Trends in Cell Biology最新文献

Cellular metabolism is intricately regulated by redox signaling, with the NADH/NAD⁺ couple serving as a central hub. Emerging evidence reveals that NADH reductive stress, marked by NADH accumulation, is not merely a passive byproduct of metabolic dysfunction but an active regulatory signal driving metabolic reprogramming. In this Review, we synthesize recent advances in understanding NADH reductive stress, including its origins, regulatory mechanism, and manipulation. We examine its broad impact on cellular metabolism, its interplay with oxidative and energy stress, and its pathogenic roles in a range of diseases. By integrating these findings, we propose NADH reductive stress as a master regulator for metabolic reprogramming and highlight new avenues for mechanistic exploration and therapeutic intervention.

Lipids are major cell constituents endowed with astonishing structural diversity. The pathways responsible for the assembly and disposal of different lipid species are energetically demanding, and genes encoding lipid metabolic factors and lipid-related proteins comprise a sizable fraction of our coding genome. Despite the importance of lipids, the biological significance of lipid structural diversity remains largely obscure. Recent technological developments have enabled extensive lipid analysis at the single cell level, revealing unexpected cell-cell variability in lipid composition. This new evidence suggests that lipid diversity is exploited in multicellularity and that lipids have a role in the establishment and maintenance of cell identity. In this review, we highlight the emerging concepts and technologies in single cell lipid analysis and the implications of this research for future studies.

Peroxisomes are cellular organelles that are crucial for metabolism, stress responses, and healthy aging. They have recently come to be considered as important mediators of the immune response during viral infections. Consequently, various viruses target peroxisomes for the purpose of hijacking either their biogenesis or their functions, as a means of replicating efficiently, making this a compelling research area. Despite their known connections with mitochondria, which have been the object of considerable research on account of their role in the innate immune response, less is known about peroxisomes in this context. In this review, we explore the evolving understanding of the role of peroxisomes, highlighting recent findings on how they are exploited by viruses to modulate their replication cycle.

Colorectal cancer (CRC) metastasis is driven by phenotypic plasticity beyond classic epithelial-mesenchymal transition (EMT), including non-canonical lineages such as squamous-like phenotypes. Their regulatory mechanisms and clinical significance remain unclear. In the current issue of Nature, Cammareri et al. identified ATRX loss as a driver of multilineage plasticity, including squamous-like characteristics, linked to increased metastasis and poor clinical outcomes in CRC.

Concomitant progress in the fields of microfluidics, microscale molecular biology, next-generation sequencing, and analytical methods for whole transcriptomic datasets has transformed our ability to understand complex cellular state changes at the single-cell level. New cell types have been discovered and cell transition states and intermediate phenotypes have been characterized across diverse developmental and disease contexts. More recently, integrating transcriptomic and epigenomic data has dramatically extended our understanding of transcriptional regulons and gene regulatory networks (GRNs) that determine gene expression and individual cellular phenotypes. Applied to cardiac biology, combined transcriptomic and epigenomic profiling has allowed the characterization of the developmental trajectories and molecular mechanisms that give rise to the diverse cell lineages of the adult heart and contribute to the pathogenesis of genetic diseases. In this review, we present the latest methodological innovations, discuss the computational strategies for multiomic data integration, and highlight how these advances are reshaping our undestanding of heart development and disease mechanisms.

Cellular homeostasis declines with age due to the declining fidelity of biosynthetic processes and the accumulation of molecular damage. Yet, it remains largely elusive how individual processes are affected during aging and what their specific contribution to age-related functional decline is. This review discusses a series of recent publications that has shown that transcription elongation is compromised during aging due to increasing DNA damage, stalling of RNA polymerase II (RNAPII), erroneous transcription initiation in gene bodies, and accelerated RNAPII elongation. Importantly, several of these perturbations likely arise from changes in chromatin organization with age. Thus, taken together, this work establishes a network of interlinked processes contributing to age-related decline in the quantity and quality of RNA production.

The ability of a cell to properly express its genes depends on optimal transcription and splicing. RNA polymerase II (RNAPII) transcribes protein-coding genes and produces pre-mRNAs, which undergo, largely co-transcriptionally, intron excision by the spliceosome complex. Spliceosome activation is a major control step, leading to a catalytically active complex. Recent work has showed that cyclin-dependent kinase (CDK)11 regulates spliceosome activation via the phosphorylation of SF3B1, a core spliceosome component. Thus, CDK11 arises as a major coordinator of gene expression in metazoans due to its role in the rate-limiting step of pre-mRNA splicing. This review outlines the evolution of CDK11 and SF3B1 and their emerging roles in splicing regulation. It also discusses how CDK11 and its inhibition affect transcription and cell cycle progression.

Membrane fission is thought to involve helix-forming proteins to constrict the Ω-shaped profile's neck. Recent studies suggest that membrane pit-coating proteins, especially clathrin, may also mediate fission via polymerization on the Ω-profile's base or head to generate neck constriction, which underlies various endocytic modes previously attributed as clathrin (Ω-profile head) independent.

The nonreceptor tyrosine phosphatases (PTPS) SHP1 and SHP2 have crucial roles in dephosphorylating an array of substrates involved in pathways comprising receptor tyrosine kinases (RTKs) and immune receptors. This regulation maintains a delicate balance between the activation and inhibition of signal transduction, ensuring appropriate biological outcomes. In this review, we summarize research focused on elucidating the functions of SHP1 and SHP2 in hematopoiesis, immune regulation, and tumor biology, emphasizing recent findings related to cancer-driven immune evasion. Furthermore, we highlight the significant effects of SHP1 and SHP2 inhibitors in enhancing cancer treatment, specifically through the facilitation of chemotherapy and augmentation of immune activation.

The tumor microenvironment (TME) is a dynamic and complex ecosystem composed of cancer cells and diverse non-malignant cell types, including immune cells, fibroblasts, and endothelial cells. Once viewed as passive bystanders, these host cells are now recognized as active participants in tumor progression, especially during metastasis. The TME varies by organ, cancer type, and disease stage, and shapes the trajectory of cancer progression. Among the immune cells in the TME, macrophages, neutrophils, and T cells play especially crucial and context-dependent roles - either promoting or inhibiting metastatic spread depending on the tumor stage, immune cell phenotypic states, and interactions. In this review we focus on the multifaceted contributions of these key immune populations across the major stages of the metastatic cascade: initiation, survival in the circulation, dissemination, dormancy, and reactivation. These insights highlight the heterogeneity of the metastatic immune microenvironment and underscore the therapeutic potential of targeting macrophages, neutrophils, and T cells to combat metastatic disease.