The mitotic spindle is required for chromosome congression and subsequent equal segregation of sister chromatids. These processes involve a complex network of signaling molecules located at the spindle. The endocytic protein, clathrin, has a "moonlighting" role during mitosis, whereby it stabilizes the mitotic spindle. The signaling pathways that clathrin participates in to achieve mitotic spindle stability are unknown. Here, we assessed the mitotic spindle proteome and phosphoproteome in clathrin-depleted cells using quantitative MS/MS (data are available via ProteomeXchange with identifier PXD001603). We report a spindle proteome that consists of 3046 proteins and a spindle phosphoproteome consisting of 5157 phosphosites in 1641 phosphoproteins. Of these, 2908 (95.4%) proteins and 1636 (99.7%) phosphoproteins are known or predicted spindle-associated proteins. Clathrin-depletion from spindles resulted in dysregulation of 121 proteins and perturbed signaling to 47 phosphosites. The majority of these proteins increased in mitotic spindle abundance and six of these were validated by immunofluorescence microscopy. Functional pathway analysis confirmed the reported role of clathrin in mitotic spindle stabilization for chromosome alignment and highlighted possible new mechanisms of clathrin action. The data also revealed a novel second mitotic role for clathrin in bipolar spindle formation.
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http://dx.doi.org/10.1074/mcp.M115.054809 | DOI Listing |
Cell Div
December 2024
Institute for Research in Immunology and Cancer, Département de biochimie et médecine moléculaire, Université de Montréal, Montreal, Québec, Canada.
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December 2024
Department of Tumor Pathology, Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan.
STIL is a regulatory protein essential for centriole biogenesis, and its dysregulation has been implicated in various diseases, including malignancies. However, its role in non-small-cell lung carcinoma (NSCLC) remains unclear. In this study, we examined STIL expression and its potential association with chromosomal numerical abnormalities (CNAs) in NSCLC using The Cancer Genome Atlas (TCGA) dataset, immunohistochemical analysis, and in vitro experiments with NSCLC cell lines designed to overexpress STIL.
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December 2024
Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany; Cell Biology and Biophysics Unit, EMBL, 69117 Heidelberg, Germany. Electronic address:
Centrosomes organize microtubules that are essential for mitotic divisions in animal cells. They consist of centrioles surrounded by pericentriolar material (PCM). Questions related to mechanisms of centriole assembly, PCM organization, and spindle microtubule formation remain unanswered, partly due to limited availability of molecular-resolution structural data inside cells.
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December 2025
Department of Biology, Indian Institute of Science Education & Research, Pune, India.
Proper formation and specification of Primordial Germ Cells (PGCs) is of special significance as they gradually transform into Germline Stem Cells (GSCs) that are ultimately responsible for generating the gametes. Intriguingly, not only the PGCs constitute the only immortal cell type but several specific determinants also underlying PGC specification such as Vasa, Nanos and Germ-cell-less are conserved through evolution. In , PGC formation and specification depends on two independent factors, the maternally deposited specialized cytoplasm (or germ plasm) enriched in germline determinants, and the mechanisms that execute the even partitioning of these determinants between the daughter cells.
View Article and Find Full Text PDFNat Commun
December 2024
Department of Meiosis, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
Aneuploidy in eggs is a leading cause of miscarriages or viable developmental syndromes. Aneuploidy rates differ between individual chromosomes. For instance, chromosome 21 frequently missegregates, resulting in Down Syndrome.
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