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Abstract Background Fruits, with their diverse shapes, colors, and flavors, represent a fascinating aspect of plant evolution and have played a significant role in human history and nutrition. Understanding the origins and evolutionary pathways of fruits offers valuable insights into plant diversity, ecological relationships, and the development of agricultural systems. Arabidopsis thaliana (Brassicaceae, core eudicot) and Eschscholzia californica (California poppy, Papaveraceae, sister group to core eudicots) both develop dry dehiscent fruits, with two valves separating explosively from the replum-like region upon maturation. This led to the hypothesis, that homologous gene regulatory networks direct fruit development and dehiscence in both species. Results Transcriptome analysis of separately collected valve and replum-like tissue of California poppy yielded the SEEDSTICK (STK) ortholog as candidate for dehiscence zone regulation. Expression analysis of STK orthologs from dry dehiscing fruits of legumes (Vicia faba, Glycine max and Pisum sativum) shows their involvement in fruit development. Functional analysis using Virus-Induced Gene Silencing (VIGS) showed premature rupture of fruits and clarified the roles of EscaSTK: an evolutionary conserved role in seed filling and seed coat development, and a novel role in restricting cell divisions in the inner cell layer of the valve. Conclusion Our analysis shows that the gene regulatory network described in Arabidopsis is significantly different in other dicots, even if their fruits form a dehiscence zone at the valve margins. The ortholog of STK, known to be involved in ovule development and seed abscission in Arabidopsis, was recruited to a network regulating fruit wall proliferation in California poppy. There, EscaSTK allows fruit maturation without premature capsule rupture, highlighting the importance of proper endocarp development for successful seed dispersal.

Abstract Background Inpatient rehabilitation therapies can be applied for in Germany by patients of working age to support their return to work. However, there are some problems that impede an easy and uncomplicated application process. An interdisciplinary case management approach for rehabilitation care planning was developed to facilitate the access to rehabilitation. Case conferences (CCs) were held with relevant stakeholders and took place on a digital communication platform. We conducted a qualitative process evaluation to understand the implementation of the intervention and to identify contextual factors as well as mechanisms for a successful implementation in the context of primary care. Methods The process evaluation included interviews with primary care physicians (PCPs), patients and stakeholders involved in the intervention process. Reflexive thematic analysis was used to analyse the data. Emerging themes were structured according to the Donabedian framework of structure, process and outcomes. Results A total of 18 interviews were conducted. Important results included the desire for more patient involvement and case management. Patients especially valued the opportunity to receive support from a social worker. Limitations of the platform related to usability and limited opportunities for stakeholder communication. Despite training for PCPs, several problems arose regarding the clarity of the intervention process. Patients were satisfied with their application process and the treatments offered, while PCPs reported an increase in workload. Conclusions A digitalisation of the application procedure for rehabilitation and further treatment options is acceptable to patients and personal support of a social worker is particularly valued. However, patients should be included in the CC in terms of a shared decision-making process. The digital platform requires sufficient training and adjustments have to be made to enhance usability and to improve the efficiency of the process for PCPs. Overall, the exchange between the various stakeholders in the CC is considered particularly useful in more complex cases. Trial registration DRKS German Clinical Trials Register, DRKS0 00242 07. Registered on 22 March 2021.

Abstract Background Chronic diseases are a significant and growing problem of our time. They impair the ability to work and increase the risk of early retirement. To support the return to work, rehabilitation services can be applied for in Germany. Currently, the application system for rehabilitation allows only a limited degree of individualisation of the treatment and is associated with a lack of multidisciplinary communication. To facilitate rehabilitation care planning, we developed a complex intervention. A digital, platform-based case management approach (intervention) will ensure multidisciplinary communication and the tailored selection of medical treatments and/or non-medical support measures. The overall objective is to assess the effectiveness of the intervention compared to treatment as usual (control condition). The German Federal Ministry of Labour and Social Affairs (BMAS) funds the RehaPro-SERVE study (grant number: 661R0053K1). Methods This is the protocol for an investigator-initiated, pragmatic, multicentre, randomised and controlled two-arm parallel-group superiority trial with embedded qualitative process evaluation. The study will be conducted in Hesse state, Germany. N = 59 primary care physicians will be recruited and tasked with the recruitment of six eligible patients each. Eligibility criteria: age 40–60; minimum of 4-week work disability due to musculoskeletal, oncologic or psychological conditions or the post-COVID-19 syndrome within the last 6 months; at high risk for early retirement. In total, n = 352 patients will be randomised with a 1:1 allocation to intervention or control group and stratified by primary care practice using permuted blocks. The primary outcome is the number of days of sick leave during a 12-month period after the assumed completion of treatments (t1 to t2). Secondary outcomes include the number of days of sick leave (self-report), work ability, and health-related quality of life, as well as data from the qualitative process evaluation. Discussion The results of the study will inform the design of future care services and provide valuable information on multidisciplinary case management in the context of rehabilitation care planning. The results of the qualitative process evaluation will further contribute to the understanding of facilitating and hindering factors. Trial registration DRKS-German Clinical Trials Register, DRKS0 00242 07. Registered on 22 March 2021.

Abstract Deprescribing of inappropriate long-term proton pump inhibitors (PPI) is challenging and there is a lack of useful methods for general practitioners to tackle this. The objective of this randomized controlled trial was to evaluate the effectiveness of the electronic decision aid tool arriba-PPI on reduction of long-term PPI intake. Participants (64.5 ± 12.9 years; 54.4% women) with a PPI intake of at least 6 months were randomized to receive either consultation with arriba-PPI from their general practitioner (n = 1256) or treatment as usual (n = 1131). PPI prescriptions were monitored 6 months before, 6 and 12 months after study initiation. In 49.2% of the consultations with arriba-PPI, the general practitioners and their patients made the decision to reduce or discontinue PPI intake. At 6 months, there was a significant reduction by 22.3% (95% CI 18.55 to 25.98; p

Abstract The Arabidopsis thaliana Receptor-Like Protein RLP30 contributes to immunity against the fungal pathogen Sclerotinia sclerotiorum. Here we identify the RLP30-ligand as a small cysteine-rich protein (SCP) that occurs in many fungi and oomycetes and is also recognized by the Nicotiana benthamiana RLP RE02. However, RLP30 and RE02 share little sequence similarity and respond to different parts of the native/folded protein. Moreover, some Brassicaceae other than Arabidopsis also respond to a linear SCP peptide instead of the folded protein, suggesting that SCP is an eminent immune target that led to the convergent evolution of distinct immune receptors in plants. Surprisingly, RLP30 shows a second ligand specificity for a SCP-nonhomologous protein secreted by bacterial Pseudomonads. RLP30 expression in N. tabacum results in quantitatively lower susceptibility to bacterial, fungal and oomycete pathogens, thus demonstrating that detection of immunogenic patterns by Arabidopsis RLP30 is involved in defense against pathogens from three microbial kingdoms.

Abstract Background To evaluate patients’ perspectives and their experiences with a consultation involving a computer-assisted and patient-centered discontinuation strategy (arriba-PPI tool) as part of a German multicenter study on reducing the prescription of proton pump inhibitors (PPIs). Methods Qualitative in-depth telephone interviews on proton pump inhibitors with patients who had received an arriba-PPI tool-based counseling by their general practitioner (GP). A random sample of 30 patients was taken from study participants. Interviews were conducted in 2020 and analyzed using a thematic qualitative text analysis. Results Although this was meant to be the key to shared decision making with regard to PPI reduction, study participants mostly did not recall the visual features of the tool. However, a few patients remembered them very clearly. Above all, patients appreciated a trustful relationship with the GP as well as comprehensive, individualized counseling. Conclusion Application of the arriba-PPI tool can support the decision process but can also hinder the consultation process if the tool is not properly embedded in the consultation. GPs using the arriba-PPI tool to support the shared decision-making process should consider the patients’ and their own expectations on the benefit of the visual representation of the tool.

California poppy or golden poppy (Eschscholzia californica) is the iconic state flower of California, with native ranges from Northern California to Southwestern Mexico. It grows well as an ornamental plant in Mediterranean climates, but it might be invasive in many parts of the world. California poppy was also highly prized by Native Americans for its medicinal value, mainly due to its various specialized metabolites, especially benzylisoquinoline alkaloids (BIAs). As a member of the Ranunculales, the sister lineage of core eudicots it occupies an interesting phylogenetic position. California poppy has a short-lived life cycle but can be maintained as a perennial. It has a comparatively simple floral and vegetative morphology. Several genetic resources, including options for genetic manipulation and a draft genome sequence have been established already with many more to come. Efficient cell and tissue culture protocols are established to study secondary metabolite biosynthesis and its regulation. Here, we review the use of California poppy as a model organism for plant genetics, with particular emphasis on the evolution of development and BIA biosynthesis. In the future, California poppy may serve as a model organism to combine two formerly separated lines of research: the regulation of morphogenesis and the regulation of secondary metabolism. This can provide insights into how these two integral aspects of plant biology interact with each other.

Abstract Background Long-term disability to work is a risk factor for a permanent reduction in income. Rehabilitation care can support people to return to work. In Germany, rehabilitation care to return to work is mostly provided in specialised clinics. The aim of the Rehapro-SERVE study is to reduce work disability days by facilitating rehabilitation care planning using a digital communication platform. To investigate the feasibility, we will test the implementation of the digital platform and evaluate the study procedures. The Rehapro-SERVE study is funded by the German Federal Ministry of Labour and Social Affairs (BMAS) (grant number: 661R0053K1). Method The feasibility study includes a two-armed unblinded block randomised controlled study (RCT) without follow-up assessments as well as an interview study. Participants for the RCT (n = 16) are primary care patients with a minimum of 4 weeks of absence from work due to musculoskeletal, oncological or psychological conditions and at high risk of early retirement. Eligibility criteria are age 40 to 60 years; minimum of 4 weeks continuous sick leave before recruitment due to musculoskeletal, mental health or oncological conditions; and being at high risk of early retirement. Patients will be recruited from 8 primary care practices in urban and rural areas in Hesse, Germany. Following baseline assessments, patients will be randomised to either digitalised care planning (treatment) or a control group. The digitalised care planning platform will include the patients’ primary care physicians, jobcentres and public health physicians to decide on a tailored return-to-work programme. The collaboration will be supported by a case administrator and, if considered beneficial, a social worker for the patient. An interview study will evaluate the acceptability of the study procedures and the intervention. Discussion The use of a digital communication platform enables stakeholders to exchange information and discuss rehabilitation care planning in a timely fashion. The results of the feasibility study will lead to the adaptation of study procedures for the main study. The results will support the design and conduct of similar studies including digital applications in primary care or across different healthcare settings. Trial registration DRKS - German Clinical Trials Register, DRKS00024207 . Registered on 22 March 2021

The important worldwide forage crop red clover (Trifolium pratense L.) is widely cultivated as cattle feed and for soil improvement. Wild populations and landraces have great natural diversity that could be used to improve cultivated red clover. However, to date, there is still insufficient knowledge about the natural genetic and phenotypic diversity of the species. Here, we developed a low-cost complexity reduced mRNA analysis (mRNA-GBS) and compared the results with population genetic (GBS) and previously published mRNA-Seq data, to assess whether analysis of intraspecific variation within and between populations and transcriptome responses is possible simultaneously. The mRNA-GBS approach was successful. SNP analyses from the mRNA-GBS approach revealed comparable patterns to the GBS results, but due to site-specific multifactorial influences of environmental responses as well as conceptual and methodological limitations of mRNA-GBS, it was not possible to link transcriptome analyses with reduced complexity and sequencing depth to previously published greenhouse and field expression studies. Nevertheless, the use of short sequences upstream of the poly(A) tail of mRNA to reduce complexity are promising approaches that combine population genetics and expression profiling to analyze many individuals with trait differences simultaneously and cost-effectively, even in non-model species. Nevertheless, our study design across different regions in Germany was also challenging. The use of reduced complexity differential expression analyses most likely overlays site-specific patterns due to highly complex plant responses under natural conditions.

Abstract Background Cough is a relevant reason for encounter in primary care. For evidence-based decision making, general practitioners need setting-specific knowledge about prevalences, pre-test probabilities, and prognosis. Accordingly, we performed a systematic review of symptom-evaluating studies evaluating cough as reason for encounter in primary care. Methods We conducted a search in MEDLINE and EMBASE. Eligibility criteria and methodological quality were assessed independently by two reviewers. We extracted data on prevalence, aetiologies and prognosis, and estimated the variation across studies. If justifiable in terms of heterogeneity, we performed a meta-analysis. Results We identified 21 eligible studies on prevalence, 12 on aetiology, and four on prognosis. Prevalence/incidence estimates were 3.8–4.2%/12.5% (Western primary care) and 10.3–13.8%/6.3–6.5% in Africa, Asia and South America. In Western countries the underlying diagnoses for acute cough or cough of all durations were respiratory tract infections (73–91.9%), influenza (6–15.2%), asthma (3.2–15%), laryngitis/tracheitis (3.6–9%), pneumonia (4.0–4.2%), COPD (0.5–3.3%), heart failure (0.3%), and suspected malignancy (0.2–1.8%). Median time for recovery was 9 to 11 days. Complete recovery was reported by 40.2- 67% of patients after two weeks, and by 79% after four weeks. About 21.1–35% of patients re-consulted; 0–1.3% of acute cough patients were hospitalized, none died. Evidence is missing concerning subacute and chronic cough. Conclusion Prevalences and incidences of cough are high and show regional variation. Acute cough, mainly caused by respiratory tract infections, is usually self-limiting (supporting a “wait-and-see” strategy). We have no setting-specific evidence to support current guideline recommendations concerning subacute or chronic cough in Western primary care. Our study presents epidemiological data under non non-pandemic conditions. It will be interesting to compare these data to future research results of the post-pandemic era.

Abstract Background For evidence-based decision making, primary care physicians need to have specific and reliable information on the pre-test probabilities of underlying diseases and a symptom’s course. We performed a systematic review of symptom-evaluating studies in primary care, following three research questions: (1) What is the prevalence of the symptom cough in children consulting primary care physicians? (2) What are the underlying aetiologies of cough and the respective frequencies? (3) What is the prognosis of children with cough? Methods Following a pre-defined algorithm and independent double reviewer ratings we searched MEDLINE and EMBASE. All quantitative original research articles in English, French or German were included if they focused on unselected study populations of children consulting a primary care physician for cough. We used the random effects model for meta-analysis in subgroups, if justifiable in terms of heterogeneity. Results We identified 14 eligible studies on prevalence, five on aetiology and one on prognosis. Prevalence estimates varied between 4.7 and 23.3% of all reasons for an encounter, or up to estimates of 60% when related to patients or consultations. Cough in children is more frequent than in adults, with lowest prevalences in adolescents and in summer. Acute cough is mostly caused by upper respiratory tract infections (62.4%) and bronchitis (33.3%); subacute or chronic cough by recurrent respiratory tract infection (27.7%), asthma (up to 50.4% in cough persisting more than 3 weeks), and pertussis (37.2%). Potentially serious diseases like croup, pneumonia or tuberculosis are scarce. In children with subacute and chronic cough the total duration of cough ranged from 24 to 192 days. About 62.3% of children suffering from prolonged cough are still coughing two months after the beginning of symptoms. Conclusion Cough is one of the most frequent reasons for an encounter in primary care. Our findings fit in with current guideline recommendations supporting a thoughtful wait-and-see approach in acute cough and a special awareness in chronic cough of the possibility of asthma and pertussis. Further evidence of aetiological pre-test probabilities is needed to assess the diagnostic gain based on patient history and clinical signs for differential diagnoses of cough in children.

Abstract Background Red clover (Trifolium pratense) is globally used as a fodder plant due its high nutritional value and soil improving qualities. In response to mowing, red clover exhibits specific morphological traits to compensate the loss of biomass. The morphological reaction is well described, but the underlying molecular mechanisms and its role for plants grown in the field are unclear. Results Here, we characterize the global transcriptional response to mowing of red clover by comparing plants grown under greenhouse conditions with plants growing on agriculturally used fields. Unexpectedly, we found that biotic and abiotic stress related changes of plants grown in the field overlay their regrowth related transcriptional changes and characterized transcription related protein families involved in these processes. Further, we can show that gibberellins, among other phytohormones, also contribute to the developmental processes related to regrowth after biomass-loss. Conclusions Our findings show that massive biomass loss triggers less transcriptional changes in field grown plants than their struggle with biotic and abiotic stresses and that gibberellins also play a role in the developmental program related to regrowth after mowing in red clover. Our results provide first insights into the physiological and developmental processes of mowing on red clover and may serve as a base for red clover yield improvement.

Abstract Background Plant development is controlled by the action of many, often connected gene regulatory networks. Differential gene expression controlled by internal and external cues is a major driver of growth and time specific differentiation in plants. Transcriptome analysis is the state-of-the-art method to detect spatio-temporal changes in gene expression during development. Monitoring changes in gene expression at early stages or in small plant organs and tissues requires an accurate technique of tissue isolation, which subsequently results in RNA of sufficient quality and quantity. Laser-microdissection enables such accurate dissection and collection of desired tissue from sectioned material at a microscopic level for RNA extraction and subsequent downstream analyses, such as transcriptome, proteome, genome or miRNA. Results A protocol for laser-microdissection, RNA extraction and RNA-seq was optimized and verified for three distant angiosperm species: Arabidopsis thaliana (Brassicaceae), Oryza sativa (Poaceae) and Eschscholzia californica (Papaveraceae). Previously published protocols were improved in processing speed by reducing the vacuum intensity and incubation time during tissue fixation and incubation time and cryoprotection and by applying adhesive tape. The sample preparation and sectioning of complex and heterogenous flowers produced adequate histological quality and subsequent RNA extraction from micro-dissected gynoecia reliably generated samples of sufficient quality and quantity on all species for RNA-seq. Expression analysis of growth stage specific A. thaliana and O. sativa transcriptomes showed distinct patterns of expression of chromatin remodelers on different time points of gynoecium morphogenesis from the initiation of development to post-meiotic stages. Conclusion Here we describe a protocol for plant tissue preparation, cryoprotection, cryo-sectioning, laser microdissection and RNA sample preparation for Illumina sequencing of complex plant organs from three phyletically distant plant species. We are confident that this approach is widely applicable to other plant species to enable transcriptome analysis with high spatial resolution in non-model plant species. The protocol is rapid, produces high quality sections of complex organs and results in RNA of adequate quality well suited for RNA-seq approaches. We provide detailed description of each stage of sample preparation with the quality and quantity measurements as well as an analysis of generated transcriptomes.

Abstract Background Proton pump inhibitors (PPIs) are increasingly being prescribed, although long-term use is associated with multiple side effects. Therefore, an electronic decision support tool with the aim of reducing the long-term use of PPIs in a shared decision-making process between general practitioners (GPs) and their patients has been developed. The developed tool is a module that can be added to the so-called arriba decision support tool, which is already used by GPs in Germany in routine care. In this large-scale cluster-randomized controlled trial we evaluate the effectiveness of this arriba-PPI tool. Methods The arriba-PPI tool is an electronic decision support system that supports shared decision-making and evidence-based decisions around the long-term use of PPIs at the point of care. The tool will be evaluated in a cluster-randomized controlled trial involving 210 GP practices and 3150 patients in Germany. GP practices will be asked to recruit 20 patients aged ≥ 18 years regularly taking PPIs for ≥ 6 months. After completion of patient recruitment, each GP practice with enrolled patients will be cluster-randomized. Intervention GP practices will get access to the software arriba-PPI, whereas control GPs will treat their patients as usual. After an observation period of six months, GP practices will be compared regarding the reduction of cumulated defined daily doses of PPI prescriptions per patient. Discussion Our principal hypothesis is that the application of the arriba-PPI tool can reduce PPI prescribing in primary care by at least 15% compared to conventional strategies used by GPs. A positive result implies the implementation of the arriba-PPI tool in routine care. Trial registration German Clinical Trials Register, DRKS00016364. Registered on 31 January 2019.

Plants react to various biotic and abiotic factors by adjusting their growth pattern. This process, called phenotypic plasticity, can also be observed in the agronomical important fodder plant Trifolium pratense L. (red clover) which is grown worldwide for its high pro-tein content and soil improving ability. After cutting it changes its growth pattern due to phenotypic plasticity and initiates a second growth phase. Here, we analyze the regrowth dynamics of red clover in response to grazing or mowing by recording the plant’s architecture, leaf morphology, and growth performance in different cutting experiments. As previous studies were limited in the number of individuals and carried out via common garden experiments, we analyzed the regrowth reaction of T. pratense under standard agricul-tural field conditions. T. pratense forms smaller and rounder leaflets after repeated cutting, compensated by the production of more bio-mass. Nitrogen contents were subjected to seasonal changes, rather than by changes through cutting. As middle to late cut plants had higher regrowth capacities and regrew more biomass than early cut plants, an optimal time point for biomass harvest can be suggested to maximize the total yield of red clover biomass.

Constitutive heterochromatin is considered as a functionally inert genome compartment, important for its architecture and stability. How such stable structure is maintained is not well understood. Here, we apply four different visualization schemes to label it and investigate its dynamics during DNA replication and repair. We show that replisomes assemble over the heterochromatin in a temporally ordered manner. Furthermore, heterochromatin undergoes transient decompaction locally at the active sites of DNA synthesis. Using selective laser microirradiation conditions that lead to damage repaired via processive DNA synthesis, we measured similarly local decompaction of heterochromatin. In both cases, we could not observe large-scale movement of heterochromatin to the domain surface. Instead, the processive DNA synthesis machinery assembled at the replication/repair sites. Altogether, our data are compatible with a progression of DNA replication/repair along the chromatin in a dynamic mode with localized and transient decompaction that does not globally remodels the whole heterochromatin compartment.

Abstract Background Dizziness is a common reason for consulting a general practitioner and there is a broad range of possible underlying aetiologies. There are few evidence-based data about prevalence, aetiology and prognosis in primary care. We aimed to conduct a systematic review of symptom-evaluating studies on prevalence, aetiology or prognosis of dizziness in primary care. Methods We systematically searched MEDLINE and EMBASE. Two independent researchers screened titles and abstracts according to predefined criteria. We included all studies evaluating the symptoms ‘dizziness’ or ‘vertigo’ as a reason for consultation in primary care. We extracted data about study population and methodology and prevalence, aetiology and prognosis. Two raters independently judged study quality and risk of bias. We investigated the variation across studies using forest plots, I2 and prediction intervals. Since we anticipated a great amount of clinical and unexplained statistical heterogeneity, we provided qualitative syntheses instead of pooled estimates. Results We identified 31 studies (22 on prevalence, 14 on aetiology and 8 on prognosis). Consultation prevalence differs between 1,0 and 15,5%. The most common aetiologies are vestibular/peripheral (5,4-42,1%), benign peripheral positional vertigo (4,3-39,5%), vestibular neuritis (0,6-24,0%), Menière’s disease (1,4-2,7%), cardiovascular disease (3,8-56,8%), neurological disease (1,4-11,4%), psychogenic (1,8-21,6%), no clear diagnosis (0,0-80,2%). While studies based on subjective patient assessment reported improvement rates from 37 to 77%, these findings could not be confirmed when applying instruments that measure symptom severity or quality of life. Conclusion There is a broad variety of possible underlying diseases for the symptom dizziness. There exist only few methodologically sound studies concerning aetiology and prognosis of dizziness.

Abstract Insect-derived antifungal peptides have a significant economic potential, particularly for the engineering of pathogen-resistant crops. However, the nonspecific antifungal activity of such peptides could result in detrimental effects against beneficial fungi, whose interactions with plants promote growth or increase resistance against biotic and abiotic stress. The antifungal peptide metchnikowin (Mtk) from Drosophila melanogaster acts selectively against pathogenic Ascomycota, including Fusarium graminearum, without affecting Basidiomycota such as the beneficial symbiont Piriformospora indica. Here we investigated the mechanism responsible for the selective antifungal activity of Mtk by using the peptide to probe a yeast two-hybrid library of F. graminearum cDNAs. We found that Mtk specifically targets the iron-sulfur subunit (SdhB) of succinate–coenzyme Q reductase (SQR). A functional assay based on the succinate dehydrogenase (SDH) activity of mitochondrial complex II clearly demonstrated that Mtk inhibited the SDH activity of F. graminearum mitochondrial SQR by up to 52%, but that the equivalent enzyme in P. indica was unaffected. A phylogenetic analysis of the SdhB family revealed a significant divergence between the Ascomycota and Basidiomycota. SQR is one of the key targets of antifungal agents and we therefore propose Mtk as an environmentally sustainable and more selective alternative to chemical fungicides.

Floral meristems are dynamic systems that generate floral organ primordia at their flanks and, in most species, terminate while giving rise to the gynoecium primordia. However, we find species with floral meristems that generate additional ring meristems repeatedly throughout angiosperm history. Ring meristems produce only stamen primordia, resulting in polystemous flowers (having stamen numbers more than double that of petals or sepals), and act independently of the floral meristem activity. Most of our knowledge on floral meristem regulation is derived from molecular genetic studies of Arabidopsis thaliana, a species with a fixed number of floral organs and, as such of only limited value for understanding ring meristem function, regulation, and ecological value. This review provides an overview of the main molecular players regulating floral meristem activity in A. thaliana and summarizes our knowledge of ring primordia morphology and occurrence in dicots. Our work provides a first step toward understanding the significance and molecular genetics of ring meristem regulation and evolution.

Background The establishment of a medical education program in the rural area of Siegen is planned to be the first step against a shortage of physicians in this region. General practitioners (GPs) will be extensively involved in this program as Family Medicine (Allgemeinmedizin) will become a core subject in the curriculum nationwide. Based on this situation we aim to figure out GPs motivation to participate in medical education. For this purpose, we had to construct and test a new questionnaire. Methods A survey was conducted among general practitioners (GPs) in the region of Siegen-Wittgenstein regarding their motivation to participate in medical education. For this purpose, the Motivation for Medical Education Questionnaire (MoME-Q), a 24-item questionnaire, was developed. Structural characteristics of GPs, the Maslach Burnout Inventory (MBI) and the Work Satisfaction Questionnaire (WSQ) were used for validation purposes. Results A representative number of GPs took part in the study (53.8%). Although the majority had no connection to a university (86%), 83% can imagine participating in the education of medical students. The items of the MoME-Q load on two factors (commitment and personal benefit). The confirmatory factor analysis shows a good model fit. Subscales of the MoME-Q were able to differentiate between physicians with and without authorization to train GP residents, between practices with and without a specialized practice nurse, and between physicians with and without previous experience in medical education. The MoME-Q subscale “commitment” correlated significantly with all three subscales of the MBI. Correlations were in the medium range around |.30|. Conclusion The MoME-Q seems to be an appropriate tool to assess motivation to participate in medical education of GPs. In our sample, a large number of GPs was motivated to participate in the education of medical students. Future studies with larger number of GPs should be carried out to validate and confirm our findings. Whether the MoME-Q is also appropriate for other specialties should also be shown in further empirical studies.

One of the crucial steps in the life cycle of angiosperms is the development of carpels. They are the most complex plant organs, harbor the seeds, and, after fertilization, develop into fruits and are thus an important ecological and economic trait. CRABS CLAW (CRC), a YABBY protein and putative transcription factor, is one of the major carpel developmental regulators in A. thaliana that includes a C2C2 zinc finger and a domain with similarities to an HMG box. CRC is involved in the regulation of processes such as carpel fusion and growth, floral meristem termination, and nectary formation. While its genetic interactions with other carpel development regulators are well described, its biochemical properties and molecular way of action remain unclear. We combined Bimolecular Fluorescence Complementation, Yeast Two-Hybrid, and Yeast One-Hybrid analyzes to shed light on the molecular biology of CRC. Our results showed that CRC dimerizes, also with other YABBY proteins, via the YABBY domain, and that its DNA binding is mainly cooperative and is mediated by the YABBY domain. Further, we identified that CRC is involved in floral meristem termination via transcriptional repression while it acts as a transcriptional activator in nectary development and carpel fusion and growth control. This work increases our understanding on how YABBY transcription factors interact with other proteins and how they regulate their targets.

Seed formation is a pivotal process in plant reproduction and dispersal. It begins with megagametophyte development in the ovule, followed by fertilization and subsequently coordinated development of embryo, endosperm, and maternal seed coat. Two closely related MADS-box genes, SHATTERPROOF 1 and 2 (SHP1 and SHP2) are involved in specifying ovule integument identity in Arabidopsis thaliana. The MADS box gene ARABIDOPSIS BSISTER (ABS or TT16) is required, together with SEEDSTICK (STK) for the formation of endothelium, part of the seed coat and innermost tissue layer formed by the maternal plant. Little is known about the genetic interaction of SHP1 and SHP2 with ABS and the coordination of endosperm and seed coat development. In this work, mutant and expression analysis shed light on this aspect of concerted development. Triple tt16 shp1 shp2 mutants produce malformed seedlings, seed coat formation defects, fewer seeds, and mucilage reduction. While shp1 shp2 mutants fail to coordinate the timely development of ovules, tt16 mutants show less peripheral endosperm after fertilization. Failure in coordinated division of the innermost integument layer in early ovule stages leads to inner seed coat defects in tt16 and tt16 shp1 shp2 triple mutant seeds. An antagonistic action of ABS and SHP1/SHP2 is observed in inner seed coat layer formation. Expression analysis also indicates that ABS represses SHP1, SHP2, and FRUITFUL expression. Our work shows that the evolutionary conserved Bsister genes are required not only for endothelium but also for endosperm development and genetically interact with SHP1 and SHP2 in a partially antagonistic manner.

Epigenetic marks like methylation of cytosines at CpG dinucleotides are essential for mammalian development and play a major role in the regulation of gene expression and chromatin architecture. The methyl-cytosine binding domain (MBD) protein family recognizes and translates this methylation mark. We have recently shown that the level of MeCP2 and MBD2, two members of the MBD family, increased during differentiation and their ectopic expression induced heterochromatin clustering in vivo. As oligomerization of these MBD proteins could constitute a factor contributing to the chromatin clustering effect, we addressed potential associations among the MBD family performing a series of different interaction assays in vitro as well as in vivo. Using recombinant purified MBDs we found that MeCP2 and MBD2 showed the stronger self and cross association as compared to the other family members. Besides demonstrating that these homo- and hetero-interactions occur in the absence of DNA, we could confirm them in mammalian cells using co-immunoprecipitation analysis. Employing a modified form of the fluorescent two-hybrid protein-protein interaction assay, we could clearly visualize these associations in single cells in vivo. Deletion analysis indicated that the region of MeCP2 comprising amino acids 163-309 as well the first 152 amino acids of MBD2 are the domains responsible for MeCP2 and MBD2 associations. Our results strengthen the possibility that MeCP2 and MBD2 direct interactions could crosslink chromatin fibers and therefore give novel insight into the molecular mechanism of MBD mediated global heterochromatin architecture.

B(sister) genes have been identified as the closest relatives of class B floral homeotic genes. Previous studies have shown that B(sister) genes from eudicots are involved in cell differentiation during ovule and seed development. However, the complete function of B(sister) genes in eudicots is masked by redundancy with other genes and little is known about the function of B(sister) genes in monocots, and about the evolution of B(sister) gene functions. Here we characterize OsMADS29, one of three MADS-box B(sister) genes in rice. Our analyses show that OsMADS29 is expressed in female reproductive organs including the ovule, ovule vasculature, and the whole seed except for the outer layer cells of the pericarp. Knock-down of OsMADS29 by double-stranded RNA-mediated interference (RNAi) results in shriveled and/or aborted seeds. Histological analyses of the abnormal seeds at 7 days after pollination (DAP) indicate that the symplastic continuity, including the ovular vascular trace and the nucellar projection, which is the nutrient source for the filial tissue at early development stages, is affected. Moreover, degeneration of all the maternal tissues in the transgenic seeds, including the pericarp, ovular vascular trace, integuments, nucellar epidermis and nucellar projection, is blocked as compared to control plants. Our results suggest that OsMADS29 has important functions in seed development of rice by regulating cell degeneration of maternal tissues. Our findings provide important insights into the ancestral function of B(sister) genes.

Methyl CpG binding protein 2 (MeCP2) binds DNA, and has a preference for methylated CpGs and, hence, in cells, it accumulates in heterochromatin. Even though it is expressed ubiquitously MeCP2 is particularly important during neuronal maturation. This is underscored by the fact that in Rett syndrome, a neurological disease, 80% of patients carry a mutation in the MECP2 gene. Since the MECP2 gene lies on the X chromosome and is subjected to X chromosome inactivation, affected patients are usually chimeric for wild type and mutant MeCP2. Here, we present the generation and characterization of the first rat monoclonal MeCP2 specific antibodies as well as mouse monoclonal antibodies and a rabbit polyclonal antibody. We demonstrate that our antibodies are suitable for immunoblotting, (chromatin) immunoprecipitation and immunofluorescence of endogenous and ectopically expressed MeCP2. Epitope mapping revealed that most of the MeCP2 monoclonal antibodies recognize the C-terminal domain and one the N-terminal domain of MeCP2. Using slot blot analysis, we determined a high sensitivity of all antibodies, detecting amounts as low as 1 ng of MeCP2 protein. Moreover, the antibodies recognize MeCP2 from different species, including human, mouse, rat and pig. Lastly, we have validated their use by analyzing and quantifying X chromosome inactivation skewing using brain tissue of MeCP2 heterozygous null female mice. The new MeCP2 specific monoclonal antibodies described here perform well in a large variety of immunological applications making them a very valuable set of tools for studies of MeCP2 pathophysiology in situ and in vitro.