The G(1) cyclin Cln3 promotes cell cycle entry via the transcription factor Swi6

In Saccharomyces cerevisiae (budding yeast), commitment to cell division in late G1 is promoted by the G1 cyclin Cln3 and its associated cyclin-dependent kinase, Cdc28. We show here that all known aspects of the function of Cln3 in G1 phase, including control of cell size, pheromone sensitivity, cell cycle progress, and transcription, require the protein Swi6. Swi6 is a component of two related transcription factors, SBF and MBF, which are known to regulate many genes at the G1-S transition. The Cln3-Cdc28 complex somehow activates SBF and MBF, but there was no evidence for direct phosphorylation of SBF/MBF by Cln3-Cdc28 or for a stable complex between SBF/MBF and Cln3-Cdc28. The activation also does not depend on the ability of Cln3 to activate transcription when artificially recruited directly to a promoter. The amino terminus and the leucine zipper of Swi6 are important for the ability of Swi6 to respond to Cln3 but are not essential for the basal transcriptional activity of Swi6. Cln3-Cdc28 may activate SBF and MBF indirectly, perhaps by phosphorylating some intermediary protein

Centralization of pediatric surgical care in the Netherlands:Lessons learned

Centralization of care is a difficult process, as there are several stakeholders that are involved and should be heard. What can be the best option for a small group of patients may be detrimental to a larger group of patients that cannot be adequately treated close to home. The weighing of these factors is different in every environment. One universal rule however is: if you don't do it yourselves, others will do it for you. In the Netherlands, pediatric oncology, including surgery, is centralized in one center (Utrecht) with the help of several shared care centers scattered throughout the country for things that can be managed close to home. (c) 2021 Elsevier Inc. All rights reserved

HOXA10 controls osteoblastogenesis by directly activating bone regulatory and phenotypic genes

HOXA10 is necessary for embryonic patterning of skeletal elements, but its function in bone formation beyond this early developmental stage is unknown. Here we show that HOXA10 contributes to osteogenic lineage determination through activation of Runx2 and directly regulates osteoblastic phenotypic genes. In response to bone morphogenic protein BMP2, Hoxa10 is rapidly induced and functions to activate the Runx2 transcription factor essential for bone formation. A functional element with the Hox core motif was characterized for the bone-related Runx2 P1 promoter. HOXA10 also activates other osteogenic genes, including the alkaline phosphatase, osteocalcin, and bone sialoprotein genes, and temporally associates with these target gene promoters during stages of osteoblast differentiation prior to the recruitment of RUNX2. Exogenous expression and small interfering RNA knockdown studies establish that HOXA10 mediates chromatin hyperacetylation and trimethyl histone K4 (H3K4) methylation of these genes, correlating to active transcription. HOXA10 therefore contributes to early expression of osteogenic genes through chromatin remodeling. Importantly, HOXA10 can induce osteoblast genes in Runx2 null cells, providing evidence for a direct role in mediating osteoblast differentiation independent of RUNX2. We propose that HOXA10 activates RUNX2 in mesenchymal cells, contributing to the onset of osteogenesis, and that HOXA10 subsequently supports bone formation by direct regulation of osteoblast phenotypic genes. <br/

Use of genome-scale metabolic models for plant metabolism

Genome-scale metabolic models (GSMM) have been extensively applied for a wide variety of organisms. However, for plants genome-scale modeling is still in its infancy. It has been successfully developed for Arabidopsis in the last few years. In this study we appraise the existing GSMM for Arabidopsis by computing biomass accumulation using flux balance analysis (FBA) and attempt to outline potential applications for horticultural crops in the future. The predicted growth rates for the Poolman et al. (2009) and Dal’Molin et al. (2010) model were quite similar, despite different carbon sources were provided (glucose and sucrose,100 mmol/g*h DW). The exchange fluxes for respiration in nonphotosynthetic cells confirmed that plants prefer NH3 in the process of nitrogen assimilation. When carbohydrates were used as substrate for respiration the Respiratory quotient (RQ) of Poolman’s model approached 1, which is consistent with experimental data. For the Dal’Molin’s model the RQ is less than 1. H2S is utilized in the Dal’Molin model as sulfur source, whereas sulfate (SO42-) is consumed in the Poolman’s model. The Poolman’s model seems to reflect biological reality more closely than the Dal’Molin model. This could be due to the subcellular compartmentation included in the Dal’Molin model, adding subcellular compartmentation of reactions was done manually. In conclusion, to apply constraints-based reconstruction and analysis (COBRA) methods, including FBA, to plant metabolism requires careful analysis and possibly curation of existing GSMM’s

Nuclear structure-gene expression interrelationships: implications for aberrant gene expression in cancer

There is long-standing recognition that transformed and tumor cells exhibit striking alterations in nuclear morphology as well as in the representation and intranuclear distribution of nucleic acids and regulatory factors. Parameters of nuclear structure support cell growth and phenotypic properties of cells by facilitating the organization of genes, replication and transcription sites, chromatin remodeling complexes, transcripts, and regulatory factors in structurally and functionally definable subnuclear domains within the three-dimensional context of nuclear architecture. The emerging evidence for functional interrelationships of nuclear structure and gene expression is consistent with linkage of tumor-related modifications in nuclear organization to compromised gene regulation during the onset and progression of cancer

Urological anomalies in anorectal malformations in the Netherlands: Effects of screening all patients on long-term outcome

Introduction: Urological anomalies are frequently seen in patients with anorectal malformations (ARM) and can result in upper urinary tract deterioration. Whether the current method of screening is valid, adequate and needed for all patients is not clear. We, therefore, evaluated the urological screening methods in our ARM patients for changes in urological treatment, outcome and follow-up. Methods: The medical records of 331 children born with an ARM in the period 1983-2003 were retrospectively studied. Documentation of diagnosis, screening method, urological anomalies, treatment, complications, follow-up and outcome were measured. Results: The overall incidence of urological anomalies was 52%. The incidence of urological anomalies and urological follow-up time decreased with diminishing complexity of the ARM. Hydronephrosis, vesico-urethral reflux, lower urinary tract dysfunction and urinary incontinence were encountered most. Treatment invasiveness increased with the increase of complexity of an ARM. Lower urinary tract dysfunction needing urological care occurred in 43% in combination with lumbosacral or spinal cord anomalies and in 8% with no abnormalities in the lumbosacral-/spinal region. Conclusions: Urological anomalies in patients with complex ARM are more severe than in patients with less complex ARM. Ultrasonography of the urinary tract should be performed in all patients. Voiding cysto-urethrography can be reserved for patients with dilated upper urinary tracts, urinary tract infections or lumbosacral and spinal abnormalities. All patients with complex ARM need urodynamic investigations. When using these indications, the screening for urological anomalies in ARM patients can be optimized with long-term follow-up in selected patients

Diagnostic accuracy of evaluation of suspected syncope in the emergency department:usual practice vs. ESC guidelines

Background: Syncope is a frequent reason for referral to the emergency department. After excluding a potentially life-threatening condition, the second objective is to find the cause of syncope. The objective of this study was to assess the diagnostic accuracy of the treating physician in usual practice and to compare this to the diagnostic accuracy of a standardised evaluation, consisting of thorough history taking and physical examination by a research physician. Methods: This prospective cohort study included suspected (pre) syncope patients without an identified serious underlying condition who were assessed in the emergency department. Patients were initially seen by the initial treating physician and the usual evaluation was performed. A research physician, blinded to the findings of the initial treating physician, then performed a standardised evaluation according to the ESC syncope guidelines. Diagnostic accuracy (proportion of correct diagnoses) was determined by expert consensus after long-term follow-up. Results: One hundred and one suspected (pre) syncope patients were included (mean age 59 ± 20 years). The usual practice of the initial treating physicians did not in most cases follow ESC syncope guidelines, with orthostatic blood pressure measurements made in only 40% of the patients. Diagnostic accuracy by the initial treating physicians was 65% (95% CI 56-74%), while standardised evaluation resulted in a diagnostic accuracy of 80% (95% CI 71-87%; p = 0.009). No life-threatening causes were missed. Conclusions: Usual practice of the initial treating physician resulted in a diagnostic accuracy of 65%, while standardised practice, with an emphasis on thorough history taking, increased diagnostic accuracy to 80%. Results suggest that the availability of additional resources does not result in a higher diagnostic accuracy than standardised evaluation, and that history taking is the most important diagnostic test in suspected syncope patients. Netherlands Trial Registration: NTR5651. Registered 29 January 2016, https://www.trialregister.nl/trial/553