The involvement of acidic nucleoplasmic DNA-binding protein (and-1) in the regulation of prereplicative complex (pre-RC) assembly in human cells

DNA replication in all eukaryotes starts with the process of loading the replicative helicase MCM2–7 onto chromatin during late mitosis of the cell cycle. MCM2–7 is a key component of the prereplicative complex (pre-RC), which is loaded onto chromatin by the concerted action of origin recognition complex, Cdc6, and Cdt1. Here, we demonstrate that And-1 is assembled onto chromatin in late mitosis and early G(1) phase before the assembly of pre-RC in human cells. And-1 forms complexes with MCM2–7 to facilitate the assembly of MCM2–7 onto chromatin at replication origins in late mitosis and G(1) phase. We also present data to show that depletion of And-1 significantly reduces the interaction between Cdt1 and MCM7 in G(1) phase cells. Thus, human And-1 facilitates loading of the MCM2–7 helicase onto chromatin during the assembly of pre-RC

Experimental study of solubility of elemental sulphur in methane

International audienceThe chemical engineering department of LaTEP has been working for many years on theproblem of sulphur deposition especially in natural gas network [1, 2]. The solid sulphurappears immediately downstream of a pressure reduction facility. One of the hypothesesproposed to explain the solid formation, based on a thermodynamic approach, is thedesublimation of sulphur. During gas expansion, both pressure and temperature decrease.Consequently the gas may become over saturated in sulphur. Because we are below thetemperature of sulphur triple point, part of the gaseous sulphur can be transformed into solidparticles. Thus, it is important to obtain solubility data of sulphur in natural gases. Methane isthe major natural gas component. So, it is of importance to measure solubility of elementalsulphur in CH4. In this paper experimental measurements up to a pressure and temperature of30 MPA and 363.15 K are presented.The principle of the experimental pilot can be resumed following three steps: saturationof the gas with sulphur, trap of all the dissolved gaseous sulphur and finally quantification.Although the principle is simple, experimental difficulties occur at the three steps. A variablevolume equilibrium cell is used to saturate the gas with sulphur. Since sulphur solubility valueis weak in gas transport conditions, the volume of the cell is necessarily big (0.5 Litre). Thepressure of the equilibrium cell is held constant thanks to a piston during the trapping step. Anoriginal gaseous sulphur trapping method was developed. It is based on the reactiveabsorption of the gaseous sulphur with solvent. Indeed, the gas bubbles into a liquid solutionwhich traps gaseous sulphur. Finally, the solution which contains a standard is analysed bygas chromatography and sulphur is quantified. The total volume of the gas withdrawn isdetermined by a position transducer placed on the autoclave. Then, the sulphur solubilityvalue is calculated

Loss of Cyclin C or CDK8 provides ATR inhibitor resistance by suppressing transcription-associated replication stress.

The protein kinase ATR plays pivotal roles in DNA repair, cell cycle checkpoint engagement and DNA replication. Consequently, ATR inhibitors (ATRi) are in clinical development for the treatment of cancers, including tumours harbouring mutations in the related kinase ATM. However, it still remains unclear which functions and pathways dominate long-term ATRi efficacy, and how these vary between clinically relevant genetic backgrounds. Elucidating common and genetic-background specific mechanisms of ATRi efficacy could therefore assist in patient stratification and pre-empting drug resistance. Here, we use CRISPR-Cas9 genome-wide screening in ATM-deficient and proficient mouse embryonic stem cells to interrogate cell fitness following treatment with the ATRi, ceralasertib. We identify factors that enhance or suppress ATRi efficacy, with a subset of these requiring intact ATM signalling. Strikingly, two of the strongest resistance-gene hits in both ATM-proficient and ATM-deficient cells encode Cyclin C and CDK8: members of the CDK8 kinase module for the RNA polymerase II mediator complex. We show that Cyclin C/CDK8 loss reduces S-phase DNA:RNA hybrid formation, transcription-replication stress, and ultimately micronuclei formation induced by ATRi. Overall, our work identifies novel biomarkers of ATRi efficacy in ATM-proficient and ATM-deficient cells, and highlights transcription-associated replication stress as a predominant driver of ATRi-induced cell death

Mediators of the Link Between Autistic Traits and Relationship Satisfaction in a Non-Clinical Sample

People with ASD have deficits in their social skills and may therefore experience lower relationship satisfaction. This study investigated possible mechanisms to explain whether and how autistic traits, measured with the AQ, influence relationship satisfaction in a non-clinical sample of 195 married couples. More autistic traits were associated with lower relationship satisfaction for husbands but not for wives. Multiple mediation analyses revealed that husbands’ responsiveness towards their wives, trust, and intimacy mediated this link between autistic traits and relationship satisfaction. These findings suggest that autistic traits may hamper men’s relationship satisfaction because they impede relationship-specific feelings and behavior. There was no partner-effect of autistic traits, indicating that more autistic traits do not necessarily influence the partner’s perceptions of relationship satisfaction

Experiences of Receiving a Diagnosis of Autism Spectrum Disorder: A Survey of Adults in the United Kingdom

A total of 128 adults with high-functioning autism spectrum disorders were surveyed concerning the process they went through to obtain their diagnosis and the subsequent support they received. Results suggested that routes to diagnosis were quite heterogeneous and overall levels of satisfaction with the diagnostic process were mixed; 40 % of respondents were ‘very/quite’ dissatisfied, whilst 47 % were ‘very/quite’ satisfied. The extent of delays, number of professionals seen, quality of information given at diagnosis and levels of post-diagnostic support predicted overall satisfaction with the diagnostic process. Important areas and suggestions for improvement were noted for all stages of the diagnostic pathway. Respondents also displayed above average levels of depressed mood and anxiety, with greater support being requested in this area

DIA1R Is an X-Linked Gene Related to Deleted In Autism-1

Background: Autism spectrum disorders (ASDs) are frequently occurring disorders diagnosed by deficits in three core functional areas: social skills, communication, and behaviours and/or interests. Mental retardation frequently accompanies the most severe forms of ASDs, while overall ASDs are more commonly diagnosed in males. Most ASDs have a genetic origin and one gene recently implicated in the etiology of autism is the Deleted-In-Autism-1 (DIA1) gene. Methodology/Principal Findings: Using a bioinformatics-based approach, we have identified a human gene closely related to DIA1, we term DIA1R (DIA1-Related). While DIA1 is autosomal (chromosome 3, position 3q24), DIA1R localizes to the X chromosome at position Xp11.3 and is known to escape X-inactivation. The gene products are of similar size, with DIA1 encoding 430, and DIA1R 433, residues. At the amino acid level, DIA1 and DIA1R are 62 % similar overall (28 % identical), and both encode signal peptides for targeting to the secretory pathway. Both genes are ubiquitously expressed, including in fetal and adult brain tissue. Conclusions/Significance: Examination of published literature revealed point mutations in DIA1R are associated with X-linked mental retardation (XLMR) and DIA1R deletion is associated with syndromes with ASD-like traits and/or XLMR. Together, these results support a model where the DIA1 and DIA1R gene products regulate molecular traffic through the cellular secretory pathway or affect the function of secreted factors, and functional deficits cause disorders with ASD-lik