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Abstract Background Tuberous sclerosis complex (TSC) is an inherited neurocutaneous disorder caused by mutations in the TSC1 or TSC2 genes, with patients often exhibiting neurodevelopmental (ND) manifestations termed TSC-associated neuropsychiatric disorders (TAND) including autism spectrum disorder (ASD) and intellectual disability. Hamartin (TSC1) and tuberin (TSC2) proteins form a complex inhibiting mechanistic target of rapamycin complex 1 (mTORC1) signaling. Loss of TSC1 or TSC2 activates mTORC1 that, among several targets, controls protein synthesis by inhibiting translational repressor eIF4E-binding proteins. Using TSC1 patient-derived neural progenitor cells (NPCs), we recently reported early ND phenotypic changes, including increased cell proliferation and altered neurite outgrowth in TSC1-null NPCs, which were unaffected by the mTORC1 inhibitor rapamycin. Methods Here, we used polysome profiling, which quantifies changes in mRNA abundance and translational efficiencies at a transcriptome-wide level, to compare CRISPR-edited TSC1-null with CRISPR-corrected TSC1-WT NPCs generated from one TSC donor (one clone/genotype). To assess the relevance of identified gene expression alterations, we performed polysome profiling in postmortem brains from ASD donors and age-matched controls. We further compared effects on translation of a subset of transcripts and rescue of early ND phenotypes in NPCs following inhibition of mTORC1 using the allosteric inhibitor rapamycin versus a third-generation bi-steric, mTORC1-selective inhibitor RMC-6272. Results Polysome profiling of NPCs revealed numerous TSC1-associated alterations in mRNA translation that were largely recapitulated in human ASD brains. Moreover, although rapamycin treatment partially reversed the TSC1-associated alterations in mRNA translation, most genes related to neural activity/synaptic regulation or ASD were rapamycin-insensitive. In contrast, treatment with RMC-6272 inhibited rapamycin-insensitive translation and reversed TSC1-associated early ND phenotypes including proliferation and neurite outgrowth that were unaffected by rapamycin. Conclusions Our work reveals ample mRNA translation alterations in TSC1 patient-derived NPCs that recapitulate mRNA translation in ASD brain samples. Further, suppression of TSC1-associated but rapamycin-insensitive translation and ND phenotypes by RMC-6272 unveils potential implications for more efficient targeting of mTORC1 as a superior treatment strategy for TAND.

Abstract Rocaglates are a class of eukaryotic translation initiation inhibitors that are being explored as chemotherapeutic agents. They function by targeting eukaryotic initiation factor (eIF) 4A, an RNA helicase critical for recruitment of the 40S ribosome (and associated factors) to mRNA templates. Rocaglates perturb eIF4A activity by imparting a gain-of-function activity to eIF4A and mediating clamping to RNA. To appreciate how rocaglates could best be enabled in the clinic, an understanding of resistance mechanisms is important, as this could inform on strategies to bypass such events as well as identify responsive tumor types. Here, we report on the results of a positive selection, ORFeome screen aimed at identifying cDNAs capable of conferring resistance to rocaglates. Two of the most potent modifiers of rocaglate response identified were the transcription factors FOXP3 and NR1I3, both of which have been implicated in ABCB1 regulation—the gene encoding P-glycoprotein (Pgp). Pgp has previously been implicated in conferring resistance to silvestrol, a naturally occurring rocaglate, and we show here that this extends to additional synthetic rocaglate derivatives. In addition, FOXP3 and NR1I3 impart a multi-drug resistant phenotype that is reversed upon inhibition of Pgp, suggesting a potential therapeutic combination strategy.

We report on a recent innovation for one Departmental Select Committee. While government policy commitments are well publicised, little attention is paid to the quality of commitments made or to assessing progress against those commitments. In 2020, the Health and Social Care Select Committee commissioned an Expert Panel to conduct independent, in-depth evaluations of government progress on selected policy commitments. The first evaluations in 2021/22 assessed commitments in maternity, mental health and cancer services, and workforce and it was the first time a government department has been systematically graded against its own commitments. This is an important new method of scrutiny with the potential to complement and enhance the work of Select Committee inquiries. This paper reviews the development of select committees highlighting issues relating to their operation and, in particular, assessment of evidence. We describe the innovation of the Expert Panel and its role in reviewing policy commitments and discuss implications for parliamentary scrutiny, leadership and improvements to health service. [ABSTRACT FROM AUTHOR]

Sociological research has long been interested in inequalities generated by and within educational institutions. Although relatively rich as a literature, less analytic focus has centered on educational mobility and inequality experiences within graduate training specifically. In this article, we draw on a combination of survey and open-ended qualitative data from approximately 450 graduate students in the discipline of sociology to analyze graduate school pipeline divergences for first-generation and working-class students and the implications for inequalities in tangible resources, advising and support, and a sense of isolation. Our results point to an important connection between private undergraduate institutional enrollment and higher-status graduate program attendance—a pattern that undercuts social-class mobility in graduate training and creates notable precarities in debt, advising, and sense of belonging for first-generation and working-class graduate students. We conclude by discussing the unequal pathways revealed and their implications for merit and mobility, graduate training, and opportunity within our and other disciplines. [ABSTRACT FROM AUTHOR]

Transmission teaching which centres around traditional lecturing discounts the variety of different learners and individual aptitudes. Physical Geography as a discipline has historically provided a range of teaching methods beyond lecturing which embrace field and laboratory activities, frequently adapting new research technologies to further student learning. While technological trends are increasing the demand for Geography graduates with GIS, modelling, or programming skills, Geography lecturers should remain open to using other technological advances as teaching tools. Using an example of low-cost environmental sensors, this paper demonstrates how technologically-focused exercises can effectively solidify a range of geographical skills through experiential learning. Using Kolb's Experiential Learning Model to identify the key learning processes, we compare low-cost environmental sensor training to the UK's current Quality Assurance Agency for Higher Education's (QAA) Geography benchmarks. We also consider the practical applications of this technology as a learning tool for Physical Geography. In comparison with a student evaluation, this paper provides an initial basis to support additional qualitative investigations into the learning outcomes of independent, technology-based learning activities. [ABSTRACT FROM AUTHOR]

Metabolic reprogramming is a hallmark of pancreatic ductal adenocarcinoma (PDA). Here, the authors show that in PDA cells redox and central carbon metabolism are driven by an eIF4F dependent translation program, and combined targeting of eIF4A and glutaminase can impact PDA proliferation.

Summary: Rocaglates are a diverse family of biologically active molecules that have gained tremendous interest in recent years due to their promising activities in pre-clinical cancer studies. As a result, this family of compounds has been significantly expanded through the development of efficient synthetic schemes. However, it is unknown whether all of the members of the rocaglate family act through similar mechanisms of action. Here, we present a comprehensive study comparing the biological activities of >200 rocaglates to better understand how the presence of different chemical entities influences their biological activities. Through this, we find that most rocaglates preferentially repress the translation of mRNAs containing purine-rich 5′ leaders, but certain rocaglates lack this bias in translation repression. We also uncover an aspect of rocaglate mechanism of action in which the pool of translationally active eIF4F is diminished due to the sequestration of the complex onto RNA. : Rocaglates are a diverse family of small molecules that inhibit eIF4A. Chu et al. undertake a comparative analysis of the bioactivity of >200 rocaglates and uncover nuances in their mechanisms of action. Rocaglates interfere with eIF4F release from the cap and exert a bystander effect to inhibit translation. Keywords: rocaglates, eIF4A, eIF4F, translation initiation, interfacial inhibitor

Genetically engineered mouse models (GEMMs) are powerful tools by which to probe gene function in vivo, obtain insight into disease etiology, and identify modifiers of drug response. Increased sophistication of GEMMs has led to the design of tissue-specific and inducible models in which genes of interest are expressed or ablated in defined tissues or cellular subtypes. Here we describe the generation of a transgenic mouse harboring a doxycycline-regulated Cas9 allele for inducible genome engineering. This model provides a flexible platform for genome engineering since editing is achieved by exogenous delivery of sgRNAs and should allow for the modeling of a range of biological and pathological processes.