Although high-throughput RNA sequencing (RNA-seq) has greatly advanced small non-coding RNA (sncRNA) discovery, the currently widely used complementary DNA library construction protocol generates biased sequencing results. This is partially due to RNA modifications that interfere with adapter ligation and reverse transcription processes, which prevent the detection of sncRNAs bearing these modifications. Here, we present PANDORA-seq (panoramic RNA display by overcoming RNA modification aborted sequencing), employing a combinatorial enzymatic treatment to remove key RNA modifications that block adapter ligation and reverse transcription. PANDORA-seq identified abundant modified sncRNAs-mostly transfer RNA-derived small RNAs (tsRNAs) and ribosomal RNA-derived small RNAs (rsRNAs)-that were previously undetected, exhibiting tissue-specific expression across mouse brain, liver, spleen and sperm, as well as cell-specific expression across embryonic stem cells (ESCs) and HeLa cells. Using PANDORA-seq, we revealed unprecedented landscapes of microRNA, tsRNA and rsRNA dynamics during the generation of induced pluripotent stem cells. Importantly, tsRNAs and rsRNAs that are downregulated during somatic cell reprogramming impact cellular translation in ESCs, suggesting a role in lineage differentiation.RNA modifications, warrant future extensive investigations in different systems.

Human embryogenesis entails complex signalling interactions between embryonic and extra-embryonic cells. However, how extra-embryonic cells direct morphogenesis within the human embryo remains largely unknown due to a lack of relevant stem cell models. Here, we have established conditions to differentiate human pluripotent stem cells (hPSCs) into yolk sac-like cells (YSLCs) that resemble the post-implantation human hypoblast molecularly and functionally. YSLCs induce the expression of pluripotency and anterior ectoderm markers in human embryonic stem cells (hESCs) at the expense of mesoderm and endoderm markers. This activity is mediated by the release of BMP and WNT signalling pathway inhibitors, and, therefore, resembles the functioning of the anterior visceral endoderm signalling centre of the mouse embryo, which establishes the anterior-posterior axis. Our results implicate the yolk sac in epiblast cell fate specification in the human embryo and propose YSLCs as a tool for studying post-implantation human embryo development in vitro.

Muscle satellite stem cells (MuSCs) are responsible for skeletal muscle growth and regeneration. Despite their differentiation potential, human MuSCs have limited in vitro expansion and in vivo migration capacity, limiting their use in cell therapies for diseases affecting multiple skeletal muscles. Several protocols have been developed to derive MuSC-like progenitors from human induced pluripotent stem (iPS) cells (hiPSCs) to establish a source of myogenic cells with controllable proliferation and differentiation. However, current hiPSC myogenic derivatives also suffer from limitations of cell migration, ultimately delaying their clinical translation. Here we use a multidisciplinary approach including bioinformatics and tissue engineering to show that DLL4 and PDGF-BB improve migration of hiPSCderived myogenic progenitors. Transcriptomic analyses demonstrate that this property is conserved across species and multiple hiPSC lines, consistent with results from single cell motility profiling. Treated cells showed enhanced trans-endothelial migration in transwell assays. Finally, increased motility was detected in a novel humanised assay to study cell migration using 3D artificial muscles, harnessing advanced tissue modelling to move hiPSCs closer to future muscle gene and cell therapies.

Poverty and inequality are both the starting point, and the ultimate outcome, for most neglected tropical diseases (NTDs). As a group of 20 diseases, NTDs are typified by their prevalence among the poor, excluded, and marginalised within society. In the absence of quality healthcare provision, many NTDs lead to long term disability, disfigurement, and stigma, which in turn act to reinforce the exclusion and poverty experienced by the afflicted. The path leading to illness is often determined by a widespread lack of access to formal education, timely healthcare, adequate living conditions, employment and nutrition. The reasons for such deprivation are complicated, but ultimately reduce to a persistence of inequalities in affected regions. These inequalities can manifest differently depending on the demographic being studied: gender, ethnicity, geographic location, level of formal education, can all determine the ease with which NTDs are transmitted, diagnosed or treated. Yet, regardless of contextual differences, NTDs continue to persist because individuals within endemic regions experience a healthcare system that is, either directly or indirectly, inequitable. The healthcare system referred to in this context is not confined to simply formal healthcare settings. Rather, it encompasses local healers, community healthcare professionals or volunteers, drug administration programmes, community mental health provision, the formal education system, and, in extension, even the infrastructure that exists to physically connect individuals to their healthcare provider. Failing to ensure parity across each of these components for every citizen equates to a discriminatory healthcare system which fails to recognise the individual’s basic human right to “a standard of living adequate for the health and well-being of themselves and of their family, including food, clothing, housing and medical care and necessary social services” (Article 25- Universal Declaration of Human Rights). To ensure NTDs are managed in a way that is sustainable in the long term, the underlying societal inequalities which allow them to persist must be first understood.

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