DNA Methylation and Histone H1 Jointly Repress Transposable Elements and Aberrant Intragenic Transcripts.

DNA methylation and histone H1 mediate transcriptional silencing of genes and transposable elements, but how they interact is unclear. In plants and animals with mosaic genomic methylation, functionally mysterious methylation is also common within constitutively active housekeeping genes. Here, we show that H1 is enriched in methylated sequences, including genes, of Arabidopsis thaliana, yet this enrichment is independent of DNA methylation. Loss of H1 disperses heterochromatin, globally alters nucleosome organization, and activates H1-bound genes, but only weakly de-represses transposable elements. However, H1 loss strongly activates transposable elements hypomethylated through mutation of DNA methyltransferase MET1. Hypomethylation of genes also activates antisense transcription, which is modestly enhanced by H1 loss. Our results demonstrate that H1 and DNA methylation jointly maintain transcriptional homeostasis by silencing transposable elements and aberrant intragenic transcripts. Such functionality plausibly explains why DNA methylation, a well-known mutagen, has been maintained within coding sequences of crucial plant and animal genes.

Exploring healthcare provider retention in a rural and frontier community in Northern Idaho.

BACKGROUND: A shortage of healthcare providers, particularly in primary care and mental health, exists in the predominately rural state of Idaho. There are also barriers to retaining healthcare providers to work in rural and remote communities. Limited research using U.S. samples has explored factors that may affect the retention of healthcare providers in rural areas. Additionally, due to differences between communities, it is important to conduct community-level investigations to better understand how these factors may affect retention in rural areas. Therefore, the purpose of this study was to explore factors affecting healthcare provider retention in a rural community in Northern Idaho. METHODS: A modified version of the Nursing Community Apgar Questionnaire (NCAQ) was completed by 30 healthcare providers in a rural and frontier community in Northern Idaho to assess factors influencing healthcare provider retention. Factors were classified into classes including geographic, economic, scope of practice, medical support, and facility and community support classes. Retention factors were assessed on their perceived importance to retention as well as whether they were perceived as an advantage or challenge to retention based on Likert scales. A "Community Apgar" score was also created by combining the importance and advantage/challenge factors. RESULTS: Overall, items in the medical support group had the highest importance of any other class and included factors such as nursing workforce. Additionally, the facility and community support class, which included factors such as televideo support, was rated the highest advantage class and had the highest Apgar score, indicating it contained the factor that healthcare providers identified as the most important advantage (i.e., medical reference resources). CONCLUSION: Our study identified multiple factors that healthcare providers deemed as important advantages or disadvantages to retaining healthcare providers in rural areas. Overall, facility and community support factors were found to have the highest advantage in the retention of rural providers. Rural healthcare organizations looking to increase healthcare provider retention should target retention efforts towards these factors. Additional research should also be conducted on other rural samples across the U.S. to make comparisons of findings.

Physician-level determinants of HCV screening during pregnancy in a U.S. sample.

PURPOSE: The purpose of this study was to assess the association between select determinants and HCV screening guideline adherence among physicians who provide prenatal care. RESEARCH QUESTION: What factors may act as determinants of guideline adherence to HCV screening among physicians who provide prenatal care? METHODS: We surveyed a national sample of physicians who provided prenatal care in 2021. The survey included questions from the Clinician Guideline Determinant (CGD) questionnaire, demographic characteristics, and medical practice characteristics. We estimated odds ratios and 95% confidence intervals (CIs) using semi-Bayesian logistic regression for the association between determinants and guideline adherence. RESULTS: Participants included 224 physicians in the United States who reported providing prenatal care. Most physicians practiced in private practice (65%) and the majority were members of the American College of Obstetricians and Gynecologists (ACOG; 91%). Less than half (43%; 95% CI: 36%-49%) of physicians reported regular use of the HCV screening guideline. Physicians who reported general knowledge about HCV (OR = 9.0, 95% CI 3.1-30) or endorsed agreement with ease of implementation (OR = 8.0, 95% CI 2.7-25) had higher odds of adherence to the HCV screening guideline. CONCLUSION: Our study suggests that less than half of practicing prenatal care physicians adhere to HCV screening guidelines for pregnant patients. Our results may be useful as a preliminary screening of select determinants of guideline use for further investigation.

Health Literacy Correlates to HPV Vaccination Among US Adults Ages 27-45.

Human papillomavirus (HPV) vaccination is now available for adults aged 27-45 as a shared clinical decision. Health literacy skills (i.e., accessing, understanding, appraising, applying information) may facilitate vaccine decision-making for adults with a provider recommendation. This study assessed associations between health literacy skills and willingness to get a provider-recommended HPV vaccine among newly eligible US adults. In 2020, US participants (51% women), aged 27-45 years, were surveyed online (n = 691). The outcome was willingness (willing/not willing) to get the HPV vaccine with provider recommendation. Measures were adapted from Sørensen's multidimensional European Health Literacy Scale, which assesses health literacy among four domains (i.e., access, understanding, appraisal, application). Adjusted odds ratios were calculated for the outcome and each health literacy domain, adjusting for personal health determinants (e.g., age, sex). The sample consisted of primarily non-Hispanic (91.2%), White (74.4%), and married (60.7%) adults. Approximately 65% of participants were willing to get a provider-recommended HPV vaccine. Higher willingness to vaccinate with provider recommendation was significantly associated with increased HPV knowledge (understanding; aOR = 1.13, 95% CI 1.04, 1.24), ability to understand HPV information (understanding; aOR = 1.96, 95% CI 1.09, 3.52), increased perceived vulnerability to HPV-related cancer (appraising; aOR = 3.22, 95% CI 1.83, 5.69), and the need for more information on vaccine safety to seek vaccination (applying; aOR = 3.25; 95% CI 2.05, 5.16). Utilizing a multidimensional health literacy framework to evaluate facilitators to HPV vaccination uptake among adults aged 27-45 can help guide future interventions by targeting accurate, easy-to-understand HPV information that connects vaccination efficacy to reduction in HPV cancer risk.

Time-series transcriptomics reveals a BBX32-directed control of acclimation to high light in mature Arabidopsis leaves.

The photosynthetic capacity of mature leaves increases after several days' exposure to constant or intermittent episodes of high light (HL) and is manifested primarily as changes in chloroplast physiology. How this chloroplast-level acclimation to HL is initiated and controlled is unknown. From expanded Arabidopsis leaves, we determined HL-dependent changes in transcript abundance of 3844 genes in a 0-6 h time-series transcriptomics experiment. It was hypothesized that among such genes were those that contribute to the initiation of HL acclimation. By focusing on differentially expressed transcription (co-)factor genes and applying dynamic statistical modelling to the temporal transcriptomics data, a regulatory network of 47 predominantly photoreceptor-regulated transcription (co-)factor genes was inferred. The most connected gene in this network was B-BOX DOMAIN CONTAINING PROTEIN32 (BBX32). Plants overexpressing BBX32 were strongly impaired in acclimation to HL and displayed perturbed expression of photosynthesis-associated genes under LL and after exposure to HL. These observations led to demonstrating that as well as regulation of chloroplast-level acclimation by BBX32, CRYPTOCHROME1, LONG HYPOCOTYL5, CONSTITUTIVELY PHOTOMORPHOGENIC1 and SUPPRESSOR OF PHYA-105 are important. In addition, the BBX32-centric gene regulatory network provides a view of the transcriptional control of acclimation in mature leaves distinct from other photoreceptor-regulated processes, such as seedling photomorphogenesis.

The Evolutionary History of Wild, Domesticated, and Feral Brassica oleracea (Brassicaceae).

Understanding the evolutionary history of crops, including identifying wild relatives, helps to provide insight for conservation and crop breeding efforts. Cultivated Brassica oleracea has intrigued researchers for centuries due to its wide diversity in forms, which include cabbage, broccoli, cauliflower, kale, kohlrabi, and Brussels sprouts. Yet, the evolutionary history of this species remains understudied. With such different vegetables produced from a single species, B. oleracea is a model organism for understanding the power of artificial selection. Persistent challenges in the study of B. oleracea include conflicting hypotheses regarding domestication and the identity of the closest living wild relative. Using newly generated RNA-seq data for a diversity panel of 224 accessions, which represents 14 different B. oleracea crop types and nine potential wild progenitor species, we integrate phylogenetic and population genetic techniques with ecological niche modeling, archaeological, and literary evidence to examine relationships among cultivars and wild relatives to clarify the origin of this horticulturally important species. Our analyses point to the Aegean endemic B. cretica as the closest living relative of cultivated B. oleracea, supporting an origin of cultivation in the Eastern Mediterranean region. Additionally, we identify several feral lineages, suggesting that cultivated plants of this species can revert to a wild-like state with relative ease. By expanding our understanding of the evolutionary history in B. oleracea, these results contribute to a growing body of knowledge on crop domestication that will facilitate continued breeding efforts including adaptation to changing environmental conditions.

The Development and Psychometric Evaluation of the Mid-adult Human Papillomavirus Vaccine Knowledge Scale in the United States.

BACKGROUND: Previous human papillomavirus (HPV) and HPV vaccine knowledge scales have focused on young adults in the vaccination catch-up age range or parents of vaccine eligible adolescents. Previous scales are not specific to the new guidelines for HPV vaccination in mid-adults. The study aimed to develop and validate a mid-adult HPV vaccine knowledge scale informed by the latest vaccine recommendations. METHODS: Self-reported data were collected using a cross-sectional survey of adults aged 27 to 45 years with no history of HPV vaccination (n = 706). Exploratory and confirmatory factor analyses identified latent constructs in a 13-item mid-adult HPV vaccine knowledge scale. Sociodemographic differences in the HPV vaccine knowledge were also assessed. RESULTS: The mean of correct responses across all items was 5.9 (SD, 2.8; range, 0-13). Exploratory and confirmatory factor analyses revealed a 3-factor structure best explained the data with a good construct validity and reliability. The first factor contained 6 items about HPV infection, the second factor contained 3 items about HPV prevention through vaccination, and the third factor contained items about HPV vaccination misinformation. Analysis of variance and t test found significant group level differences in knowledge among sex, race, educational level, annual income, health insurance, and marital status. CONCLUSIONS: Our study supports the use of a knowledge scale for US mid-adults to assess HPV and HPV vaccination knowledge because the patient requires some baseline knowledge of this recommendation to discuss the vaccine with their health care provider. The mid-adult HPV vaccine knowledge scale can measure basic HPV knowledge important to informed decision making.

Correlates of HPV Vaccination Intentions Among Adults Ages 27-45 Years Old in the U.S.

HPV vaccine is recommended for 27-45 year olds in the U.S. based on a shared clinical decision. This study examined knowledge, attitudes, and beliefs of adults 27-45 years old and the association with the likelihood of asking a healthcare provider about the HPV vaccine and the likelihood of getting the HPV vaccine. We conducted a cross-sectional survey of U.S. adults aged 27-45 years between April-May 2020 (n = 691). Primary outcomes were likelihood of asking their provider about the HPV vaccine and likelihood of getting the HPV vaccine. Demographic variables, knowledge, attitudes, and beliefs were covariates. Adjusted models were estimated for each outcome variable with a Poisson distribution and log function. More than half (55.7%) were likely to ask their provider about the HPV vaccine, but less than half (42.9%) were likely to get the HPV vaccine. Likelihood of asking their provider about the HPV vaccine was significantly associated with perceived likelihood of benefitting from the vaccine (aOR = 2.45; 95%CI = 1.69-3.57). Likelihood of receiving the vaccine was associated with attitudes (aOR = 1.04; 95%CI = 1.01-1.07), perceived effectiveness against HPV infection (aOR = 4.03; 95%CI = 1.20-13.53), and perceived likelihood of benefitting from the vaccine (aOR = 4.31; 95%CI = 2.64-7.03). Our findings suggest increasing positive attitudes, perceived effectiveness against infection, and perceived likelihood of benefitting from the vaccination are important factors to address when facilitating a shared clinical decision for HPV vaccination. Understanding factors associated with likelihood of discussing and receiving the HPV vaccine among people aged 27-45 years is important to successfully implement the guidelines for shared clinical decision-making.

Changes in Gene Expression in Space and Time Orchestrate Environmentally Mediated Shaping of Root Architecture.

Shaping of root architecture is a quintessential developmental response that involves the concerted action of many different cell types, is highly dynamic, and underpins root plasticity. To determine to what extent the environmental regulation of lateral root development is a product of cell-type preferential activities, we tracked transcriptomic responses to two different treatments that both change root development in Arabidopsis thaliana at an unprecedented level of temporal detail. We found that individual transcripts are expressed with a very high degree of temporal and spatial specificity, yet biological processes are commonly regulated, in a mechanism we term response nonredundancy. Using causative gene network inference to compare the genes regulated in different cell types and during responses to nitrogen and a biotic interaction, we found that common transcriptional modules often regulate the same gene families but control different individual members of these families, specific to response and cell type. This reinforces that the activity of a gene cannot be defined simply as molecular function; rather, it is a consequence of spatial location, expression timing, and environmental responsiveness.

The Podiatric Medical Profession: A Gender Comparison.

The number of women in podiatric medicine and surgery has increased steadily over the past 4 decades; however, there appears to be a large and continued gender gap with respect to representation in academic medicine and other positions of power. National and state level organizational data were obtained from multiple podiatry professional societies to evaluate the rate at which women achieved leadership roles within the podiatric profession over time. A secondary questionnaire was also developed and electronically mailed to 8684 doctors of podiatric medicine to help capture additional leadership information and to provide further insight into the trends observed. The response rate was 26% (2276/8684). Female representation in academia, research/publications, most leadership positions, and board certifications has increased over time, but at a slower rate than the number of women entering the profession. We observed a decreasing trend of females completing fellowships, speaking at national meetings, becoming residency directors, and receiving American College of Foot and Ankle Surgeons- and American Podiatric Medical Association-sponsored grants/awards. Based on the survey results, female podiatric physicians were more likely to be single, have fewer children, spend more time in a clinical setting, be less satisfied with work, and experience higher work stress levels than their male colleagues. Of the female respondents, 73% described experiencing gender discrimination at some point in their career, and 42% reported experiencing sexual harassment, compared with only 6% and 5% of men, respectively. There continues to be a gender gap in leadership roles, which may be explained partially by work/life balance issues, gender discrimination, and other issues.

Time-Series Transcriptomics Reveals That AGAMOUS-LIKE22 Affects Primary Metabolism and Developmental Processes in Drought-Stressed Arabidopsis.

In Arabidopsis thaliana, changes in metabolism and gene expression drive increased drought tolerance and initiate diverse drought avoidance and escape responses. To address regulatory processes that link these responses, we set out to identify genes that govern early responses to drought. To do this, a high-resolution time series transcriptomics data set was produced, coupled with detailed physiological and metabolic analyses of plants subjected to a slow transition from well-watered to drought conditions. A total of 1815 drought-responsive differentially expressed genes were identified. The early changes in gene expression coincided with a drop in carbon assimilation, and only in the late stages with an increase in foliar abscisic acid content. To identify gene regulatory networks (GRNs) mediating the transition between the early and late stages of drought, we used Bayesian network modeling of differentially expressed transcription factor (TF) genes. This approach identified AGAMOUS-LIKE22 (AGL22), as key hub gene in a TF GRN. It has previously been shown that AGL22 is involved in the transition from vegetative state to flowering but here we show that AGL22 expression influences steady state photosynthetic rates and lifetime water use. This suggests that AGL22 uniquely regulates a transcriptional network during drought stress, linking changes in primary metabolism and the initiation of stress responses.

Differential expression of Lp-PLA2 in obesity and type 2 diabetes and the influence of lipids.

AIMS/HYPOTHESIS: Lipoprotein-associated phospholipase A2 (Lp-PLA2) is a circulatory macrophage-derived factor that increases with obesity and leads to a higher risk of cardiovascular disease (CVD). Despite this, its role in adipose tissue and the adipocyte is unknown. Therefore, the aims of this study were to clarify the expression of Lp-PLA2 in relation to different adipose tissue depots and type 2 diabetes, and ascertain whether markers of obesity and type 2 diabetes correlate with circulating Lp-PLA2. A final aim was to evaluate the effect of cholesterol on cellular Lp-PLA2 in an in vitro adipocyte model. METHODS: Analysis of anthropometric and biochemical variables from a cohort of lean (age 44.4 ± 6.2 years; BMI 22.15 ± 1.8 kg/m2, n = 23), overweight (age 45.4 ± 12.3 years; BMI 26.99 ± 1.5 kg/m2, n = 24), obese (age 49.0 ± 9.1 years; BMI 33.74 ± 3.3 kg/m2, n = 32) and type 2 diabetic women (age 53.0 ± 6.13 years; BMI 35.08 ± 8.6 kg/m2, n = 35), as part of an ethically approved study. Gene and protein expression of PLA2 and its isoforms were assessed in adipose tissue samples, with serum analysis undertaken to assess circulating Lp-PLA2 and its association with cardiometabolic risk markers. A human adipocyte cell model, Chub-S7, was used to address the intracellular change in Lp-PLA2 in adipocytes. RESULTS: Lp-PLA2 and calcium-independent PLA2 (iPLA2) isoforms were altered by adiposity, as shown by microarray analysis (p < 0.05). Type 2 diabetes status was also observed to significantly alter gene and protein levels of Lp-PLA2 in abdominal subcutaneous (AbdSc) (p < 0.01), but not omental, adipose tissue. Furthermore, multivariate stepwise regression analysis of circulating Lp-PLA2 and metabolic markers revealed that the greatest predictor of Lp-PLA2 in non-diabetic individuals was LDL-cholesterol (p = 0.004). Additionally, in people with type 2 diabetes, oxidised LDL (oxLDL), triacylglycerols and HDL-cholesterol appeared important predictors, accounting for 59.7% of the variance (p < 0.001). Subsequent in vitro studies determined human adipocytes to be a source of Lp-PLA2, as confirmed by mRNA expression, protein levels and immunochemistry. Further in vitro experiments revealed that treatment with LDL-cholesterol or oxLDL resulted in significant upregulation of Lp-PLA2, while inhibition of Lp-PLA2 reduced oxLDL production by 19.8% (p < 0.05). CONCLUSIONS/INTERPRETATION: Our study suggests adipose tissue and adipocytes are active sources of Lp-PLA2, with differential regulation by fat depot and metabolic state. Moreover, levels of circulating Lp-PLA2 appear to be influenced by unfavourable lipid profiles in type 2 diabetes, which may occur in part through regulation of LDL-cholesterol and oxLDL metabolism in adipocytes.

Ledipasvir/Sofosbuvir Effectively Treats Hepatitis C Virus Infections in an Underserved Population.

BACKGROUND: Underserved populations have an unequal burden of HCV infections and poor outcomes with interferon-based treatments. Direct-acting antivirals have the potential to reduce these inequalities. AIMS: We aimed to estimate sustained virologic response (SVR) following treatment with sofosbuvir-based regimens for HCV infections among underserved individuals and summarize the frequency of SVR across published studies of underserved populations. METHODS: We used data from a clinical cohort of patients aged ≥ 18 years who initiated sofosbuvir-based regimens for HCV infection between February 2014 and June 2016 at an urban public hospital network that serves as the healthcare safety-net for Tarrant County, Texas. We estimated SVR with corresponding 95% confidence limits (CL). In addition, we systematically reviewed the evidence to identify other studies of direct-acting antivirals among underserved populations. RESULTS: Our study population comprised 435 patients. The majority of patients were aged ≥ 50 years (76%), male (52%), non-Hispanic White (54%), HCV genotype 1 (79%) and treated with ledipasvir/sofosbuvir (69%). Overall SVR was 89% (95% CL 86, 92%) and highest for ledipasvir/sofosbuvir (SVR = 95%, 95% CL 92, 97%). The reported SVR following direct-acting antivirals among 837 underserved patients from three other studies ranged between 90 and 99%. CONCLUSIONS: Our results suggest that direct-acting antivirals, particularly ledipasvir/sofosbuvir, are generally effective for achieving SVR among underserved patients with HCV infections and may help reduce inequalities in HCV prevalence and outcomes for this vulnerable population.

The Ninth Industrial Fluid Properties Simulation Challenge.

The Ninth Industrial Fluid Properties Simulation Challenge aimed to test the ability of molecular modeling approaches to predict water/oil interfacial tension (IFT) at conditions of high temperature and pressure. In particular, the challenge featured water/oil IFT where the oil was n-dodecane, toluene, or a 50:50 n-dodecane/toluene blend at 1.825 MPa and temperatures in the range of 383 K to 443 K. Seven entries were received including approaches such as molecular dynamics (MD) and Monte Carlo (MC) simulations, COSMO-RS, and iSAFT, and they were judged by comparison to pendant drop tensiometer benchmark data. The quality of predictions varied among the entries between approximately 20 % and 70 % of the total points possible with the entries based on MD and MC having the highest scores in most cases. As is often the case in molecular modeling, predictions of the relative trends tended to be reliable even if the absolute values were not.

The transcription factor Maf-S regulates metabolic resistance to insecticides in the malaria vector Anopheles gambiae.

BACKGROUND: Malaria control in Africa is dependent upon the use insecticides but intensive use of a limited number of chemicals has led to resistance in mosquito populations. Increased production of enzymes that detoxify insecticides is one of the most potent resistance mechanisms. Several metabolic enzymes have been implicated in insecticide resistance but the processes controlling their expression have remained largely elusive. RESULTS: Here, we show that the transcription factor Maf-S regulates expression of multiple detoxification genes, including the key insecticide metabolisers CYP6M2 and GSTD1 in the African malaria vector Anopheles gambiae. Attenuation of this transcription factor through RNAi induced knockdown reduced transcript levels of these effectors and significantly increased mortality after exposure to the pyrethroid insecticides and DDT (permethrin: 9.2% to 19.2% (p = 0.015), deltamethrin: 3.9% to 21.6% (p = 0.036) and DDT: 1% to 11.7% (p = <0.01), whilst dramatically decreasing mortality induced by the organophosphate malathion (79.6% to 8.0% (p = <0.01)). Additional genes regulated by Maf-S were also identified providing new insight into the role of this transcription factor in insects. CONCLUSION: Maf-S is a key regulator of detoxification genes in Anopheles mosquitoes. Disrupting this transcription factor has opposing effects on the mosquito's response to different insecticide classes providing a mechanistic explanation to the negative cross resistance that has been reported between pyrethroids and organophosphates.

Loss of Endometrial Plasticity in Recurrent Pregnancy Loss.

Menstruation drives cyclic activation of endometrial progenitor cells, tissue regeneration, and maturation of stromal cells, which differentiate into specialized decidual cells prior to and during pregnancy. Aberrant responsiveness of human endometrial stromal cells (HESCs) to deciduogenic cues is strongly associated with recurrent pregnancy loss (RPL), suggesting a defect in cellular maturation. MeDIP-seq analysis of HESCs did not reveal gross perturbations in CpG methylation in RPL cultures, although quantitative differences were observed in or near genes that are frequently deregulated in vivo. However, RPL was associated with a marked reduction in methylation of defined CA-rich motifs located throughout the genome but enriched near telomeres. Non-CpG methylation is a hallmark of cellular multipotency. Congruently, we demonstrate that RPL is associated with a deficiency in endometrial clonogenic cell populations. Loss of epigenetic stemness features also correlated with intragenic CpG hypomethylation and reduced expression of HMGB2, coding high mobility group protein 2. We show that knockdown of this sequence-independent chromatin protein in HESCs promotes senescence and impairs decidualization, exemplified by blunted time-dependent secretome changes. Our findings indicate that stem cell deficiency and accelerated stromal senescence limit the differentiation capacity of the endometrium and predispose for pregnancy failure.

Comparative genomic, proteomic and exoproteomic analyses of three Pseudomonas strains reveals novel insights into the phosphorus scavenging capabilities of soil bacteria.

Bacteria that inhabit the rhizosphere of agricultural crops can have a beneficial effect on crop growth. One such mechanism is the microbial-driven solubilization and remineralization of complex forms of phosphorus (P). It is known that bacteria secrete various phosphatases in response to low P conditions. However, our understanding of their global proteomic response to P stress is limited. Here, exoproteomic analysis of Pseudomonas putida BIRD-1 (BIRD-1), Pseudomonas fluorescens SBW25 and Pseudomonas stutzeri DSM4166 was performed in unison with whole-cell proteomic analysis of BIRD-1 grown under phosphate (Pi) replete and Pi deplete conditions. Comparative exoproteomics revealed marked heterogeneity in the exoproteomes of each Pseudomonas strain in response to Pi depletion. In addition to well-characterized members of the PHO regulon such as alkaline phosphatases, several proteins, previously not associated with the response to Pi depletion, were also identified. These included putative nucleases, phosphotriesterases, putative phosphonate transporters and outer membrane proteins. Moreover, in BIRD-1, mutagenesis of the master regulator, phoBR, led us to confirm the addition of several novel PHO-dependent proteins. Our data expands knowledge of the Pseudomonas PHO regulon, including species that are frequently used as bioinoculants, opening up the potential for more efficient and complete use of soil complexed P.

A virulent strain of deformed wing virus (DWV) of honeybees (Apis mellifera) prevails after Varroa destructor-mediated, or in vitro, transmission.

The globally distributed ectoparasite Varroa destructor is a vector for viral pathogens of the Western honeybee (Apis mellifera), in particular the Iflavirus Deformed Wing Virus (DWV). In the absence of Varroa low levels DWV occur, generally causing asymptomatic infections. Conversely, Varroa-infested colonies show markedly elevated virus levels, increased overwintering colony losses, with impairment of pupal development and symptomatic workers. To determine whether changes in the virus population were due Varroa amplifying and introducing virulent virus strains and/or suppressing the host immune responses, we exposed Varroa-naïve larvae to oral and Varroa-transmitted DWV. We monitored virus levels and diversity in developing pupae and associated Varroa, the resulting RNAi response and transcriptome changes in the host. Exposed pupae were stratified by Varroa association (presence/absence) and virus levels (low/high) into three groups. Varroa-free pupae all exhibited low levels of a highly diverse DWV population, with those exposed per os (group NV) exhibiting changes in the population composition. Varroa-associated pupae exhibited either low levels of a diverse DWV population (group VL) or high levels of a near-clonal virulent variant of DWV (group VH). These groups and unexposed controls (C) could be also discriminated by principal component analysis of the transcriptome changes observed, which included several genes involved in development and the immune response. All Varroa tested contained a diverse replicating DWV population implying the virulent variant present in group VH, and predominating in RNA-seq analysis of temporally and geographically separate Varroa-infested colonies, was selected upon transmission from Varroa, a conclusion supported by direct injection of pupae in vitro with mixed virus populations. Identification of a virulent variant of DWV, the role of Varroa in its transmission and the resulting host transcriptome changes furthers our understanding of this important viral pathogen of honeybees.

The clock protein period 2 synchronizes mitotic expansion and decidual transformation of human endometrial stromal cells.

Implantation requires coordinated interactions between the conceptus and surrounding decidual cells, but the involvement of clock genes in this process is incompletely understood. Circadian oscillations are predicated on transcriptional-translational feedback loops, which balance the activities of the transcriptional activators CLOCK (circadian locomotor output cycles kaput) and brain muscle arnt-like 1 and repressors encoded by PER (Period) and Cryptochrome genes. We show that loss of PER2 expression silences circadian oscillations in decidualizing human endometrial stromal cells (HESCs). Down-regulation occurred between 12 and 24 hours following differentiation and coincided with reduced CLOCK binding to a noncanonical E-box enhancer in the PER2 promoter. RNA sequencing revealed that premature inhibition of PER2 by small interfering RNA knockdown leads to a grossly disorganized decidual response. Gene ontology analysis highlighted a preponderance of cell cycle regulators among the 1121 genes perturbed upon PER2 knockdown. Congruently, PER2 inhibition abrogated mitotic expansion of differentiating HESCs by inducing cell cycle block at G2/M. Analysis of 70 midluteal endometrial biopsies revealed an inverse correlation between PER2 transcript levels and the number of miscarriages in women suffering reproductive failure (Spearman rank test, ρ = -0.3260; P = 0.0046). Thus, PER2 synchronizes endometrial proliferation with initiation of aperiodic decidual gene expression; uncoupling of these events may cause recurrent pregnancy loss.

Does selection for gamete dispersal and capture lead to a sex difference in clump water-holding capacity?

PREMISE OF THE STUDY: Differences in male and female reproductive function can lead to selection for sex-specific gamete dispersal and capture traits. These traits have been explored from shoot to whole plant levels in wind-pollinated species. While shoot traits have been explored in water-fertilized species, little is known about how whole plant morphology affects gamete dispersal and capture. We used the dioecious, water-fertilized plant Bryum argenteum to test for differences in clump morphology and water-holding characteristics consistent with divergent selection. We hypothesized that sex-specific clump morphology, arising at maturity, produces relatively low male water-holding capacity for gamete dispersal and high female capacity for gamete capture. METHODS: We measured isolated young shoot and clump water-holding capacity and clump morphological characteristics on greenhouse-grown plants. Young shoot capacity was used to predict clump capacity, which was compared with actual clump capacity. KEY RESULTS: Young male shoots held more water per unit length, and male clumps had higher shoot density, which extrapolated to higher clump water-holding capacity. However, female clumps held more water and were taller with more robust shoots. Actual clump capacity correlated positively with clump height and shoot cross-sectional area. CONCLUSIONS: The sex difference in actual clump capacity and its unpredictability from younger shoots are consistent with our hypothesis that males should hold less water than females to facilitate sexual reproduction. These results provide conceptual connections to other plant groups and implications for connecting divergent selection to female-biased sex ratios in B. argenteum and other bryophytes.