Publications by authors named "Songlei Liu"

The GATOR2-GATOR1 signaling axis is essential for amino-acid-dependent mTORC1 activation. However, the molecular function of the GATOR2 complex remains unknown. Here, we report that disruption of the Ring domains of Mios, WDR24, or WDR59 completely impedes amino-acid-mediated mTORC1 activation.

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Whole-genome recoding has been shown to enable nonstandard amino acids, biocontainment and viral resistance in bacteria. Here we take the first steps to extend this to human cells demonstrating exceptional base editing to convert TAG to TAA for 33 essential genes via a single transfection, and examine base-editing genome-wide (observing ~40 C-to-T off-target events in essential gene exons). We also introduce GRIT, a computational tool for recoding.

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Cerebral organoids can be used to gain insights into cell type specific processes perturbed by genetic variants associated with neuropsychiatric disorders. However, robust and scalable phenotyping of organoids remains challenging. Here, we perform RNA sequencing on 71 samples comprising 1,420 cerebral organoids from 25 donors, and describe a framework (Orgo-Seq) to integrate bulk RNA and single-cell RNA sequence data.

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The generation of organoids and tissues with programmable cellular complexity, architecture and function would benefit from the simultaneous differentiation of human induced pluripotent stem cells (hiPSCs) into divergent cell types. Yet differentiation protocols for the overexpression of specific transcription factors typically produce a single cell type. Here we show that patterned organoids and bioprinted tissues with controlled composition and organization can be generated by simultaneously co-differentiating hiPSCs into distinct cell types via the forced overexpression of transcription factors, independently of culture-media composition.

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Gene activation with the CRISPR-Cas system has great implications in studying gene function, controlling cellular behavior, and modulating disease progression. In this review, we survey recent studies on targeted gene activation and multiplexed screening for inducing neuronal differentiation using CRISPR-Cas transcriptional activation (CRISPRa) and open reading frame (ORF) expression. Critical technical parameters of CRISPRa and ORF-based strategies for neuronal programming are presented and discussed.

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Coronavirus disease 2019 (COVID-19) continues to burden society worldwide. Despite most patients having a mild course, severe presentations have limited treatment options. COVID-19 manifestations extend beyond the lungs and may affect the cardiovascular, nervous, and other organ systems.

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We present barcoded oligonucleotides ligated on RNA amplified for multiplexed and parallel insitu analyses (BOLORAMIS), a reverse transcription-free method for spatially-resolved, targeted, in situ RNA identification of single or multiple targets. BOLORAMIS was demonstrated on a range of cell types and human cerebral organoids. Singleplex experiments to detect coding and non-coding RNAs in human iPSCs showed a stem-cell signature pattern.

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Methods for highly multiplexed RNA imaging are limited in spatial resolution and thus in their ability to localize transcripts to nanoscale and subcellular compartments. We adapt expansion microscopy, which physically expands biological specimens, for long-read untargeted and targeted in situ RNA sequencing. We applied untargeted expansion sequencing (ExSeq) to the mouse brain, which yielded the readout of thousands of genes, including splice variants.

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Background: Radiofrequency of the Gasserian ganglion can be used for ophthalmic herpetic neuralgia (OHN), but it is associated with complications. This study aimed to use the supraorbital nerve for computed tomography- (CT-) guided radiofrequency thermocoagulation to treat refractory OHN.

Methods: This was a retrospective case series study of patients with simple or combined OHN treated at our hospital between 06/2012 and 06/2018.

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Herpes zoster (HZ), commonly called shingles, it is a distinctive syndrome caused by reactivation of varicella zoster virus (VZV). A better understanding of the biological characteristics of HZ patients can help develop new targeted therapies to improve the prognosis. High-throughput proteomics technology can deeply study the molecular changes in the development and progression of HZ disease and integrate different levels of information, this is important to help make clinical decisions.

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Bone cancer pain (BCP) is an intractable clinical problem, and lacked effective drugs for treating it. Recent research showed that several chemokines in the spinal cord are involved in the pathogenesis of BCP. In this study, the antinociceptive effects of liquiritin, which is an active component extracted from Glycyrrhizae Radix, were tested and the underlying mechanisms targeting spinal dorsal horn (SDH) were investigated.

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Background: Primary V1 trigeminal neuralgia is a common refractory neuralgia in clinical practice, lacking effective treatments. Radiofrequency therapy has certain treatment efficacy, but its long-term efficacy remained poor and the disease might relapse.

Objective: To compare the effects of different types of supraorbital foramen variations on the treatment efficacy of radiofrequency therapy for V1 trigeminal neuralgia.

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The feature extraction of protein sequences is a challenging problem. It might need a lot of theoretical and practical knowledge from many fields. The difficulty would increase when investigators extract the features solely from protein sequences.

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