Mutual maintenance of di- and triploid Pelophylax esculentus hybrids in R-E systems: results fro

Background: Interspecies animal hybrids can employ clonal or hemiclonal reproduction modes where one or all parental genomes are transmitted to the progeny without recombination. Nevertheless, some interspecies hybrids retain strong connection with the parental species needed for successful reproduction. Appearance of polyploid hybrid animals may play an important role in the substitution of parental species and in the speciation process. Results: To establish the mechanisms that enable parental species, diploid and polyploid hybrids coexist we have performed artificial crossing experiments of water frogs of Pelophylax esculentus complex. We identified tadpole karyotypes and oocyte genome composition in all females involved in the crossings. The majority of diploid and triploid hybrid frogs produced oocytes with 13 bivalents leading to haploid gametes with the same genome as parental species hybrids usually coexist with. After fertilization of such gametes only diploid animals appeared. Oocytes with 26 bivalents produced by some diploid hybrid frogs lead to diploid gametes, which give rise to triploid hybrids after fertilization. In gonads of all diploid and triploid hybrid tadpoles we found DAPI-positive micronuclei (nucleus-like bodies) involved in selective genome elimination. Hybrid male and female individuals produced tadpoles with variable karyotype and ploidy even in one crossing owing to gametes with various genome composition. Conclusions: We propose a model of diploid and triploid hybrid frog reproduction in R-E population systems. Triploid Pelophylax esculentus hybrids can transmit genome of parental species they coexist with by producing haploid gametes with the same genome composition. Triploid hybrids cannot produce triploid individuals after crossings with each other and depend on diploid hybrid females producing diploid eggs. In contrast to other population systems, the majority of diploid and triploid hybrid females unexpectedly produced gametes with the same genome as parental species hybrids coexist with

The Comprehensive Soldier and Family Fitness Program Evaluation. Report #4: Evaluation of Resilience Training and Mental and Behavioral Health Outcomes

The purpose of this evaluation is to examine the effectiveness of Master Resilience Training, which is a pillar of the Comprehensive Soldier and Family Fitness (CSF2) program. The report evaluates the relationship between resilience training and diagnoses for mental health or substance abuse problems and whether this relationship was mediated by Soldiers’ self-reported resilience/ psychological health (R/PH). In other words, we tested whether Soldiers with MRT trainers in their units experienced increases in self-reported R/PH, and whether increases in self-reported R/PH were associated with reduced odds of Soldiers receiving diagnoses for mental health or substance abuse problems. The results revealed that exposure to resilience training increased various aspects of Soldier R/PH, which, in turn, appeared to be associated with a reduced likelihood of receiving a diagnosis for a mental health problem (i.e., anxiety, depression, or posttraumatic stress disorder [PTSD]). Thus, this finding suggested that the reduced odds of receiving a diagnosis for a mental health problem was partly due to increases in indicators of R/PH that were likely associated with exposure to resilience training. Moreover, the findings provided evidence that Soldiers exposed to the training were diagnosed with substance abuse problems at a significantly lower rate than Soldiers who were not exposed to the training. Importantly, the results of this evaluation bolster findings from previous evaluations by employing more sophisticated and stringent statistical techniques to demonstrate that resilience training can improve the R/PH of Soldiers. Additionally, the analyses included in this evaluation accounted for the potential effects of Soldier deployment; these considerations were not made in previous evaluations of the program. Therefore, the current evaluation provides further evidence that resilience training may improve the self-reported R/PH of Soldiers, even when controlling for a wider range of factors that might be expected to impact the R/PH of Soldiers. The findings of this evaluation have a number of implications. First, this evaluation provides some evidence that resilience training may be related to improvements on objective measures of mental and behavioral outcomes (i.e., diagnoses for mental health and substance abuse problems). Second, when considered at the organizational level, the effects of resilience training may reach beyond improving the health of individual Soldiers by improving the aggregate health and effectiveness of the Army as an organization. Given that diagnoses for mental health disorders are a leading cause for hospitalization in the Armed Forces (Armed Forces Health Surveillance Center, 2012b), the findings provide evidence that interventions such as those offered by CSF2 may help relieve the stress that is currently being placed on medical services in the Army. In sum, it appears that the improvement of R/PH through resilience training efforts can protect against problems that undermine the effectiveness and efficiency of the Army. As with any large-scale evaluation of this type, there are a number of limitations to be acknowledged. First, the timing of deployment cycles of Soldiers in the eight Brigade Combat Teams (BCTs) that were examined introduced potential confounds with regard to the timing of resilience training and data collection efforts for use in this report. Specifically, it appeared that the timing of deployments was such that Soldiers with MRTs in their units were more likely to have been deployed to combat than were those who had no MRT trainers in their units. This means that Soldiers who received resilience training were also more likely to have experienced combat which likely increased the probability of subsequently experiencing the adverse outcomes examined in this study. While this fact posed a potential confound, statistical controls were put in place that allowed for a meaningful test of the resilience training program’s effect on R/PH and diagnoses for mental health and substance abuse problems. Other limitations of this evaluation effort have been described elsewhere (Lester, Harms, Herian, Krasikova & Beal, 2011c) and are expanded upon later in this report. In light of these limitations, it is important that readers recognize two points when reviewing this report. First, this report builds on previous evaluations of the CSF2 program. Specifically, the analyses used here were more stringent given the nature of the data. It is important to note that, given the more rigorous testing methods, the results of this and previous evaluations are fairly consistent. Second, it is critical to recognize that the findings presented in this report represent the latest effort in an ongoing evaluation of the resilience training program. Future analyses may also be conducted that empirically explore the relationship between resilience training and other objective outcomes. If such analyses are undertaken, it is possible that the results may differ from those presented here and in previous evaluations due to the amount of time that has passed since implementation of the training program. In the end, however, the effectiveness of CSF2 cannot be judged solely on the results of any single evaluation, but instead must be considered in light of the entire body of work done to date

Avian W and mammalian Y chromosomes convergently retained dosage-sensitive regulators

After birds diverged from mammals, different ancestral autosomes evolved into sex chromosomes in each lineage. In birds, females are ZW and males are ZZ, but in mammals females are XX and males are XY. We sequenced the chicken W chromosome, compared its gene content with our reconstruction of the ancestral autosomes, and followed the evolutionary trajectory of ancestral W-linked genes across birds. Avian W chromosomes evolved in parallel with mammalian Y chromosomes, preserving ancestral genes through selection to maintain the dosage of broadly expressed regulators of key cellular processes. We propose that, like the human Y chromosome, the chicken W chromosome is essential for embryonic viability of the heterogametic sex. Unlike other sequenced sex chromosomes, the chicken W chromosome did not acquire and amplify genes specifically expressed in reproductive tissues. We speculate that the pressures that drive the acquisition of reproduction-related genes on sex chromosomes may be specific to the male germ line

A multi-omics approach to elucidate okadaic acid-induced changes in human HepaRG hepatocarcinoma cells

Okadaic acid (OA), a prevalent marine biotoxin found in shellfish, is known for causing acute gastrointestinal symptoms. Despite its potential to reach the bloodstream and the liver, the hepatic effects of OA are not well understood, highlighting a significant research gap. This study aims to comprehensively elucidate the impact of OA on the liver by examining the transcriptome, proteome, and phosphoproteome alterations in human HepaRG liver cells exposed to non-cytotoxic OA concentrations. We employed an integrative multi-omics approach, encompassing RNA sequencing, shotgun proteomics, phosphoproteomics, and targeted DigiWest analysis. This enabled a detailed exploration of gene and protein expression changes, alongside phosphorylation patterns under OA treatment. The study reveals concentration- and time-dependent deregulation in gene and protein expression, with a significant down-regulation of xenobiotic and lipid metabolism pathways. Up-regulated pathways include actin crosslink formation and a deregulation of apoptotic pathways. Notably, our results revealed that OA, as a potent phosphatase inhibitor, induces alterations in actin filament organization. Phosphoproteomics data highlighted the importance of phosphorylation in enzyme activity regulation, particularly affecting proteins involved in the regulation of the cytoskeleton. OA's inhibition of PP2A further leads to various downstream effects, including alterations in protein translation and energy metabolism. This research expands the understanding of OA's systemic impact, emphasizing its role in modulating the phosphorylation landscape, which influences crucial cellular processes. The results underscore OA's multifaceted effects on the liver, particularly through PP2A inhibition, impacting xenobiotic metabolism, cytoskeletal dynamics, and energy homeostasis. These insights enhance our comprehension of OA's biological significance and potential health risks

Commercial chicken breeds exhibit highly divergent patterns of linkage disequilibrium

The analysis of linkage disequilibrium (LD) underpins the development of effective genotyping technologies, trait mapping and understanding of biological mechanisms such as those driving recombination and the impact of selection. We apply the Malécot-Morton model of LD to create additive LD maps that describe the high-resolution LD landscape of commercial chickens. We investigated LD in chickens (Gallus gallus) at the highest resolution to date for broiler, white egg and brown egg layer commercial lines. There is minimal concordance between breeds of fine-scale LD patterns (correlation coefficient <0.21), and even between discrete broiler lines. Regions of LD breakdown, which may align with recombination hot spots, are enriched near CpG islands and transcription start sites (P<2.2 × 10?16), consistent with recent evidence described in finches, but concordance in hot spot locations between commercial breeds is only marginally greater than random. As in other birds, functional elements in the chicken genome are associated with recombination but, unlike evidence from other bird species, the LD landscape is not stable in the populations studied. The development of optimal genotyping panels for genome-led selection programmes will depend on careful analysis of the LD structure of each line of interest. Further study is required to fully elucidate the mechanisms underlying highly divergent LD patterns found in commercial chickens