HvSL1 and HvMADS16 promote stamen identity to restrict multiple ovary formation in barley

Correct floral development is the result of a sophisticated balance of molecular cues. Floral mutants provide insight into the main genetic determinants that integrate these cues, as well as providing opportunities to assess functional variation across species. In this study, we characterize the barley (Hordeum vulgare) multiovary mutants mov2.g and mov1, and propose causative gene sequences: a C2H2 zinc-finger gene HvSL1 and a B-class gene HvMADS16, respectively. In the absence of HvSL1, florets lack stamens but exhibit functional supernumerary carpels, resulting in multiple grains per floret. Deletion of HvMADS16 in mov1 causes homeotic conversion of lodicules and stamens into bract-like organs and carpels that contain non-functional ovules. Based on developmental, genetic, and molecular data, we propose a model by which stamen specification in barley is defined by HvSL1 acting upstream of HvMADS16. The present work identifies strong conservation of stamen formation pathways with other cereals, but also reveals intriguing species-specific differences. The findings lay the foundation for a better understanding of floral architecture in Triticeae, a key target for crop improvement.

Satisfaction and experience with colorectal cancer screening: a systematic review of validated patient reported outcome measures

BACKGROUND

Patient satisfaction or experience with colorectal cancer screening can determine adherence to screening programs. An evaluation of validated patient reported outcome measures (PROMs) for measuring experience or satisfaction with colorectal cancer screening does not exist. Our objective was to identify and critically appraise validated questionnaires for measuring patient satisfaction or experience with colorectal cancer screening.

METHODS

We conducted a systematic review following the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) methodology. We conducted searches on MEDLINE, EMBASE, PsychINFO, CINAHL and BiblioPRO and assessed the methodological quality of studies and measurement properties of questionnaires according to the COSMIN guidelines for systematic reviews of PROMs. PROSPERO registration number: CRD42019118527.

RESULTS

We included 80 studies that used 75 questionnaires, of which only 5 were validated. Four questionnaires measured satisfaction with endoscopy: two in the context of colorectal cancer screening (for colonoscopy and sigmoidoscopy) and two for non-screening endoscopy. One questionnaire measured satisfaction with bowel preparation. The methodological quality of studies was variable. The questionnaires with evidence for sufficient content validity and internal consistency were: the CSSQP questionnaire, which measures safety and satisfaction with screening colonoscopy, and the Post-Procedure questionnaire which measures satisfaction with non-screening endoscopic procedures.

CONCLUSIONS

This systematic review shows that a minority of existing PROMs for measuring patient satisfaction with colorectal cancer screening are validated. We identified two questionnaires with high potential for further use (CSSQP and the Post-Procedure questionnaire).

HvLEAFY controls the early stages of floral organ specification and inhibits the formation of multiple ovaries in barley

Transition to the reproductive phase, inflorescence formation and flower development are crucial elements that ensure maximum reproductive success in a plant's life cycle. To understand the regulatory mechanisms underlying correct flower development in barley (Hordeum vulgare), we characterized the multiovary 5 (mov5.o) mutant. This mutant develops abnormal flowers that exhibit mosaic floral organs typified by multiple carpels at the total or partial expense of stamens. Genetic mapping positioned mov5 on the long arm of chromosome 2H, incorporating a region that encodes HvLFY, the barley orthologue of LEAFY from Arabidopsis. Sequencing revealed that, in mov5.o plants, HvLFY contains a single amino acid substitution in a highly conserved proline residue. CRISPR-mediated knockout of HvLFY replicated the mov5.o phenotype, suggesting that HvLFY_mov5 represents a loss of function allele. In heterologous assays, the HvLFY_mov5 polymorphism influenced protein-protein interactions and affinity for a putative binding site in the promoter of HvMADS58, a C-class MADS-box gene. Moreover, molecular analysis indicated that HvLFY interacts with HvUFO and regulates the expression of floral homeotic genes including HvMADS2, HvMADS4 and HvMADS16. Other distinct changes in expression differ from those reported in the rice LFY mutants apo2/rfl, suggesting that LFY function in the grasses is modulated in a species-specific manner. This pathway provides a key entry point for the study of LFY function and multiple ovary formation in barley, as well as cereal species in general.

Hybrid breeding in wheat: how shaping floral biology can offer new perspectives

Hybrid breeding in wheat (Triticum aestivum L.) has the potential to deliver major yield increases. This is a requisite to guarantee food security for increasing population demands and to counterbalance the effects of extreme environmental conditions. Successful hybrid breeding in wheat relies on forced outcrossing while preventing self-pollination. To achieve this, research has been directed towards identifying and improving fertility control systems. To maximise cross-pollination and seed set, however, fertility control systems need to be complemented by breeding phenotypically distinct male and female lines. This review summarises existing and novel male sterility systems for wheat hybridisation. We also consider the genetic resources that can be used to alter wheat's floral development and spike morphology, with a focus on the genetic variation already available. Exploiting these resources can lead to enhanced outcrossing, a key requirement in the progress towards hybrid wheat breeding.

Uncovering the evolutionary origin of blue anthocyanins in cereal grains

Functional divergence after gene duplication plays a central role in plant evolution. Among cereals, only Hordeum vulgare (barley), Triticum aestivum (wheat) and Secale cereale (rye) accumulate delphinidin-derived (blue) anthocyanins in the aleurone layer of grains, whereas Oryza sativa (rice), Zea mays (maize) and Sorghum bicolor (sorghum) do not. The underlying genetic basis for this natural occurrence remains elusive. Here, we mapped the barley Blx1 locus involved in blue aleurone to an approximately 1.13 Mb genetic interval on chromosome 4HL, thus identifying a trigenic cluster named MbHF35 (containing HvMYB4H, HvMYC4H and HvF35H). Sequence and expression data supported the role of these genes in conferring blue-coloured (blue aleurone) grains. Synteny analyses across monocot species showed that MbHF35 has only evolved within distinct Triticeae lineages, as a result of dispersed gene duplication. Phylogeny analyses revealed a shared evolution pattern for MbHF35 in Triticeae, suggesting that these genes have co-evolved together. We also identified a Pooideae-specific flavonoid 3',5'-hydroxylase (F3'5'H) lineage, termed here Mo_F35H2, which has a higher amino acid similarity with eudicot F3'5'Hs, demonstrating a scenario of convergent evolution. Indeed, selection tests identified 13 amino acid residues in Mo_F35H2 that underwent positive selection, possibly driven by protein thermostablility selection. Furthermore, through the interrogation of barley germplasm there is evidence that HvMYB4H and HvMYC4H have undergone human selection. Collectively, our study favours blue aleurone as a recently evolved trait resulting from environmental adaptation. Our findings provide an evolutionary explanation for the absence of blue anthocyanins in other cereals and highlight the importance of gene functional divergence for plant diversity and environmental adaptation.

Colorectal cancer guidelines seldom include the patient perspective

OBJECTIVES

This study aimed to describe how colorectal practice guidelines (PGs) incorporate the patient perspective.

STUDY DESIGN AND SETTING

We searched in the Guidelines International Network library, MEDLINE, National Guideline Clearinghouse, NHS Evidence database, and TRIP database. Two authors independently selected the PGs. We considered recommendations rated or worded as weak or conditional or suggesting multiple options, as potentially preference sensitive. Two authors independently evaluated if, in potentially sensitive recommendations, the patient perspective was incorporated.

RESULTS

We included 28 PGs that contained 588 recommendations, being 256 potentially preference sensitive. Ten PGs (36%) included patients in the development process, and 12 (43%) provided information about patients' perspectives. Nine PGs (32%) included recommendations in which the patient perspective was explicitly considered, and 13 (46.4%) that recommended a discussion with the patient. From a total of 588 recommendations, 9.7% (25/256) of potentially preference-sensitive recommendations considered the patient perspective. The inclusion of patients in the development process was associated with a more frequent incorporation of the patient perspective in potentially preference sensitive recommendations (70% vs. 0%; P < 0.001).

CONCLUSIONS

Guideline users should be aware that the incorporation of the patient perspective in colorectal cancer PGs is suboptimal. Guideline developers should make efforts to incorporate the patient perspective, especially in preference-sensitive recommendations.

Gene coexpression patterns during early development of the native Arabidopsis reproductive meristem: novel candidate developmental regulators and patterns of functional redundancy

During very early stages of flower development in Arabidopsis thaliana, a series of key decisions are taken. Indeed, the position and the basic patterning of new flowers are determined in less than 4 days. Given that the scientific literature provides hard evidence for the function of only 10% of A. thaliana genes, we hypothesized that although many essential genes have already been identified, many poorly characterized genes are likely to be involved in floral patterning. In the current study, we use high-throughput sequencing to describe the transcriptome of the native inflorescence meristem, the floral meristem and the new flower immediately after the start of organ differentiation. We provide evidence that our experimental system is reliable and less affected by experimental artefacts than a widely used floral induction system. Furthermore, we show how these data can be used to identify candidate genes for functional studies, and to generate hypotheses of functional redundancies and regulatory interactions.

Gammadelta T cell activation by chronic HIV infection may contribute to intrahepatic vdelta1 compartmentalization and hepatitis C virus disease progression independent of highly active antiretroviral therapy

HIV and hepatis C virus (HCV) coinfection is frequently associated with rapid progression of HCV-related disease, resulting in a higher risk of cirrhosis. Data suggest that natural T cells expressing the Vdelta1 T cell receptor rearrangement are recruited in the liver of chronically HCV-infected patients and are increased in the peripheral blood of HIV-infected persons. We studied gammadelta T cell distribution in the peripheral blood and liver of HCV-infected and HIV/HCV-coinfected patients in the presence and absence of antiretroviral therapy. We observed that Vdelta1+ T cells releasing helper T cell type 1 cytokines are compartmentalized not only in the liver of HCV+ patients, but also of HIV/HCV-coinfected persons. HIV/HCV patients showed an increased frequency of both peripheral and intrahepatic Vdelta1 natural T lymphocytes, resulting in a higher degree of hepatic inflammation when compared with patients with other liver diseases. Finally, highly active antiretroviral therapy (HAART) was unable to restore Vdelta1T cell circulation to normal levels in chronically HIV-infected persons. We conclude that gammadelta T lymphocytes released from tissue to the bloodstream circulation under the influence of chronic HIV infection may contribute to intrahepatic Vdelta1 compartmentalization and progression of liver disease, independently of HAART.

Characterization of [3H]CGP 12177 binding to beta-adrenergic receptors in intact eel hepatocytes

The aim of this study was to characterize [3H]CGP 12177 (CGP) binding to beta-adrenergic receptors in isolated hepatocytes of the European eel (Anguilla anguilla), in which the involvement of cAMP in epinephrine-induced glucose release has been previously observed. Specific binding of CGP was saturable, reversible, and linear as a function of cell number. Analysis of binding data suggested a single class of binding sites, with a Kd of 1.31 nM and a number of approximately 7000 beta-adrenergic receptors per cell. The potency order of specific inhibition of [3H]CGP binding was CGP > propranolol > or = alprenolol >> butoxamine > or = atenolol, while phentolamine and prazosin failed to significantly displace the tracer at concentrations up to 100 microM. The binding kinetics of CGP were closely related to its biological effect. In fact, the drug dose-dependently counteracted the enhancement of intracellular cAMP levels induced by epinephrine in isolated hepatocytes with a Kd of 1.06 nM. Moreover, it antagonized the hormone-induced stimulation of adenylyl cyclase activity in hepatic membranes as well as of glucose release from cells. These data clearly show that beta-adrenergic receptors are coupled to the adenylyl cyclase/cAMP transduction pathway in eel liver.