MpFEW RHIZOIDS1 miRNA-mediated lateral inhibition controls rhizoid cell patterning in Marchantia polymorpha

Lateral inhibition patterns differentiated cell types among equivalent cells during development in bacteria, metazoans, and plants. Tip-growing rhizoid cells develop among flat epidermal cells in the epidermis of the early-diverging land plant Marchantia polymorpha. We show that the majority of rhizoid cells develop individually, but some develop in linear, one-dimensional groups (chains) of between 2 and 7 rhizoid cells in wild-type plants. The distribution of rhizoid cells can be accounted for within a simple cellular automata model of lateral inhibition. The model predicted that in the absence of lateral inhibition, two-dimensional rhizoid cell groups (clusters) form. These can be larger than those formed with lateral inhibition. M. polymorpha rhizoid differentiation is positively regulated by the ROOT HAIR DEFECTIVE SIX-LIKE1 (MpRSL1) basic-helix-loop-helix (bHLH) transcription factor, which is directly repressed by the FEW RHIZOIDS1 (MpFRH1) microRNA (miRNA). To test if MpFRH1 miRNA acts during lateral inhibition, we generated loss-of-function (lof) mutants without the MpFRH1 miRNA. Two-dimensional clusters of rhizoids develop in Mpfrh1lof mutants as predicted by the model for plants that lack lateral inhibition. Furthermore, two-dimensional clusters of up to 9 rhizoid cells developed in the Mpfrh1lof mutants compared to a maximum number of 7 observed in wild-type groups. The higher steady-state levels of MpRSL1 mRNA in Mpfrh1lof mutants indicate that MpFRH1-mediated lateral inhibition involves the repression of MpRSL1 activity. Together, the modeling and genetic data indicate that MpFRH1 miRNA mediates lateral inhibition by repressing MpRSL1 during pattern formation in the M. polymorpha epidermis

A Transcriptome Atlas of Physcomitrella patens Provides Insights into the Evolution and Development of Land Plants

Post-print version of the article.Identifying the genetic mechanisms that underpin the evolution of new organ and tissue systems is an aim of evolutionary developmental biology. Comparative functional genetic studies between angiosperms and bryophytes can define those genetic changes that were responsible for developmental innovations. Here, we report the generation of a transcriptome atlas covering most phases in the life cycle of the model bryophyte Physcomitrella patens, including detailed sporophyte developmental progression. We identified a comprehensive set of sporophyte-specific transcription factors, and found that many of these genes have homologs in angiosperms that function in developmental processes such as flowering and shoot branching. Deletion of the PpTCP5 transcription factor results in development of supernumerary sporangia attached to a single seta, suggesting that it negatively regulates branching in the moss sporophyte. Given that TCP genes repress branching in angiosperms, we suggest that this activity is ancient. Finally, comparison of P. patens and Arabidopsis thaliana transcriptomes led us to the identification of a conserved core of transcription factors expressed in tip-growing cells. We identified modifications in the expression patterns of these genes that could account for developmental differences between P. patens tip-growing cells and A. thaliana pollen tubes and root hairs.ERA-NET: (2nd call ERA-NET for Coordinating Plant Sciences); Fundação para a Ciência e a Tecnologia

The coannihilation codex

We present a general classification of simplified models that lead to dark matter (DM) coannihilation processes of the form DM + X → SM1 + SM2, where X is a coannihilation partner for the DM particle and SM1, SM2 are Standard Model fields. Our classification also encompasses regular DM pair annihilation scenarios if DM and X are identical. Each coannhilation scenario motivates the introduction of a mediating particle M that can either belong to the Standard Model or be a new field, whereby the resulting interactions between the dark sector and the Standard Model are realized as tree-level and dimension-four couplings. We construct a basis of coannihilation models, classified by the SU(3)C x SU(2)L x U(1)Y quantum numbers of DM, X and M. Our main assumptions are that dark matter is an electrically neutral color singlet and that all new particles are either scalars, Dirac or Majorana fermions, or vectors. We illustrate how new scenarios arising from electroweak symmetry breaking e ects can be connected to our electroweak symmetric simplified models. We o er a comprehensive discussion of the phenomenological features of our models, encompassing the physics of thermal freeze-out, direct and indirect detection constraints, and in particular searches at the Large Hadron Collider (LHC). Many novel signatures that are not covered in current LHC searches are emphasized, and new and improved LHC analyses tackling these signatures are proposed. We discuss how the coannihilation simplified models can be used to connect results from all classes of experiments in a straightforward and transparent way. This point is illustrated with a detailed discussion of the phenomenology of a particular simplified model featuring leptoquark-mediated dark matter coannihilation

Framework and baseline examination of the German National Cohort (NAKO)

The German National Cohort (NAKO) is a multidisciplinary, population-based prospective cohort study that aims to investigate the causes of widespread diseases, identify risk factors and improve early detection and prevention of disease. Specifically, NAKO is designed to identify novel and better characterize established risk and protection factors for the development of cardiovascular diseases, cancer, diabetes, neurodegenerative and psychiatric diseases, musculoskeletal diseases, respiratory and infectious diseases in a random sample of the general population. Between 2014 and 2019, a total of 205,415 men and women aged 19–74 years were recruited and examined in 18 study centres in Germany. The baseline assessment included a face-to-face interview, self-administered questionnaires and a wide range of biomedical examinations. Biomaterials were collected from all participants including serum, EDTA plasma, buffy coats, RNA and erythrocytes, urine, saliva, nasal swabs and stool. In 56,971 participants, an intensified examination programme was implemented. Whole-body 3T magnetic resonance imaging was performed in 30,861 participants on dedicated scanners. NAKO collects follow-up information on incident diseases through a combination of active follow-up using self-report via written questionnaires at 2–3 year intervals and passive follow-up via record linkages. All study participants are invited for re-examinations at the study centres in 4–5 year intervals. Thereby, longitudinal information on changes in risk factor profiles and in vascular, cardiac, metabolic, neurocognitive, pulmonary and sensory function is collected. NAKO is a major resource for population-based epidemiology to identify new and tailored strategies for early detection, prediction, prevention and treatment of major diseases for the next 30 years. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10654-022-00890-5

Report from Working Group 3: Beyond the standard model physics at the HL-LHC and HE-LHC

This is the third out of five chapters of the final report [1] of the Workshop on Physics at HL-LHC, and perspectives on HE-LHC [2]. It is devoted to the study of the potential, in the search for Beyond the Standard Model (BSM) physics, of the High Luminosity (HL) phase of the LHC, defined as $3$ ab$^{-1}$ of data taken at a centre-of-mass energy of 14 TeV, and of a possible future upgrade, the High Energy (HE) LHC, defined as $15$ ab$^{-1}$ of data at a centre-of-mass energy of 27 TeV. We consider a large variety of new physics models, both in a simplified model fashion and in a more model-dependent one. A long list of contributions from the theory and experimental (ATLAS, CMS, LHCb) communities have been collected and merged together to give a complete, wide, and consistent view of future prospects for BSM physics at the considered colliders. On top of the usual standard candles, such as supersymmetric simplified models and resonances, considered for the evaluation of future collider potentials, this report contains results on dark matter and dark sectors, long lived particles, leptoquarks, sterile neutrinos, axion-like particles, heavy scalars, vector-like quarks, and more. Particular attention is placed, especially in the study of the HL-LHC prospects, to the detector upgrades, the assessment of the future systematic uncertainties, and new experimental techniques. The general conclusion is that the HL-LHC, on top of allowing to extend the present LHC mass and coupling reach by $20-50\%$ on most new physics scenarios, will also be able to constrain, and potentially discover, new physics that is presently unconstrained. Moreover, compared to the HL-LHC, the reach in most observables will, generally more than double at the HE-LHC, which may represent a good candidate future facility for a final test of TeV-scale new physics

The microRNA FEW RHIZOIDS1 controls rhizoid patterning in the liverwort Marchantia polymorpha

MicroRNAs (miRNAs) control gene expression and consequently play regulatory roles in the development of plants and animals. The FEW RHIZODS 1 (MpFRH1) miRNA of the liverwort Marchantia polymorpha was identified as a negative regulator of rhizoid development. ROOT HAIR DEFECTIVE 6-LIKE (RSL) class I basic Helix-Loop-Helix transcription factors (TFs) positively regulate rhizoid development in bryophytes and root hair development in angiosperms, thus being conserved positive regulators of tip-growing cells with a rooting function in land plants. Here, I demonstrate that MpFRH1 directly targets the MpRSL1 mRNA, the only RSL class I TF in M. polymorpha. While GLABRA2 (AtGL2) negatively regulates RSL class I TF expression in the angiosperm Arabidopsis thaliana, the function of MpFRH1 as a negative regulator of RSL class I TFs in liverworts demonstrates that independent mechanisms evolved to repress RSL class I TF expression in different land plant lineages. To determine how MpFRH1 represses rhizoid development I generated loss of function (LOF) mutations in the MpFRH1 gene. I showed that rhizoid initials develop larger clusters in Mpfrh1LOF plants than in wildtype. Furthermore, the lack of MpFRH1 activity causes the development of supernumerary mucilage papillae cells and meristematic notches. These findings indicate that MpFRH1 suppresses the development of ectopic epidermal structures such as rhizoid cells and mucilage papillae cells as well as apical cells in meristems. By combining functional and spatiotemporal expression data of both MpFRH1 and MpRSL1, using promoter reporter constructs, an MpFRH1 activity biosensor and in situ hybridizations, I suggest that MpFRH1 may act as a mobile miRNA required for lateral inhibition during epidermal patterning formation.</p

Cytomegalovirus (CMV) seroprevalence in the adult population of Germany

Background: Infection with cytomegalovirus (CMV) remains asymptomatic in most immunocompetent hosts, but is the leading cause of congenital viral infection worldwide and can be life-threatening in immunocompromised individuals. We aimed to assess CMV seroprevalence in a nationally representative sample of adults in Germany and to identify sociodemographic factors associated with CMV seropositivity. Methods: Blood samples from 6552 participants (18–79 years) of the “German National Health Interview and Examination Survey 1998”, a population-based sample of the adult population in Germany, were tested for the presence of CMV antibodies using an Ig-multiplex assay. Weighted seroprevalence was calculated and weighted binomial regression was used to identify factors associated with CMV seropositivity. Results: Overall CMV seroprevalence was 56.7% (95%CI: 54.8–58.7%), with a higher seroprevalence in women (62.3%) than in men (51.0%). Seroprevalence increased with age: from 31.8% to 63.7% in men and from 44.1% to 77.6% in women when comparing the 18–29 with the 70–79 year age-group, respectively. CMV seroprevalence in women of childbearing age (18–45 years) was 51.7%. Factors significantly associated with CMV seropositivity were age, country of birth, smoking status, education, living in northern Germany and number of household members. In addition, having attended child care was associated with seropositivity in men, and number of siblings and living in East Germany in women. Conclusion: Our results indicate that half the women of childbearing age were susceptible for primary CMV infection during pregnancy. CMV screening during pregnancy and informing seronegative women about CMV risk reduction measures could prevent congenital CMV infections with its serious consequences.Peer Reviewe