by rod-like densities with the RNP.
  6. Hejzlarová, K., Tesařová, M., Vrbacká-Čížková, A., Vrbacký, M., Hartmannová, H., Kaplanová, V., Nosková, L., Kratochvílová, H., Buzková, J., Havlíčková, V., Zeman, J., Kmoch, S., Houštěk, J.:
    Expression and processing of the TMEM70 protein.
    Biochim. Biophys. Acta 1807(1): 144-9 (2011)
    Full text: PubMed
    TMEM70 protein represents a novel ancillary factor of mammalian ATP synthase. We have investigated import and processing of this factor in human cells using GFP- and FLAG-tagged forms of TMEM70 and specific antibodies. TMEM70 is synthesized as a 29kDa precursor protein that is processed to a 21kDa mature form. Immunocytochemical detection of TMEM70 showed mitochondrial colocalization with MitoTracker Red and ATP synthase. Western blot of subcellular fractions revealed the highest signal of TMEM70 in isolated mitochondria and mitochondrial location was confirmed by mass spectrometry analysis. Based on analysis of submitochondrial fractions, TMEM70 appears to be located in the inner mitochondrial membrane, in accordance with predicated transmembrane regions in the central part of the TMEM70 sequence. Two-dimensional electrophoretic analysis did not show direct interaction of TMEM70 with assembled ATP synthase but indicated the presence of dimeric form of TMEM70. No TMEM70 protein could be found in cells and isolated mitochondria from patients with ATP synthase deficiency due to TMEM70 c.317-2A>G mutation thus confirming that TMEM70 biosynthesis is prevented in these patients.
  7. Homolka, D., Ivanek, R., Forejt, J., Jansa, P.:
    Differential expression of non-coding RNAs and continuous evolution of the X chromosome in testicular transcriptome of two mouse species.
    PLoS One. 2011 Feb 146(2):e17198.
    Full text: PubMed
    BACKGROUND : Tight regulation of testicular gene expression is a prerequisite for male reproductive success, while differentiation of gene activity in spermatogenesis is important during speciation. Thus, comparison of testicular transcriptomes between closely related species can reveal unique regulatory patterns and shed light on evolutionary constraints separating the species.
    METHODOLOGY/PRINCIPAL FINDINGS : Here, we compared testicular transcriptomes of two closely related mouse species, Mus musculus and Mus spretus, which diverged more than one million years ago. We analyzed testicular expression using tiling arrays overlapping Chromosomes 2, X, Y and mitochondrial genome. An excess of differentially regulated non-coding RNAs was found on Chromosome 2 including the intronic antisense RNAs, intergenic RNAs and premature forms of Piwi-interacting RNAs (piRNAs). Moreover, striking difference was found in the expression of X-linked G6pdx gene, the parental gene of the autosomal retrogene G6pd2.
    CONCLUSIONS/SIGNIFICANCE : The prevalence of non-coding RNAs among differentially expressed transcripts indicates their role in species-specific regulation of spermatogenesis. The postmeiotic expression of G6pdx in Mus spretus points towards the continuous evolution of X-chromosome silencing and provides an example of expression change accompanying the out-of-the X-chromosomal retroposition.
  8. Homolka, D., Jansa, P., Forejt, J.:
    Genetically enhanced asynapsis of autosomal chromatin promotes transcriptional dysregulation and meiotic failure.
    Chromosoma 121(1): 91-104 (2012). Epub 2011 Oct 16.
    Full text: PubMed
    During meiosis, pairing of homologous chromosomes and their synapsis are essential prerequisites for normal male gametogenesis. Even limited autosomal asynapsis often leads to spermatogenic impairment, the mechanism of which is not fully understood. The present study was aimed at deliberately increasing the size of partial autosomal asynapsis and analysis of its impact on male meiosis. For this purpose, we studied the effect of t(12) haplotype encompassing four inversions on chromosome 17 on mouse autosomal translocation T(16;17)43H (abbreviated T43H). The T43H/T43H homozygotes were fully fertile in both sexes, while +/T43H heterozygous males, but not females, were sterile with meiotic arrest at late pachynema. Inclusion of the t(12) haplotype in trans to the T43H translocation resulted in enhanced asynapsis of the translocated autosome, ectopic phosphorylation of histone H2AX, persistence of RAD51 foci, and increased gene silencing around the translocation break. Increase was also on colocalization of unsynapsed chromatin with sex body. Remarkably, we found that transcriptional silencing of the unsynapsed autosomal chromatin precedes silencing of sex chromosomes. Based on the present knowledge, we conclude that interference of meiotic silencing of unsynapsed autosomes with meiotic sex chromosome inactivation is the most likely cause of asynapsis-related male sterility.
  9. Honzik, T., Tesarova, M., Magner, M., Mayr, J., Jesina, P., Vesela, K., Wenchich, L., Szentivanyi, K., Hansikova, H., Sperl, W., Zeman, J.:
    Neonatal onset of mitochondrial disorders in 129 patients: clinical and laboratory characteristics and a new approach to diagnosis.
    JIMD - accepted

  10. Kmoch, S., Živná, M., Bleyer, A.J.:
    Familial Juvenile Hyperuricemic Nephropathy Type 2 . In: Pagon RA, Bird TD, Dolan CR, Stephens K, editors. GeneReviews [Internet]. Seattle (WA): University of Washington, Seattle 1993-2011.
    Full text: PubMed
    DISEASE CHARACTERISTICS : Familial juvenile hyperuricemic nephropathy type 2 (FJHN2) is characterized by hypoproliferative anemia with low hemoglobin concentrations found in most affected children by age one year; hyperuricemia and gout found in most (not all) affected individuals; and slowly progressive chronic tubulo-interstitial kidney disease. Some affected children have polyuria (excessive urine production leading to frequent urination) and enuresis. Mildly elevated serum creatinine concentration and reduced estimated glomerular filtration rate in an asymptomatic child often progresses to end-stage renal disease (ESRD) in the fourth to sixth decades of life. Of note, information on only four families with this condition has been published; better understanding of the disease is likely to emerge when more families are described.
    DIAGNOSIS/TESTING : Diagnosis is based on findings of hypoproliferative anemia (low reticulocyte count relative to hemoglobin concentration and low erythropoietin concentration), hyperuricemia (serum uric acid concentration >6 mg/dL), decreased fractional excretion of urinary uric acid, bland urinary sediment, and low plasma renin activity. Kidney size is normal or small with no evidence of cyst formation. Molecular genetic testing of REN (encoding renin), the only gene in which mutations are known to cause FJHN2, is available on a clinical basis.
    MANAGEMENT : Treatment of manifestations: Anemia may be reversed by erythropoietin; gout typically responds well to prednisone or colchicine. Treatment of low plasma renin activity/low plasma concentration of aldosterone may be indicated prior to the development of stage III chronic kidney disease. If hyperkalemia is present, treatment with fludrocortisone or potassium restriction may be indicated. When end-stage kidney disease develops, kidney transplantation can be performed. FJHN2 does not recur in the transplanted kidney, which produces renin in a normal manner. Prevention of primary manifestations: Treatment of hyperuricemia with allopurinol can prevent development of gout. Surveillance: Measurement of hemoglobin concentration and serum concentration of uric acid and creatinine annually starting at the time of diagnosis. Agents/circumstances to avoid: Nonsteroidal anti-inflammatory medications (NSAIDs), especially in persons who are dehydrated. Angiotensin-converting enzyme inhibitors could aggravate the underlying relative renin deficit. Volume depletion and dehydration as well as high meat and seafood intake could exacerbate gout. Testing of relatives at risk: If the REN mutation has been identified in an affected family member, molecular genetic testing of at-risk relatives may be considered, particularly in: children because of their increased risk for anemia; adolescents because of their increased risk of gout, which can be prevented with appropriate treatment; and relatives considering kidney donation.
    GENETIC COUNSELING : FJHN2 is inherited in an autosomal dominant manner. Each child of an affected individual has a 50% chance of inheriting the mutation. No laboratories offering prenatal diagnosis for FJHN2 are listed in the GeneTests Laboratory Directory; however, such testing may be available through laboratories offering custom prenatal testing for families in which the disease-causing mutation has been identified.
  11. Kolanczyk, M., Pech, M., Zemojte, T., Yamamoto, H., Mikula, I., Calvaruso, M.A., van den Brand, M., Richter, R., Fischer, B., Ritz, A., Kossler, N., Thurisch, B., Spoerle, R., Smeitink, J., Kornak, U., Chan, D., Vingron, M., Martasek, P., Lightowlers, R.N., Nijtmans, L., Schuelke, M., Nierhaus, K.H., Mundlos, S.:
    NOA1 is an essential GTPase required for mitochondrial protein synthesis.
    Mol Biol Cell. 122(1): 1-11 (2011)
    Full text: PubMed
    Nitric oxide associated-1 (NOA1) is an evolutionarily conserved guanosine triphosphate (GTP) binding protein that localizes predominantly to mitochondria in mammalian cells. On the basis of bioinformatic analysis, we predicted its possible involvement in ribosomal biogenesis, although this had not been supported by any experimental evidence. Here we determine NOA1 function through generation of knockout mice and in vitro assays. NOA1-deficient mice exhibit midgestation lethality associated with a severe developmental defect of the embryo and trophoblast. Primary embryonic fibroblasts isolated from NOA1 knockout embryos show deficient mitochondrial protein synthesis and a global defect of oxidative phosphorylation (OXPHOS). Additionally, Noa1-/- cells are impaired in staurosporine-induced apoptosis. The analysis of mitochondrial ribosomal subunits from Noa1-/- cells by sucrose gradient centrifugation and Western blotting showed anomalous sedimentation, consistent with a defect in mitochondrial ribosome assembly. Furthermore, in vitro experiments revealed that intrinsic NOA1 GTPase activity was stimulated by bacterial ribosomal constituents. Taken together, our data show that NOA1 is required for mitochondrial protein synthesis, likely due to its yet unidentified role in mitoribosomal biogenesis. Thus, NOA1 is required for such basal mitochondrial functions as adenosine triphosphate (ATP) synthesis and apoptosis.
  12. Kotrba, P., Macková, M., Fišer, J., Macek, T.:
    Biosorption and Metal Removal Through Living Cells, str.197-233. In: Microbial Biosorption of Metals, Kotrba P., Macková M., Macek T. (eds.), ISBN 978-94-007-0442-8, Springer Dordrecht Heidelberg London New York (2011).

  13. Kotrba, P., Rulíšek, L., Ruml, T.:
    Bacterial Surface Display of Metal-Binding Sites, str. 249-283. In: Microbial Biosorption of Metals, Kotrba P., Macková M., Macek T. (eds.), ISBN 978-94-007-0442-8, Springer Dordrecht Heidelberg London New York (2011) 

  14. Křížová, I., Hadravová, R., Štokrová, J., Günterová, J., Doležal, M., Ruml, T., Rumlová, M., Pichová, I.:
    The G-patch domain of Mason-Pfizer monkey virus is a part of reverse transcriptase.
    J Virol. 86(4):1988-98 (2012). Epub 2011 Dec 14.
    Full text: PubMed
    Mason-Pfizer monkey virus (M-PMV), like some other betaretroviruses, encodes a G-patch domain (GPD). This glycine-rich domain, which has been predicted to be an RNA binding module, is invariably localized at the 3' end of the pro gene upstream of the pro-pol ribosomal frameshift sequence of genomic RNAs of betaretroviruses. Following two ribosomal frameshift events and the translation of viral mRNA, the GPD is present in both Gag-Pro and Gag-Pro-Pol polyproteins. During the maturation of the Gag-Pro polyprotein, the GPD transiently remains a C-terminal part of the protease (PR), from which it is then detached by PR itself. The destiny of the Gag-Pro-Pol-encoded GPD remains to be determined. The function of the GPD in the retroviral life cycle is unknown. To elucidate the role of the GPD in the M-PMV replication cycle, alanine-scanning mutational analysis of its most highly conserved residues was performed. A series of individual mutations as well as the deletion of the entire GPD had no effect on M-PMV assembly, polyprotein processing, and RNA incorporation. However, a reduction of the reverse transcriptase (RT) activity, resulting in a drop in M-PMV infectivity, was determined for all GPD mutants. Immunoprecipitation experiments suggested that the GPD is a part of RT and participates in its function. These data indicate that the M-PMV GPD functions as a part of reverse transcriptase rather than protease.
  15. McDermott-Roe, C., Ye, J., Ahmed, R., Sun, X.M., Serafín, A., Ware, J., Bottolo, L., Muckett, P., Cañas, X., Zhang, J., Rowe, G.C., Buchan, R., Lu, H., Braithwaite, A., Mancini, M., Hauton, D., Martí, R., García-Arumí, E., Hubner, N., Jacob, H., Serikawa, T., Zidek, V., Papousek, F., Kolar, F., Cardona, M., Ruiz-Meana, M., García-Dorado, D., Comella, J.X., Felkin, L.E., Barton, P.J., Arany, Z., Pravenec, M., Petretto, E., Sanchis, D., Cook, S.A.:
    Endonuclease G is a novel determinant of cardiac hypertrophy and mitochondrial function.
    Nature 5478(7367): 114-8 (2011)
    Full text: PubMed
    Left ventricular mass (LVM) is a highly heritable trait and an independent risk factor for all-cause mortality. So far, genome-wide association studies have not identified the genetic factors that underlie LVM variation, and the regulatory mechanisms for blood-pressure-independent cardiac hypertrophy remain poorly understood. Unbiased systems genetics approaches in the rat now provide a powerful complementary tool to genome-wide association studies, and we applied integrative genomics to dissect a highly replicated, blood-pressure-independent LVM locus on rat chromosome 3p. Here we identified endonuclease G (Endog), which previously was implicated in apoptosis but not hypertrophy, as the gene at the locus, and we found a loss-of-function mutation in Endog that is associated with increased LVM and impaired cardiac function. Inhibition of Endog in cultured cardiomyocytes resulted in an increase in cell size and hypertrophic biomarkers in the absence of pro-hypertrophic stimulation. Genome-wide network analysis unexpectedly implicated ENDOG in fundamental mitochondrial processes that are unrelated to apoptosis. We showed direct regulation of ENDOG by ERR-α and PGC1α (which are master regulators of mitochondrial and cardiac function), interaction of ENDOG with the mitochondrial genome and ENDOG-mediated regulation of mitochondrial mass. At baseline, the Endog-deleted mouse heart had depleted mitochondria, mitochondrial dysfunction and elevated levels of reactive oxygen species, which were associated with enlarged and steatotic cardiomyocytes. Our study has further established the link between mitochondrial dysfunction, reactive oxygen species and heart disease and has uncovered a role for Endog in maladaptive cardiac hypertrophy.
  16. Melenovsky, V., Benes, J., Skaroupkova, P., Sedmera, D., Strnad, H., Kolar, M., Vlcek, C., Petrak, J., Benes, J. Jr., Papousek, F., Oliyarnyk, O., Kazdova, L., Cervenka, L.:
    Metabolic characterization of volume overload heart failure due to aorto-caval fistula in rats.
    Mol Cell Biochem 354(1-2): 83-96 (2011)
    Full text: PubMed
    Metabolic interactions between adipose tissue and the heart may play an active role in progression of heart failure (HF). The aim of the study was to examine changes in myocardial and adipose tissue metabolism and gene expression in a rat HF model induced by chronic volume overload. HF was induced by volume overload from aorto-caval fistula (ACF) in 3-month-old male Wistar rats and animals were studied in the phase of decompensated HF (22nd week). HF rats showed marked eccentric cardiac hypertrophy, pulmonary congestion, increased LV end-diastolic pressure, and intraabdominal fat depletion. HF rats had preserved glucose tolerance, but increased circulating free fatty acids (FFA) and attenuated insulin response during oral glucose challenge. Isolated organ studies showed preserved responsiveness of adipose tissue lipolysis and lipogenesis to epinephrine and insulin in ACF. The heart of HF animals had markedly reduced triglyceride content (almost to half of controls), attenuated anti-oxidative reserve (GSH/GSSG), upregulated HF markers (ANP, periostin, thrombospondin-4), specific signaling pathways (Wnt, TGF-?), and downregulated enzymes of mitochondrial fatty acid oxidation, citric acid cycle, and respiratory chain. Adipose tissue transcription profiling showed upregulated receptor for gastric inhibitory polypeptide. In conclusion, ACF-induced HF model displays several deregulations of systemic metabolism. Despite elevation of systemic FFAs, myocardial triglycerides are low and insulin levels are attenuated, arguing against a role of lipotoxicity or insulin resistance in this model. Attenuated postprandial insulin response and relative lack of its antilipolytic effects may facilitate intraabdominal fat depletion observed in ACF-HF animals.
  17. Nosková, L., Stránecký, V., Hartmannová, H., Přistoupilová, A., Barešová, V., Ivánek, R., Hůlková, H., Jahnová, H., van der Zee, J., Staropoli, J.F., Sims, K.B., Tyynelä, J., Van Broeckhoven, C., Nijssen, P.C., Mole, S.E., Elleder, M., Kmoch, S.:
    Mutations in DNAJC5, encoding cysteine-string protein alpha, cause autosomal-dominant adult-onset neuronal ceroid lipofuscinosis.
    Am J Hum Genet 1289(2): 241-52 (2011)
    Full text: PubMed
    Autosomal-dominant adult-onset neuronal ceroid lipofuscinosis (ANCL) is characterized by accumulation of autofluorescent storage material in neural tissues and neurodegeneration and has an age of onset in the third decade of life or later. The genetic and molecular basis of the disease has remained unknown for many years. We carried out linkage mapping, gene-expression analysis, exome sequencing, and candidate-gene sequencing in affected individuals from 20 families and/or individuals with simplex cases; we identified in five individuals one of two disease-causing mutations, c.346_348delCTC and c.344T>G, in DNAJC5 encoding cysteine-string protein alpha (CSPα). These mutations-causing a deletion, p.Leu116del, and an amino acid exchange, p.Leu115Arg, respectively-are located within the cysteine-string domain of the protein and affect both palmitoylation-dependent sorting and the amount of CSPα in neuronal cells. The resulting depletion of functional CSPα might cause in parallel the presynaptic dysfunction and the progressive neurodegeneration observed in affected individuals and lysosomal accumulation of misfolded and proteolysis-resistant proteins in the form of characteristic ceroid deposits in neurons. Our work represents an important step in the genetic dissection of a genetically heterogeneous group of ANCLs. It also confirms a neuroprotective role for CSPα in humans and demonstrates the need for detailed investigation of CSPα in the neuronal ceroid lipofuscinoses and other neurodegenerative diseases presenting with neuronal protein aggregation.
  18. Osobová, M., Urban, V., Jedelský, P. L., Borovička, J., Gryndler, M., Ruml, T., Kotrba, P.:
    Three metallothionein isoforms and sequestration of intracellular silver in the hyperaccumulator Amanita strobiliformis.
    New Phytol 190: 916-926 (2011).
    Full text: PubMed
    Metallothioneins (MTs) are cysteine-rich peptides involved in heavy metal tolerance of many eukaryotes. Here, we examined their involvement in intracellular binding of silver (Ag) in the ectomycorrhizal fungus Amanita strobiliformis. The Ag complexes and their peptide ligands were characterized using chromatography and mass spectrometry. The full-length coding sequences obtained from a cDNA library were used for complementation assays in yeast mutant strains. Abundance of respective transcripts in A. strobiliformis was measured by quantitative real-time reverse-transcribed polymerase chain reaction (qRT-PCR). Ag-speciation analyses showed that intracellular Ag was in wild-grown fruit bodies and cultured extraradical mycelia of A. strobiliformis sequestered by metallothioneins. The determined sequence of the peptide facilitated isolation of three cDNA clones, AsMT1a, AsMT1b and AsMT1c. These encode isomorphic MTs consisting of 34 amino acid residues and sharing 82% identity. In mycelia the expression of AsMT1s is induced by Ag. All AsMT1s expressed in yeasts complemented hypersensitivity of mutants to cadmium (Cd) and copper (Cu) and formed Ag complexes. Only the Ag-AsMT1a complex was detected in the A. strobiliformis fruit body in which AsMT1a was the prevailing transcript. The present study identified the existence of metallothionein isoforms in ectomycorrhizal fungi. We demonstrated that intracellular sequestration of Ag in fruit bodies and mycelia of hyperaccumulating A. strobiliformis is dominated by metallothioneins.
  19. Pecinová, A., Drahota, Z., Nůsková, H., Pecina, P., Houštěk, J.:
    Evaluation of basic mitochondrial functions using rat tissue homogenates.
    Mitochondrion 11(5): 722-8 (2011)
    Full text: PubMed
    The primary attempt in diagnostic and experimental studies of numerous pathological states associated with mitochondrial dysfunction is a precise evaluation of changes in function, content and structure of mitochondrial OXPHOS system. The analysis of rat heart, liver, brain and kidney by oxygraphy, enzyme activities, membrane potential, and BN/SDS-PAGE western blotting demonstrated that tissue homogenates can substitute for isolated mitochondria, providing comparable qualitative mitochondrial parameters. The use of homogenate avoids the loss of the majority of mitochondria during their isolation. Only 50-100mg of the tissue is required for the complex OXPHOS analysis, i.e. five times less as compared with isolated mitochondria.
  20. Pravenec, M., Kajiya, T., Zídek, V., Landa, V., Mlejnek, P., Simáková, M., Silhavý, J., Malínská, H., Oliyarnyk, O., Kazdová, L., Fan, J., Wang, J., Kurtz, T.W.:
    Effects of human C-reactive protein on pathogenesis of features of the metabolic syndrome.
    Hypertension 57(4): 731-7 (2011)
    Full text: PubMed
    Major controversy exists as to whether increased C-reactive protein (CRP) contributes to individual components of the metabolic syndrome or is just a secondary response to inflammatory disease processes. We measured blood pressure and metabolic phenotypes in spontaneously hypertensive rats (SHRs) in which we transgenically expressed human CRP in the liver under control of the apolipoprotein E promoter. In transgenic SHRs, serum levels of human CRP approximated the endogenous levels of CRP normally found in the rat. Systolic and diastolic blood pressures measured by telemetry were 10 to 15 mm Hg greater in transgenic SHRs expressing human CRP than in SHR controls (P<0.01). During oral glucose tolerance testing, transgenic SHRs exhibited hyperinsulinemia compared with controls (insulin area under the curve: 36±7 versus 8±2 nmol/L per 2 hours, respectively; P<0.05). Transgenic SHRs also exhibited resistance to insulin stimulated glycogenesis in skeletal muscle (174±18 versus 278±32 nmol of glucose per gram per 2 hours; P<0.05), hypertriglyceridemia (0.84±0.05 versus 0.64±0.03 mmol/L; P<0.05), reduced serum adiponectin (2.4±0.3 versus 4.3±0.6 mmol/L; P<0.05), and microalbuminuria (200±35 versus 26±5 mg of albumin per gram of creatinine, respectively; P<0.001). Transgenic SHRs had evidence of inflammation and oxidative tissue damage with increased serum levels of interleukin 6 (36.4±5.2 versus 18±1.7 pg/mL; P<0.005) and increased hepatic and renal thiobarbituric acid reactive substances (1.2±0.09 versus 0.8±0.07 and 1.5±0.1 versus 1.1±0.05 nmol/L per milligram of protein, respectively; P<0.01), suggesting that oxidative stress may be mediating adverse effects of increased human CRP. These findings are consistent with the hypothesis that increased CRP is more than just a marker of inflammation and can directly promote multiple features of the metabolic syndrome.
  21. Pravenec, M., Zídek, V., Landa, V., Simáková, M., Mlejnek, P., Silhavy, J., Maxová, M., Kazdová, L., Seidman, J.G., Seidman, C.E., Eminaga, S., Gorham, J., Wang, J., Kurtz, T.W.:
    Age-related autocrine diabetogenic effects of transgenic resistin in spontaneously hypertensive rats: gene expression profile analysis.
    Physiol Genomics 1243(7): 372-9 (2011)
    Full text: PubMed
    Increased circulating levels of resistin have been proposed as a possible link between obesity and insulin resistance; however, many of the potential metabolic effects of resistin remain to be investigated, including systemic versus local resistin action. We investigated potential autocrine effects of resistin on lipid and glucose metabolism in 2- and 16-mo-old transgenic spontaneously hypertensive rats (SHR) expressing a nonsecreted form of mouse resistin under control of the aP2 promoter. To search for possible molecular mechanisms, we compared gene expression profiles in adipose tissue in 6-wk-old transgenic SHR versus control rats, before development of insulin resistance, by digital transcriptional profiling using high-throughput sequencing. Both young and old transgenic rats showed moderate expression of the resistin transgene in adipose tissue but had serum resistin levels similar to control SHR and undetectable levels of transgenic resistin in the circulation. Young transgenic rats exhibited mild glucose intolerance. In contrast, older transgenic rats displayed marked glucose intolerance in association with near total resistance of adipose tissue to insulin-stimulated glucose incorporation into lipids (6 ± 2 vs. 77 ± 19 nmol glucose/g(-1)/2 h(-1), P < 0.00001). Ingenuity Pathway Analysis of differentially expressed genes revealed calcium signaling, Nuclear factor-erythroid 2-related factor-2 (NRF2)-mediated oxidative stress response, and actin cytoskeletal signaling canonical pathways as those most significantly affected. Analysis using DAVID software revealed oxidative phosphorylation, glutathione metabolism, pyruvate metabolism, and peroxisome proliferator-activated receptor (PPAR) signaling as top Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. These results suggest that with increasing age autocrine effects of resistin in fat tissue may predispose to diabetes in part by impairing insulin action in adipose tissue.
  22. Prchal, J., Junková, P., Strmisková, M., Lipov, J., Hynek, R., Ruml, T., Lang, J., Hrabal, R.:
    Expression and purification of myristoylated matrix protein of Mason-Pfizer monkey virus for NMR and MS measurements.
    Prot. Expr. Purif. 79: 122-127 (2011)
    Full text: PubMed
    Matrix proteins play multiple roles both in early and late stages of the viral replication cycle. Their N-terminal myristoylation is important for interaction with the host cell membrane during virus budding. We used Escherichia coli, carrying N-myristoyltransferase gene, for the expression of the myristoylated His-tagged matrix protein of Mason-Pfizer monkey virus. An efficient, single-step purification procedure eliminating all contaminating proteins including, importantly, the non-myristoylated matrix protein was designed. The comparison of NMR spectra of matrix protein with its myristoylated form revealed substantial structural changes induced by this fatty acid modification.
  23. Rohlena, J., Dong, L.-F., Kluckova, K., Zobalova, R., Tilly, D., Stursa, J., Pecinova, A., Hozak, P., Mahdavian, E., Salvatore, B.A., Ledvina, M., Houstek, J., Coster, M.J., Neuzil, J.:
    Mitochondrially targeted vitamin E succinate efficiently kills angiogenic endothelial cells and suppresses angiogenesis in vivo.
    Antioxidants & Redox Signaling 12: 2923-2935 (2011)
    Full text: PubMed
    AIMS : A plausible strategy to reduce tumor progress is the inhibition of angiogenesis. Therefore, agents that efficiently suppress angiogenesis can be used for tumor suppression. We tested the antiangiogenic potential of a mitochondrially targeted analog of α-tocopheryl succinate (MitoVES), a compound with high propensity to induce apoptosis.
    RESULTS : MitoVES was found to efficiently kill proliferating endothelial cells (ECs) but not contact-arrested ECs or ECs deficient in mitochondrial DNA, and suppressed angiogenesis in vitro by inducing accumulation of reactive oxygen species and induction of apoptosis in proliferating/angiogenic ECs. Resistance of arrested ECs was ascribed, at least in part, to the lower mitochondrial inner transmembrane potential compared with the proliferating ECs, thus resulting in the lower level of mitochondrial uptake of MitoVES. Shorter-chain homologs of MitoVES were less efficient in angiogenesis inhibition, thus suggesting a molecular mechanism of its activity. Finally, MitoVES was found to suppress HER2-positive breast carcinomas in a transgenic mouse as well as inhibit tumor angiogenesis. The antiangiogenic efficacy of MitoVES was corroborated by its inhibitory activity on wound healing in vivo.
    INNOVATION AND CONCLUSION : We conclude that MitoVES, a mitochondrially targeted analog of α-tocopheryl succinate, is an efficient antiangiogenic agent of potential clinical relevance, exerting considerably higher activity than its untargeted counterpart. MitoVES may be helpful against cancer but may compromise wound healing.
  24. Stiburek, L., Cesnekova, J., Kostkova, O., Fornuskova, D., Vinsova, K., Wenchich, L., Houstek, J., Zeman, J.:
    YME1L controls the accumulation of respiratory chain subunits and is required for apoptotic resistance, cristae morphogenesis and cell proliferation.
    Molecular Biology of the Cell (Mol Biol Cell) - accepted

  25. Strnad, H., Ridl, J., Paces, J., Kolar, M., Vlcek, C., Paces, V.:
    Complete genome sequence of the haloaromatic acid-degrading bacterium Achromobacter xylosoxidans A8.
    J Bacteriol. 193(3): 791-2 (2011)
    Full text: PubMed
    Achromobacter xylosoxidans strain A8 was isolated from soil contaminated with polychlorinated biphenyls. It can use 2-chlorobenzoate and 2,5-dichlorobenzoate as sole sources of carbon and energy. This property makes it a good starting microorganism for further development toward a bioremediation tool. The genome of A. xylosoxidans consists of a 7-Mb chromosome and two large plasmids (98 kb and 248 kb). Besides genes for the utilization of xenobiotic organic substrates, it contains genes associated with pathogenesis, toxin production, and resistance. Here, we report the complete genome sequence.
  26. Szabó, P., Kolář, M., Dvořánková, B., Lacina, L., Štork, J., Vlček, Č., Strnad, H., Tvrdek, M., Smetana, K. Jr.:
    Mouse 3T3 fibroblasts under the influence of fibroblasts isolated from stroma of human basal cell carcinoma acquire properties of multipotent stem cells.
    Biol Cell 103(5): 233-48 (2011)
    Full text: PubMed
    BACKGROUND INFORMATION : Multipotent mesenchymal stem cells can participate in the formation of a microenvironment stimulating the aggressive behaviour of cancer cells. Moreover, cells exhibiting pluripotent ESC (embryonic stem cell) markers (Nanog and Oct4) have been observed in many tumours. Here, we investigate the role of cancer-associated fibroblasts in the formation of stem cell supporting properties of tumour stroma. We test the influence of fibroblasts isolated from basal cell carcinoma on mouse 3T3 fibroblasts, focusing on the expression of stem cell markers and plasticity in vitro by means of microarrays, qRT-PCR (quantitative real-time PCR) and immunohistochemistry.
    RESULTS : We demonstrate the biological activity of the cancer stromal fibroblasts by influencing the 3T3 fibroblasts to express markers such as Oct4, Nanog and Sox2 and to show differentiation potential similar to mesenchymal stem cells. The role of growth factors such as IGF2 (insulin-like growth factor 2), FGF7 (fibroblast growth factor 7), LEP (leptin), NGF (nerve growth factor) and TGFβ (transforming growth factor β), produced by the stromal fibroblasts, is established to participate in their bioactivity. Uninduced 3T3 do not express the stem cell markers and show minimal differentiation potential.
  27. van de Steeg, E., Stránecký, V., Hartmannová, H., Nosková, L., Hrebícek, M., Wagenaar, E., van Esch, A., de Waart, RD., Oude Elferink, R.P.J., Kenworthy, K.E., Sticová, E., al-Edreesi, M., Knisely, A.S., Kmoch, S., Jirsa, M., Schinkel, A.H.:
    Complete OATP1B1 and OATP1B3 deficiency causes human Rotor syndrome by interrupting conjugated bilirubin reuptake into the liver.
    J.Clin.Invest. - 2012 - in press 

  28. Voráčková, I., Suchanová, Š., Ulbrich, P., Diehl, P., Ruml, T.:
    Purification of proteins containing zinc finger domains using Immobilized Metal Ion Affinity Chromatography.
    Prot. Expr. Purif. 79: 88-95 (2011)
    Full text: PubMed
    Heterologous proteins are frequently purified by immobilized metal ion affinity chromatography (IMAC) based on their modification with a hexa-histidine affinity tag (His-tag). The terminal His-tag can, however, alter functional properties of the tagged protein. Numerous strategies for the tag removal have been developed including chemical treatment and insertion of protease target sequences in the protein sequence. Instead of using these approaches, we took an advantage of natural interaction of zinc finger domains with metal ions to purify functionally similar retroviral proteins from two different retroviruses. We found that these proteins exhibited significantly different affinities to the immobilized metal ions, despite that both contain the same type of zinc finger motif (i.e., CCHC). While zinc finger proteins may differ in biochemical properties, the multitude of IMAC platforms should allow relatively simple yet specific method for their isolation in native state.
  29. Xue, F., Kraus, J.M., Labby, K.J., Ji, H., Mataka, J., Xia, G., Li, H., Delker, S.L., Roman, L.J., Martasek, P., Poulos, T.L., Silverman, R.B.:
    Improved synthesis of chiral pyrrolidine inhibitors and their binding properties to neuronal nitric oxide synthase.
    J Med Chem 54(18): 6399-6403 (2011)
    Full text: PubMed
    We report an efficient synthetic route to chiral pyrrolidine inhibitors of neuronal nitric oxide synthase (nNOS) and crystal structures of the inhibitors bound to nNOS and to endothelial NOS. The new route enables versatile structure-activity relationship studies on the pyrrolidine-based scaffold, which can be beneficial for further development of nNOS inhibitors. The X-ray crystal structures of five new fluorine-containing inhibitors bound to nNOS provide insights into the effect of the fluorine atoms on binding.
  30. Xue, F., Fang, J., Delker, S.L., Li, H., Martasek, P., Roman, L.J., Poulos, T.L., Silverman, R.B.:
    Symmetric double-headed aminopyridines, a novel strategy for petent and membrane-permeable inhibitors of neuronal nitric oxide synthase.
    J Med Chem 1454(7): 2039-2048 (2011)
    Full text: PubMed
    We report novel neuronal nitric oxide synthase (nNOS) inhibitors based on a symmetric double-headed aminopyridine scaffold. The inhibitors were designed from crystal structures of leads 1 and 2 (Delker, S. L.; Ji, H.; Li, H.; Jamal, J.; Fang, J.; Xue, F.; Silverman, R. B.; Poulos, T. L. Unexpected binding modes of nitric oxide synthase inhibitors effective in the prevention of cerebral palsy . J. Am. Chem. Soc. 2010, 132, 5437-5442) and synthesized using a highly efficient route. The best inhibitor, 3j, showed low nanomolar inhibitory potency and modest isoform selectivity. It also exhibited enhanced membrane permeability. Inhibitor 3j binds to both the substrate site and the pterin site in nNOS but only to the substrate site in eNOS. These compounds provide a basis for further development of novel, potent, isoform selective, and bioavailable inhibitors for nNOS.