Deoxynivalenol induces structural alterations in epidermoid carcinoma cells A431 and impairs the response to biomechanical stimulation

Morphology together with the capability to respond to surrounding stimuli are key elements governing the spatial interaction of living cells with the environment. In this respect, biomechanical stimulation can trigger significant physiological cascades that can potentially modulate toxicity. Deoxynivalenol (DON, vomitoxin) is one of the most prevalent mycotoxins produced by Fusarium spp. and it was used to explore the delicate interaction between biomechanical stimulation and cytotoxicity in A431 cells. In fact, in addition of being a food contaminant, DON is a relevant toxin for several organ systems. The combination between biomechanical stimulation and the mycotoxin revealed how DON can impair crucial functions affecting cellular morphology, tubulin and lysosomes at concentrations even below those known to be cytotoxic in routine toxicity studies. Sub-toxic concentrations of DON (0.1\u20131 \u3bcM) impaired the capability of A431 cells to respond to a biomechanical stimulation that normally sustains trophic effects in these cells. Moreover, the effects of DON (0.1\u201310 \u3bcM) were partially modulated by the application of uniaxial stretching (0.5 Hz, 24 h, 15% deformation). Ultimately, proteomic analysis revealed the potential of DON to alter several proteins necessary for cell adhesion and cytoskeletal modulation suggesting a molecular link between biomechanics and the cytotoxic potential of the mycotoxin

Seeding the meiotic DNA break machinery and initiating recombination on chromosome axes

Programmed DNA double-strand break (DSB) formation is a crucial feature of meiosis in most organisms. DSBs initiate recombination-mediated linking of homologous chromosomes, which enables correct chromosome segregation in meiosis. DSBs are generated on chromosome axes by heterooligomeric focal clusters of DSB-factors. Whereas DNA-driven protein condensation is thought to assemble the DSB-machinery, its targeting to chromosome axes is poorly understood. We uncover in mice that efficient biogenesis of DSB-machinery clusters requires seeding by axial IHO1 platforms. Both IHO1 phosphorylation and formation of axial IHO1 platforms are diminished by chemical inhibition of DBF4-dependent kinase (DDK), suggesting that DDK contributes to the control of the axial DSB-machinery. Furthermore, we show that axial IHO1 platforms are based on an interaction between IHO1 and the chromosomal axis component HORMAD1. IHO1-HORMAD1-mediated seeding of the DSB-machinery on axes ensures sufficiency of DSBs for efficient pairing of homologous chromosomes. Without IHO1-HORMAD1 interaction, residual DSBs depend on ANKRD31, which enhances both the seeding and the growth of DSB-machinery clusters. Thus, recombination initiation is ensured by complementary pathways that differentially support seeding and growth of DSB-machinery clusters, thereby synergistically enabling DSB-machinery condensation on chromosomal axes.Meiotic cells deliberately break their DNA to allow chromosomes to swap genetic material. Here, authors reveal genetically separable pathways controlling the seeding and growth of chromosome-bound protein condensates responsible for DNA breaks

Autosomal and mitochondrial adaptation following admixture: a case study on the honeybees of Reunion Island.

The honeybee population of the tropical Reunion Island is a genetic admixture of the Apis mellifera unicolor subspecies, originally described in Madagascar, and of European subspecies, mainly A.m. carnica and A. m. ligustica, regularly imported to the island since the late 19th century. We took advantage of this population to study genetic admixing of the tropical-adapted indigenous and temperate-adapted European genetic backgrounds. Whole genome sequencing of 30 workers and 6 males from Reunion, compared to samples from Europe, Madagascar, Mauritius, Rodrigues and the Seychelles, revealed the Reunion honeybee population to be composed on average of 53.2 ± 5.9% A. m. unicolor nuclear genomic background, the rest being mainly composed of A. m. carnica and to a lesser extent A. m. ligustica. In striking contrast to this, only one out of the 36 honeybees from Reunion had a mitochondrial genome of European origin, suggesting selection has favoured the A. m. unicolor mitotype, which is possibly better adapted to the island's bioclimate. Local ancestry was determined along the chromosomes for all Reunion samples, and a test for preferential selection for the A. m. unicolor or European background revealed 15 regions significantly associated with the A. m. unicolor lineage and 9 regions with the European lineage. Our results provide insights into the long-term consequences of introducing exotic specimen on the nuclear and mitochondrial genomes of locally-adapted populations. (Résumé d'auteur

Disease associated protein alteration of platelets of melanoma patients is associated with characteristic eicosanoid patterns in the releasate

Um ein besseres Verständnis biologischer Systeme vor allem in Zusammenhang mit schweren Krankheiten wie Krebs zu erreichen, werden heute Genomic, Transcriptomic, Proteomic Lipidomic und Metabolomic Methoden in der Forschung verwendet. Aber nicht nur die Prozesse die zur Entwicklung von Tumoren führen sind dabei interessant, sondern auch wie eine Krebserkrankung das ganze System beeinflussen kann. Blutplättchen können einerseits den Verlauf einer solchen Erkrankung beeinflussen andererseits gibt es aber auch Hinweise darauf, dass sie selbst im Laufe einer schweren Krankheit verändert werden. Diese Arbeit stellt eine analytische Methode vor, welche es ermöglicht die bei Aktivierung freigesetzten Eicosanoide von Blutplättchen zu analysieren. Dafür wurden Blutplättchen von vier Patienten mit Melanom und einem gesunden Spender entnommen und gereinigt. Die Plättchen wurden mit Ionomycin aktiviert um eine Ausschüttung der Eicosanoide zu erreichen. Die Proteine des Überstands wurden ausgefällt und die Eicosanoide mit einer Festphasen-Extraktion gereinigt. Die Lipide wurden mittels eines HPLC-MS/MS Systems analysiert, und die Daten manuell ausgewertet. Mit dieser Methode konnten 28 verschieden Eicosanoide unter anderem HETEs, PGs, Hepoxilin und Thromboxan identifiziert werden. Acht weitere Eicosanoide konnten mit geringerer Sicherheit identifiziert werden, werden aber dennoch in den Proben vermutet. Die Lipide wurden quantifiziert und die Werte der Kontrollproben mit denen der 15 Minuten und drei Stunden aktivierten verglichen. Dies zeigt einerseits die Unterschiede zwischen den einzelnen Subklassen der Eicosanoide. Die HETEs zum Beispiel zeigen eine sehr starke Erhöhung nach drei Stunden wohingegen die PGs nur eine sehr geringe Erhöhung zeigen. Andererseits gibt es einen signifikanten Unterschied zwischen den Patienten und dem gesunden Spender. Insgesamt zeigen die Plättchen der erkrankten Spender eine sehr viel geringere Ausschüttung von Lipiden als die gesunden Blutplättchen, was ein Anzeichen dafür sein kann, dass sie die Plättchen in einem erschöpften Zustand befinden und ihre Aktivität unterschiedlich ist, je nachdem in welchem Stadium sich die Krankheit befindet.In order to achieve a better understanding of biological systems per se but especially in correlation with different severe diseases like cancer genomic, transcriptomic, proteomic, lipidomic and metabolomic methods are today widely used for research. But not only the processes that influence the development and progression of tumors are interests of research but also how the cancer affects the whole system. The blood platelets are described to influence cancer and on the other hand are changed by cancer themselves [5]. This work presents an analytical method that allows the analysis of the releasate pattern of eicosanoids of blood platelets. Therefore blood platelets of four patients diagnosed with melanoma and one healthy donor were derived and purified. The platelets have been activated with ionomycin in order to achieve the production and release of eicosanoids. The proteins of the supernatant were precipitated and the eicosanoids purified with a solid-phase extraction. The lipids were analysed using a HPLC-MS/MS system and the data was evaluated manually. With this method 28 eicosanoids including HETEs, PGs, thromboxane, hepoxilin and others could be identified and quantified. Additional 8 eicosanoids were identified with lower certainty but are believed be in the sample as well. The lipids were quantified and the values of the control samples were compared to the ones of the platelets activated for 15 minutes or three hours. This showed, on the one hand, a difference between the distinct subclasses of eicosanoids. The HETEs for example showed a very high fold change whereas the PGs showed very little change. On the other hand, there was a visible difference between the patients and the healthy donor. Overall the diseased platelets showed a much lower fold change than the healthy platelets, which could be an indicator for an exhaustion of the platelets and a change in the activity in different stages of the disease

Identification of runs of homozygosity in Western honey bees (<i>Apis mellifera</i>) using whole‐genome sequencing data

Runs of homozygosity (ROH) are continuous homozygous segments that arise through the transmission of haplotypes that are identical by descent. The length and distribution of ROH segments provide insights into the genetic diversity of populations and can be associated with selection signatures. Here, we analyzed reconstructed whole‐genome queen genotypes, from a pool‐seq data experiment including 265 Western honeybee colonies from Apis mellifera mellifera and Apis mellifera carnica. Integrating individual ROH patterns and admixture levels in a dynamic population network visualization allowed us to ascertain major differences between the two subspecies. Within A. m. mellifera, we identified well‐defined substructures according to the genetic origin of the queens. Despite the current applied conservation efforts, we pinpointed 79 admixed queens. Genomic inbreeding (F$_{ROH}$) strongly varied within and between the identified subpopulations. Conserved A. m. mellifera from Switzerland had the highest mean F$_{ROH}$ (3.39%), while queens originating from a conservation area in France, which were also highly admixed, showed significantly lower F$_{ROH}$ (0.45%). The majority of A. m. carnica queens were also highly admixed, except 12 purebred queens with a mean F$_{ROH}$ of 2.33%. Within the breed‐specific ROH islands, we identified 14 coding genes for A. m. mellifera and five for A. m. carnica, respectively. Local adaption of A. m. mellifera could be suggested by the identification of genes involved in the response to ultraviolet light (Crh‐BP, Uvop) and body size (Hex70a, Hex70b), while the A. m. carnica specific genes Cpr3 and Cpr4 are most likely associated with the lighter striping pattern, a morphological phenotype expected in this subspecies. We demonstrated that queen genotypes derived from pooled workers are useful tool to unravel the population dynamics in A. mellifera and provide fundamental information to conserve native honey bees

Exploring two honey bee traits for improving resistance against Varroadestructor: development and genetic evaluation

For the development of novel selection traits in honey bees, applicability under field conditions is crucial. We thus evaluated two novel traits intended to provide resistance against the ectoparasitic mite Varroa destructor and to allow for their straightforward implementation in honey bee selection. These traits are new field estimates of already-described colony traits: brood recapping rate (‘Recapping’) and solidness (‘Solidness’). ‘Recapping’ refers to a specific worker characteristic wherein they reseal a capped and partly opened cell containing a pupa, whilst ‘Solidness’ assesses the percentage of capped brood in a predefined area. According to the literature and beekeepers’ experiences, a higher recapping rate and higher solidness could be related to resistance to V. destructor. During a four-year field trial in Switzerland, the two resistance traits were assessed in a total of 121 colonies of Apis mellifera mellifera. We estimated the repeatability and the heritability of the two traits and determined their phenotypic correlations with commonly applied selection traits, including other putative resistance traits. Both traits showed low repeatability between different measurements within each year. ‘Recapping’ had a low heritability (h2 = 0.04 to 0.05, depending on the selected model) and a negative phenotypic correlation to non-removal of pin-killed brood (r = −0.23). The heritability of ‘Solidness’ was moderate (h2 = 0.24 to 0.25) and did not significantly correlate with resistance traits. The two traits did not show an association with V. destructor infestation levels. Further research is needed to confirm the results, as only a small number of colonies was evaluate

A Proteomic Platform Enables to Test for AML Normalization In Vitro

Acute promyelocytic leukaemia (APL) can be cured by the co-administration of arsenic trioxide (ATO) and all-trans retinoic acid (ATRA). These small molecules relieve the differentiation blockade of the transformed promyelocytes and trigger their maturation into functional neutrophils, which are physiologically primed for apoptosis. This normalization therapy represents a compelling alternative to cytotoxic anticancer chemotherapy, but lacks an in vitro model system for testing the efficiency of novel combination treatments consisting of inducers of differentiation and metallopharmaceuticals. Here, using proteome profiling we present an experimental framework that enables characterising the differentiation- and metal-specific effects of the combination treatment in a panel of acute myeloid leukaemia (AML) cell lines (HL-60 and U937), including APL (NB4). Differentiation had a substantial impact on the proteome on the order of 10% of the identified proteins and featured classical markers and transcription factors of myeloid differentiation. Additionally, ATO provoked specific cytoprotective effects in the AML cell lines HL-60 and U937. In HL-60, these effects included an integrated stress response (ISR) in conjunction with redox defence, while proteasomal responses and a metabolic rewiring were observed in U937 cells. In contrast, the APL cell line NB4 did not display such adaptions indicating a lack of plasticity to cope with the metal-induced stress, which may explain the clinical success of this combination treatment. Based on the induction of these cytoprotective effects, we proposed a novel metal-based compound to be used for the combination treatment instead of ATO. The organoruthenium drug candidate plecstatin-1 was previously shown to induce reactive oxygen species and an ISR. Indeed, the plecstatin-1 combination was found to affect similar pathways compared to the ATO combination in HL-60 cells and did not lead to cytoprotective response signatures in NB4. Moreover, the monocytic cell line U937 showed a low plasticity to cope with the plecstatin-1 combination, which suggests that this combination might achieve therapeutic benefit beyond APL. We propose that the cytoprotective plasticity of cancer cells might serve as a general proxy to discover novel combination treatments in vitro

Estimates of genetic parameters for production, behaviour, and health traits in two Swiss honey bee populations

Successful honey bee breeding programmes require traits that can be genetically improved by selection. Heritabilities for production, behaviour, and health traits, as well as their phenotypic correlations, were estimated in two distinct Swiss Apis mellifera mellifera and Apis mellifera carnica populations based on 9 years of performance records and more than two decades of pedigree information. Breeding values were estimated by a best linear unbiased prediction (BLUP) approach, taking either queen or worker effects into account. In A. m. mellifera, the highest heritabilities were obtained for defensive behaviour, calmness during inspection, and hygienic behaviour, while in A. m. carnica, honey yield and hygienic behaviour were the most heritable traits. In contrast, estimates for infestation rates by Varroa destructor suggest that the phenotypic variation cannot be attributed to an additive genetic origin in either population. The highest phenotypic correlations were determined between defensive behaviour and calmness during inspection. The implications of these findings for testing methods and the management of the breeding programme are discussed.</p

An Anticancer Rhenium Tricarbonyl Targets Fe-S Cluster Biogenesis in Ovarian Cancer Cells.

Target identification remains a critical challenge in inorganic drug discovery to deconvolute potential polypharmacology. Herein, we describe an improved approach to prioritize candidate protein targets based on a combination of dose-dependent chemoproteomics and treatment effects in living cancer cells for the rhenium tricarbonyl compound TRIP. Chemoproteomics revealed 89 distinct dose-dependent targets with concentrations of competitive saturation between 0.1 and 32 μM despite the broad proteotoxic effects of TRIP. Target-response networks revealed two highly probable targets of which the Fe-S cluster biogenesis factor NUBP2 was competitively saturated by free TRIP at nanomolar concentrations. Importantly, TRIP treatment led to a down-regulation of Fe-S cluster containing proteins and upregulated ferritin. Fe-S cluster depletion was further verified by assessing mitochondrial bioenergetics. Consequently, TRIP emerges as a first-in-class modulator of the scaffold protein NUBP2, which disturbs Fe-S cluster biogenesis at sub-cytotoxic concentrations in ovarian cancer cells

Epithelial Cell Line Derived from Endometriotic Lesion Mimics Macrophage Nervous Mechanism of Pain Generation on Proteome and Metabolome Levels

Endometriosis is a benign disease affecting one in ten women of reproductive age worldwide. Although the pain level is not correlated to the extent of the disease, it is still one of the cardinal symptoms strongly affecting the patients’ quality of life. Yet, a molecular mechanism of this pathology, including the formation of pain, remains to be defined. Recent studies have indicated a close interaction between newly generated nerve cells and macrophages, leading to neurogenic inflammation in the pelvic area. In this context, the responsiveness of an endometriotic cell culture model was characterized upon inflammatory stimulation by employing a multi-omics approach, including proteomics, metabolomics and eicosanoid analysis. Differential proteomic profiling of the 12-Z endometriotic cell line treated with TNFα and IL1β unexpectedly showed that the inflammatory stimulation was able to induce a protein signature associated with neuroangiogenesis, specifically including neuropilins (NRP1/2). Untargeted metabolomic profiling in the same setup further revealed that the endometriotic cells were capable of the autonomous production of 7,8-dihydrobiopterin (BH2), 7,8-dihydroneopterin, normetanephrine and epinephrine. These metabolites are related to the development of neuropathic pain and the former three were found up-regulated upon inflammatory stimulation. Additionally, 12-Z cells were found to secrete the mono-oxygenated oxylipin 16-HETE, a known inhibitor of neutrophil aggregation and adhesion. Thus, inflammatory stimulation of endometriotic 12-Z cells led to specific protein and metabolite expression changes suggesting a direct involvement of these epithelial-like cells in endometriosis pain development