Exploitation of the UDP-glucose hydrolase NUDT22 as novel target in cancer therapy

NUDT22 is a hitherto unstudied family member of the NUDIX protein superfamily. Our group previously identified a specific substrate activity for NUDT22 towards uridine diphosphate (UDP)-glucose resulting in the generation of glucose 1-phosphate (G1P) and the pyrimidine precursor uridine monophosphate (UMP). Fast proliferating cells such as cancer cells can adapt the more energy-efficient nucleoside salvage pathways to maintain sufficient nucleotide pool levels for cell proliferation and to prevent DNA replication stress. Together with the observed NUDT22 expression alterations in cancer, we hypothesised a specific role of NUDT22 in nucleotide synthesis and the potential exploitation of NUDT22 as novel target in cancer therapy. Here, we assessed the effects of NUDT22 knockout in osteosarcoma U2OS, noncancer retinal pigment epithelial hTERT-RPE1, and in breast cancer MCF7 cells on cell proliferation, nucleotide levels, DNA replication stress, DNA damage induction, DNA replication fork speed and cell cycle progression. We determined synergistic changes in cell survival, DNA damage induction and cell cycle progression upon targeting pyrimidine de novo synthesis with nucleoside analogues and other anticancer agents in NUDT22 KO cells and their respective controls. We performed gene expression database analysis of the cancer genome atlas (TCGA) as well as genotype-tissue expression (GTEx) program to assess changes in NUDT22 levels in cancer versus healthy tissue and determined the role of NUDT22 as potential cancer target in vitro and in a MCF7 breast cancer xenograft model. Furthermore, we exploited our group’s previously solved co-crystal structure of NUDT22 in complex with UDP-glucose in virtual screens for the development of NUDT22 inhibitors. The identified and chemically optimised compounds were further evaluated based on enzymatic and cellular activity as well as their target engagement with recombinant protein and in cell lysate. In conclusion, we propose the discovery of a novel pyrimidine salvage pathway through NUDT22 controlling pyrimidine levels for DNA replication stress prevention and cancer growth maintenance. Our in vitro and in vivo findings suggest that NUDT22 is an emerging target for cancer therapy. In addition, we identified potential first-in-class NUDT22 inhibitors that engage their target in both recombinant protein and cell lysate

Tackling Marine Litter - LITTERBASE

Anthropogenic litter contamination of the oceans is a global problem of growing concern and currently receives strongly increasing attention by policy makers, public authorities, media and the general public. Unlike many other pollutants, marine litter on beaches and its deleterious effects on marine mammals, birds and turtles have attracted much attention as they can be directly observed by stakeholders

ATXN2-CAG42 sequesters PABPC1 into insolubility and induces FBXW8 in cerebellum of old ataxic knock-in mice

Spinocerebellar Ataxia Type 2 (SCA2) is caused by expansion of a polyglutamine encoding triplet repeat in the human ATXN2 gene beyond (CAG)31. This is thought to mediate toxic gain-of-function by protein aggregation and to affect RNA processing, resulting in degenerative processes affecting preferentially cerebellar neurons. As a faithful animal model, we generated a knock-in mouse replacing the single CAG of murine Atxn2 with CAG42, a frequent patient genotype. This expansion size was inherited stably. The mice showed phenotypes with reduced weight and later motor incoordination. Although brain Atxn2 mRNA became elevated, soluble ATXN2 protein levels diminished over time, which might explain partial loss-of-function effects. Deficits in soluble ATXN2 protein correlated with the appearance of insoluble ATXN2, a progressive feature in cerebellum possibly reflecting toxic gains-of-function. Since in vitro ATXN2 overexpression was known to reduce levels of its protein interactor PABPC1, we studied expansion effects on PABPC1. In cortex, PABPC1 transcript and soluble and insoluble protein levels were increased. In the more vulnerable cerebellum, the progressive insolubility of PABPC1 was accompanied by decreased soluble protein levels, with PABPC1 mRNA showing no compensatory increase. The sequestration of PABPC1 into insolubility by ATXN2 function gains was validated in human cell culture. To understand consequences on mRNA processing, transcriptome profiles at medium and old age in three different tissues were studied and demonstrated a selective induction of Fbxw8 in the old cerebellum. Fbxw8 is encoded next to the Atxn2 locus and was shown in vitro to decrease the level of expanded insoluble ATXN2 protein. In conclusion, our data support the concept that expanded ATXN2 undergoes progressive insolubility and affects PABPC1 by a toxic gain-of-function mechanism with tissuespecific effects, which may be partially alleviated by the induction of FBXW8

The Molecular Gas Reservoirs of z∼2z\sim 2 Galaxies: A comparison of CO(1-0) and dust-based molecular gas masses

We test the use of long-wavelength dust continuum emission as a molecular gas tracer at high redshift, via a unique sample of 12, z~2 galaxies with observations of both the dust continuum and CO(1-0) line emission (obtained with the Atacama Large Millimeter Array and Karl G. Jansky Very Large Array, respectively). Our work is motivated by recent, high redshift studies that measure molecular gas masses (\ensuremath{\rm{M}_{\rm{mol}}}) via a calibration of the rest-frame $850\mu$m luminosity ($L_\mathrm{850\mu m,rest}$) against the CO(1-0)-derived \ensuremath{\rm{M}_{\rm{mol}}}\ of star-forming galaxies. We hereby test whether this method is valid for the types of high-redshift, star-forming galaxies to which it has been applied. We recover a clear correlation between the rest-frame $850\mu$m luminosity, inferred from the single-band, long-wavelength flux, and the CO(1-0) line luminosity, consistent with the samples used to perform the $850\mu$m calibration. The molecular gas masses, derived from $L_\mathrm{850\mu m,rest}$, agree to within a factor of two with those derived from CO(1-0). We show that this factor of two uncertainty can arise from the values of the dust emissivity index and temperature that need to be assumed in order to extrapolate from the observed frequency to the rest-frame at 850$\mathrm{\mu m}$. The extrapolation to 850$\mathrm{\mu m}$ therefore has a smaller effect on the accuracy of \Mmol\ derived via single-band dust-continuum observations than the assumed CO(1-0)-to-\ensuremath{\rm{M}_{\rm{mol}}}\ conversion factor. We therefore conclude that single-band observations of long-wavelength dust emission can be used to reliably constrain the molecular gas masses of massive, star-forming galaxies at $z\gtrsim2$

Molecular Genetic Identification of Apple Cultivars Based on Microsatellite DNA Analysis. I. The Database of 600 Validated Profiles

AbstractApple (Malus × domestica Borkh.) is the most widely grown permanent fruit crop of temperate climates. Although commercial apple growing is based on a small number of globally spread cultivars, its diversity is much larger and there are estimates about the existence of more than 10,000 documented varieties. The varietal diversity can be described and determined based on phenotypic characters of the external and internal traits of fruit, which, however, can be modulated by environmental factors. Consequently, molecular methods have become an important alternative means for the characterisation of apple cultivar diversity. In order to use multilocus microsatellite data for determination of unidentified or misidentified apple varieties, a database with molecular genetic fingerprints of well-determined reference cultivars needs to be available. The objective of the present work was to establish such a database that could be applied for the molecular genetic determination of a large number of historic and modern, diploid and triploid apple cultivars. Based on the analysis of more than 1600 accessions of apple trees sampled in 37 public and private cultivar collections in different European countries at 14 variable microsatellite loci, a database with 600 molecular genetic profiles was finally obtained. The key criterion for considering a molecular genetic profile as confirmed and for including it into the reference database was that at least two accessions of the same cultivar of different provenances generated an identical result, which was achieved for 98% of the apple cultivars present in the database. For the remaining genotypes, the cultivar assignment was supported by a parentage analysis or by comparison to molecular genetic profiles available in published works. The database is composed of 574 scion cultivars, 24 rootstock genotypes and two species of crab apples. Of the 574 scion cultivars, 61% were derived from historic or old cultivars, many of which were grown in Central Europe in the past. The remaining scion cultivars are currently grown or available in testing programmes and may gain importance in the future. In order to validate the genotyping data, parentage analysis was performed involving cultivars and rootstocks that arose after 1900, for which information about at least one parent cultivar was available from pomological and scientific literature and the molecular genetic profiles of the assumed parent(s) were also present in our database. This analysis revealed the presence of null alleles at locus COL, however, when excluding this locus, a mean genotyping error rate of only 0.28% per locus was revealed, which points to a high reliability of the dataset. The datasets with 14 and 13 loci (excluding locus COL) showed a high degree of discrimination power, with a combined non-exclusion probability of identity of 2.6 × 10−20 and 3.4 × 10−19. Five of the microsatellite loci analysed in the present study overlapped with another published dataset and after the application of conversion values, it was possible to align the allele lengths and compare the molecular genetic profiles of 20 randomly derived cultivars, which were analysed in both studies. This comparison evidenced an exact correspondence of the microsatellite profiles contained in the two datasets, further pointing to the accuracy of our database. Apart from its application to characterise genetic resources or to manage germplasm collections, the here presented database could serve as an important tool for quality control or as a useful instrument in breeding programmes

DDR2 controls breast tumor stiffness and metastasis by regulating integrin mediated mechanotransduction in CAFs

Biomechanical changes in the tumor microenvironment influence tumor progression and metastases. Collagen content and fiber organization within the tumor stroma are major contributors to biomechanical changes (e., tumor stiffness) and correlated with tumor aggressiveness and outcome. What signals and in what cells control collagen organization within the tumors, and how, is not fully understood. We show in mouse breast tumors that the action of the collagen receptor DDR2 in CAFs controls tumor stiffness by reorganizing collagen fibers specifically at the tumor-stromal boundary. These changes were associated with lung metastases. The action of DDR2 in mouse and human CAFs, and tumors in vivo, was found to influence mechanotransduction by controlling full collagen-binding integrin activation via Rap1-mediated Talin1 and Kindlin2 recruitment. The action of DDR2 in tumor CAFs is thus critical for remodeling collagen fibers at the tumor-stromal boundary to generate a physically permissive tumor microenvironment for tumor cell invasion and metastases

The Effects of Democratic and Nondemocratic Institutions on CO2 Emissions

Democratic institutions that coordinate diffuse interests might be beneficial for climate protection. Because the implementation of democratic institutions varies among democracies as well as among autocracies, this study examines whether institutional aspects of different models of democracy affect CO2 emissions in democracies and autocracies. Similar studies have assumed uniform effects of democratic aspects in regimes of both types. The extent of the dependence of autocratic leaders on the support of the ruling party, the military, and/or a hereditary council might make them less responsive to incentives generated by democratic institutions to reduce CO2 emissions. This article, therefore, examines data on CO2 emissions from 1990 to 2020 in 66 democracies and 69 autocracies separately and analyses whether nondemocratic institutions limit the effects of democratic institutions. As democratic institutions might affect climate outcomes only in the long term, we examine cross-national variation in the long-term development of CO2 emissions and short-term changes in CO2 emissions within countries. In democracies, civil society participation and social equality contribute to a decrease in the long-term development of CO2 emissions. In autocracies, local and regional democracy contributes to lower CO2 emissions in the long term, and social equality decreases annual changes in CO2 emissions. Military influence limits these effects. In contrast, the dependence of the executive on a ruling party strengthens the negative effect of social equality on annual changes in CO2 emissions

Selected human rights indicators in the context of current EU regulation: Towards more social sustainability in the financial and economic system. Part II: Substantial Contribution

In March 2018, the European Commission published its Action Plan on Financing Sustainable Growth. Part of the plan calls for the EU to develop classification systems for environmentally and socially sustainable activities to help direct private sector financing to such activities. This is the second briefing paper of a research project aimed at discussing and developing concepts and indicators for the standardised measurement of socially sustainable activities in alignment with international human rights

Selected human rights indicators in the context of current EU regulation: Towards more social sustainability in the financial and economic system. Part I: Minimum standards

This briefing paper, funded by the German Federal Ministry of Labour and Social Affairs (BMAS), develops 15 central indicators to represent a “minimum standard”. Indicators cover key human rights and key due diligence processes and were drawn from indicator sets widely used in practice; where useful we also suggest refinements of the existing indicators

Preclinical Deposition of Pathological Prion Protein in Muscle of Experimentally Infected Primates

Prion diseases are transmissible fatal neurodegenerative disorders affecting humans and animals. A central step in disease progression is the accumulation of a misfolded form (PrPSc) of the host encoded prion protein (PrPC) in neuronal and non-neuronal tissues. The involvement of peripheral tissues in preclinical states increases the risk of accidental transmission. On the other hand, detection of PrPSc in non-neuronal easy-accessible compartments such as muscle may offer a novel diagnostic tool. Primate models have proven invaluable to investigate prion diseases. We have studied the deposition of PrPSc in muscle and central nervous system of rhesus monkeys challenged with sporadic Creutzfeldt-Jakob disease (sCJD), variant CJD (vCJD) and bovine spongiform encephalopathy (BSE) in preclinical and clinical stage using biochemical and morphological methods. Here, we show the preclinical presence of PrPSc in muscle and central nervous system of rhesus monkeys experimentally infected with vCJD