Cell最新文献

Exploring targeted therapies for esophageal squamous cell carcinoma (ESCC) remains challenging. Although investigating the roles and therapeutic applications of liquid-liquid phase separation (LLPS) is increasingly of interest, its relationship with ESCC remains unclear. After improving the assay for transposase-accessible chromatin using sequencing (ATAC-seq) protocol for limited-amount clinical samples, we unravel transcription factor AP-2 beta (TFAP2β) as a key downregulated transcription factor (TF) through combined chromatin accessibility and gene expression analyses with cancerous and paracancerous tissues from early-stage ESCC patients. TFAP2β undergoes condensation in the nucleus to bind the zinc finger protein 131 (ZNF131) promoter, thereby inhibiting ZNF131 expression and ESCC progression. The other two crucial downregulated TFs uncovered are incorporated into TFAP2β condensates to bind their corresponding target, suggesting that LLPS may be a hallmark of ESCC transcription. In addition, we obtained compound A6 that mediates intrinsically disordered region conformational changes to enhance TFAP2β condensation and specific ESCC suppression in cells, mice, and patient-derived organoids. Thus, we indicate an LLPS-mediated transcriptional mechanism and a potential therapeutic approach for ESCC.

Myocardial infarction (MI) triggers adverse cardiac events, immune responses, and nervous system activation, but the neural and neuroimmune mechanisms remain understudied. Using single-cell RNA sequencing (scRNA-seq) and tissue clearing, we identified transient receptor potential vanilloid-1 (TRPV1)-expressing vagal sensory neurons (VSNs) that increase ventricular innervation post MI. Ablating these VSNs mitigated MI pathology, reducing infarct size, abnormal electrocardiograms, cardiac dysfunction, sympathetic innervation, and pro-inflammatory cytokine interleukin 1β (IL-1β). Single-nuclei RNA-seq (snRNA-seq) and spatial transcriptomics revealed reduced border zone expansion in MI hearts following VSN ablation. Tracing the effects to the brain, we found that MI activated angiotensin II receptor type 1 (AT1aR)-expressing neurons in the paraventricular nucleus (PVN), whose inhibition mirrored benefits of TRPV1 VSN ablation. Additionally, the superior cervical ganglia (SCGs) exhibited intensified post-MI sympathetic innervation and IL-1β signaling. Blocking IL-1β in the SCG significantly reduced complications post MI. This study reveals a triple-node heart-brain loop underlying MI and potential therapeutic targets.

The small intestinal epithelium represents the most rapidly self-renewing adult mammalian tissue, with a turnover time of 1-2 weeks. It contains ∼12 easily recognizable cell types with a wide diversity of functions, including nutrient absorption, mucus production, antimicrobial defense, and the regulation of metabolism by incretins like Glp1. The simple and repetitive crypt-villus architecture allows for easily interpretable experimentation in transgenic mice in vivo, while the human stem cell hierarchy is experimentally accessible in epithelial organoids in vitro. This review aims to comprehensively describe the design, the cellular constituents, and the molecular regulation of crypt-villus epithelial self-renewal. More generally, it highlights deviations from commonly held views on tissue stem cell biology: gut stem cells divide continually and symmetrically. They can be expanded indefinitely in vitro, while the plasticity of daughter cells can recreate stem cells during regeneration.

Although N⁶-methyladenosine (m⁶A) is a pervasive RNA modification essential for gene regulation, dissecting the functions of individual m⁶A sites remains technically challenging. To overcome this, we developed functional m⁶A sites detection by CRISPR-dCas13b-FTO screening (FOCAS), a CRISPR-dCas13b-based platform enabling high-throughput, site-specific functional screening of m⁶A. Applying FOCAS to four human cancer cell lines identified 4,475 m⁶A-regulated genes influencing cell fitness via both mRNAs and non-coding RNAs (ncRNAs), many of which are newly linked to cancer and exhibit dynamic developmental expression. FOCAS uncovered context-dependent and reader-specific effects of m⁶A within the same gene, revealing its intricate regulatory logic. We further uncovered universal and cell-type-specific m⁶A patterns, with unique sites enriched in ncRNAs and universal ones in transcription-related genes. In SMMC-7721 cells, we identified m⁶A-regulated transcriptional networks that demonstrated extensive epitranscriptome-transcriptome crosstalk. Overall, this study established a powerful, unbiased approach for the functional dissection of m⁶A, advancing the understanding of its complexity and therapeutic relevance in cancers.

Delivery of therapeutic genes is essential for successful gene therapy. Adeno-associated viruses (AAVs) are a prime vector for carrying gene cargoes. However, the limited packaging capacity of AAVs poses a major challenge for large gene transduction. Here, we devised a strategy termed AAV with translocation linkage (AAVLINK), leveraging Cre/lox-mediated intermolecular DNA recombination to overcome cargo size constraints. This AAVLINK strategy enabled superior gene segmentation flexibility, robust gene reconstitution efficiency, and a marked reduction in truncated protein products. AAVLINK drove expression of intact Shank3 or SCN1A and rescued behavior and seizure phenotypes of mutant mice, respectively. Moreover, we generated AAVLINK2.0 with destabilized Cre to address biosafety concerns. Importantly, we used AAVLINK to build a vector bank for 193 large genetic-disorder-associated genes and 5 CRISPR-based tools with verified gene reconstitution. Altogether, our study establishes a robust method to facilitate delivery of large gene cargoes using AAVs.

A typical neuron signals to downstream cells when it is depolarized and fires sodium spikes. Some neurons, however, also fire calcium spikes when hyperpolarized. The function of such bidirectional signaling remains unclear in most circuits. Here, we show how a neuron class that participates in vector computation in the fly central complex employs hyperpolarization-elicited calcium spikes to invert two-dimensional mathematical vectors. By switching from firing sodium to calcium spikes, these neurons implement a ∼180° realignment between the vector encoded in the neuronal population and the fly's internal compass signal, thus inverting the vector. We show that calcium spikes rely on the T-type calcium channel Ca-α1T and argue via analytical and experimental approaches that these spikes enable vector computations in portions of angular space that would otherwise be inaccessible. These results reveal a seamless interaction between molecular, cellular, and circuit properties for implementing vector mathematics in the brain.

In this issue of Cell, Lin et al. present a new adeno-associated virus (AAV)-based toolbox that enables efficient expression of full-length proteins exceeding the conventional single-vector packaging limit. This technology overcomes key limitations of existing dual AAV vector strategies and broadens the applicability of AAV-mediated gene replacement and gene editing strategies to a wider range of genetic disorders.