p53Psi is a transcriptionally inactive p53 isoform able to reprogram cells toward a metastatic-like state

Although much is known about the underlying mechanisms of p53 activity and regulation, the factors that influence the diversity and duration of p53 responses are not well understood. Here we describe a unique mode of p53 regulation involving alternative splicing of the TP53 gene. We found that the use of an alternative 3' splice site in intron 6 generates a unique p53 isoform, dubbed p53Psi. At the molecular level, p53Psi is unable to bind to DNA and does not transactivate canonical p53 target genes. However, like certain p53 gain-of-function mutants, p53Psi attenuates the expression of E-cadherin, induces expression of markers of the epithelial-mesenchymal transition, and enhances the motility and invasive capacity of cells through a unique mechanism involving the regulation of cyclophilin D activity, a component of the mitochondrial inner pore permeability. Hence, we propose that p53Psi encodes a separation-of-function isoform that, although lacking canonical p53 tumor suppressor/transcriptional activities, is able to induce a prometastatic program in a transcriptionally independent manner

Genetic variability, chemotype distribution, and aggressiveness of Fusarium culmorum on durum wheat in Tunisia

Fusarium culmorum is the most commonly reported root rot pathogen in Tunisian durum wheat. Isolates of the pathogen from four durum wheat growing areas in the north of Tunisia were analyzed for their chemotypes. Two chemotypes were detected at unequal abundance (96% of 3-ADON and 4% of NIV). Distribution of a SNP mutation located at the position 34 bp after the first exon of the EF-1\u3b1 partial sequence was analysed, to verify whether the haplotype was specifically associated to Fusarium root rot. A and T haplotypes were homogeneously distributed in three different Tunisian regions (Mateur, Beja and Bousalem) but not for the region of Bizerte, from which greatest number of A haplotype strains were detected. The isolates were tested for their virulence under glasshouse conditions, and a mean of 91% of crown and root infection was observed. Chemotype influenced virulence, but there was no significant influence of the geographical origin or haplotype on virulence. The distribution of three inter simple sequence repeats (ISSR) was examined, to better understand the structure of F. culmorum populations in Tunisia. A total of 27 fragments were obtained with eight polymorphic bands. Cluster analysis showed a high level of similarity between isolates. Analysis of molecular variance confirmed that there was little genetic differentiation among F. culmorum strains from different locations

Spatial Analyses of Mono, Di and Trinucleotide Trends in Plant Genes

Genomic DNA sequences display compositional heterogeneity on many scales. In this paper we analyzed tendencies and anomalies in the occurence of mono, di and trinucleotides in structural regions of plant genes. Representation of these trends as a function of position along genic sequences highlighted compositional features peculiar of either monocots or eudicots that were remarkably uniform within these two evolutionary clades. The most evident of these features appeared in the form of gradient of base content along the direction of transcription. The robustness of such a representation was validated in sequences sub-datasets generated considering structural and compositional features such as total length of cds, overall GC content and genic orientation in the genome. Piecewise regression analyses indicated that the gradients could be conveniently approximated to a two segmented model where a first region featuring a steep slope is followed by a second segment fitting a milder variation. In general, monocots species showed steeper segments than eudicots. The guanine gradient was the most distinctive feature between the two evolutionary clades, being moderately increasing in eudicots and firmly decreasing in monocots. Single gene investigation revealed that a high proportion of genes show compositional trends compatible with a segmented model suggesting that these features are essential attributes of gene organization. Dinucleotide and trinucleotide biases were referred to expectation based on a random union of the component elements. The average bias at dinucleotide level identified a significant undererpresentation of some dinucleotide and the overrepresention of others. The bias at trinucleotide level was on average low. Finally, the analysis of bryophyte coding sequences showed mononucleotide, dinucleotide and trinucleotide compositional trends resembling those of higher plants. This finding suggested that the emergenge of compositional bias is an ancient event in evolution which was already present at the time of land conquest by green plants

Human cytomegalovirus genomes sequenced directly from clinical material: variation, multiple-strain infection, recombination and gene loss

The genomic characteristics of human cytomegalovirus (HCMV) strains sequenced directly from clinical pathology samples were investigated, focusing on variation, multiple-strain infection, recombination, and gene loss. A total of 207 datasets generated in this and previous studies using target enrichment and high-throughput sequencing were analyzed, in the process enabling the determination of genome sequences for 91 strains. Key findings were that (i) it is important to monitor the quality of sequencing libraries in investigating variation; (ii) many recombinant strains have been transmitted during HCMV evolution, and some have apparently survived for thousands of years without further recombination; (iii) mutants with nonfunctional genes (pseudogenes) have been circulating and recombining for long periods and can cause congenital infection and resulting clinical sequelae; and (iv) intrahost variation in single-strain infections is much less than that in multiple-strain infections. Future population-based studies are likely to continue illuminating the evolution, epidemiology, and pathogenesis of HCMV

Nuclear Organization and Dynamics of 7SK RNA in Regulating Gene Expression

We have identified 7SK RNA to be enriched in nuclear speckles. Knock-down of 7SK results in the mislocalization of nuclear speckle constituents, and the transcriptional up-regulation of a reporter gene locus. 7SK RNA transiently associates with the locus upon transcriptional down-regulation correlating with the displacement of pTEF-b

Communication and visiting policies in Italian intensive care units during the first COVID-19 pandemic wave and lockdown: a nationwide survey

Background: During the first coronavirus disease 2019 (COVID-19) pandemic wave, an unprecedented number of patients with respiratory failure due to a new, highly contagious virus needed hospitalization and intensive care unit (ICU) admission. The aim of the present study was to describe the communication and visiting policies of Italian intensive care units (ICUs) during the first COVID-19 pandemic wave and national lockdown and compare these data with prepandemic conditions. Methods: A national web-based survey was conducted among 290 Italian hospitals. Each ICU (active between February 24 and May 31, 2020) was encouraged to complete an individual questionnaire inquiring the hospital/ICU structure/organization, communication/visiting habits and the role of clinical psychology prior to, and during the first COVID-19 pandemic wave. Results: Two hundred and nine ICUs from 154 hospitals (53% of the contacted hospitals) completed the survey (202 adult and 7 pediatric ICUs). Among adult ICUs, 60% were dedicated to COVID-19 patients, 21% were dedicated to patients without COVID-19 and 19% were dedicated to both categories (Mixed). A total of 11,102 adult patients were admitted to the participating ICUs during the study period and only approximately 6% of patients received at least one visit. Communication with family members was guaranteed daily through an increased use of electronic devices and was preferentially addressed to the same family member. Compared to the prepandemic period, clinical psychologists supported physicians more often regarding communication with family members. Fewer patients received at least one visit from family members in COVID and mixed-ICUs than in non-COVID ICUs, l (0 [0–6]%, 0 [0–4]% and 11 [2–25]%, respectively, p < 0.001). Habits of pediatric ICUs were less affected by the pandemic. Conclusions: Visiting policies of Italian ICUs dedicated to adult patients were markedly altered during the first COVID-19 wave. Remote communication was widely adopted as a surrogate for family meetings. New strategies to favor a family-centered approach during the current and future pandemics are warranted

Synthesis and prospective study of the use of thiophene thiosemicarbazones as signalling scaffolding for the recognition of anions

A family of phenyl-thiosemicarbazone dyes have been prepared and their interactions with anions monitorized via UV-Vis, fluorescence and 1H NMR titrations. Additionally quantum chemical calculations and electrochemical studies completed the studies carried out. The phenyl-thiosemicarbazone dyes show a modulation of their hydrogen-bonding and electron-donating capabilities as a function of the chemical groups attached and display two different chromo-fluorogenic responses towards anions in acetonitrile solutions. The more basic anions fluoride and cyanide are able to induce the dual coordination-deprotonation processes for all the receptors studied, whereas acetate only interacts with receptors 2, 3, 6, 7, 8, 9 and dihydrogen phosphate displays sensing features only with the more acidic receptors 6. Coordinative hydrogen bonding interactions is indicated by a small bathochromic shift, whilst deprotonation results in the appearance of a new band at ca. 400-450 nm corresponding to a colour change from colourless-yellow to yellow-red depending on the receptor. In the emission fluorescence, hydrogen bonding interaction is visible through the enhancement of the emission band, whereas deprotonation induced the growth of a new red-shifted emission. The chromo-fluorogenic behaviour could be explained on the basis of the deprotonation tendency of the binding sites and the proton affinity of the anions. PM3 and 1H NMR calculations are in agreement with the existence of the dual complexation-deprotonation process, whereas both studies are in discrepancy in relation to which is the proton involved in the deprotonation. Electrochemical studies carried with receptor 3 showed a quite complex redox behaviour and anodic shifts of the reduction peaks in the presence of the basic anions fluoride, cyanide and acetate.Fundação para a Ciência e a Tecnologia (FCT