Roughly half of all animal somatic cell spindles assemble by the classical prophase pathway, in which the centrosomes separate ahead of nuclear envelope breakdown (NEBD). The remainder assemble by the prometaphase pathway, in which the centrosomes separate following NEBD. Why cells use dual pathway spindle assembly is unclear. Here, by examining the timing of NEBD relative to the onset of Eg5-m...

Abstract Aerostatic spindles are used in precision grinding applications requiring high stiffness and very low error motions (5 to 25 nm). Forces generated during precision grinding are small and present challenges for accurate and reliable process monitoring. These challenges are met by incorporating non-contact displacement sensors into an aerostatic spindle that are calibrated to measure gri...

Formation of one procentriole next to each pre-existing centriole is essential for centrosome duplication, robust bipolar spindle assembly and maintenance of genome integrity. However, the mechanisms maintaining strict control over centriole copy number are incompletely understood. Here we show that Plk4 and STIL, the key regulators of centriole formation, form a protein complex that provides a...

Background: The meiotic spindle plays an important role in the oocyte during chromosome alignment and separation at meiosis. The zona pellucid (ZP) is a dynamic matrix composed of filaments with the properties that might reflect the history of oocyte cytoplasmic maturation. Since, spindle and ZP in living oocytes are highly birefringent, their structures can be viewed noninvasively by using a P...

OBJECTIVE Sleep spindles (12-15 Hz oscillations) are one of the hallmarks of the electroencephalogram (EEG) during human non-rapid eye movement (non-REM) sleep. The effect of a 40 h sleep deprivation (SD) on spindle characteristics along the antero-posterior axis was investigated. METHODS EEGs during non-REM sleep in healthy young volunteers were analyzed with a new method for instantaneous s...

The concept of a spindle matrix has long been proposed. Whether such a structure exists, however, and what its molecular and structural composition are have remained controversial. In this study, using a live-imaging approach in Drosophila syncytial embryos, we demonstrate that nuclear proteins reorganize during mitosis to form a highly dynamic, viscous spindle matrix that embeds the microtubul...

INTRODUCTION During anaphase B in mitosis, polymerization and sliding of overlapping spindle microtubules (MTs) contribute to the outward movement the spindle pole bodies (SPBs). To probe the mechanism of spindle elongation, we combine fluorescence microscopy, photobleaching, and laser microsurgery in the fission yeast Schizosaccharomyces pombe. RESULTS We demonstrate that a green laser cuts ...

  Background and Objective: Inflammatory pseudotumor  is a lesion composed of proliferating spindle cells with mixed inflammatory infiltrates. Some authors have proposed the name inflammatory myofibroblastic tumor as a proper descriptive term rather than the vague inflammatory pseudotumor. The aim of this study was to verify the myofibroblastic origin of spindle cells in idiopathic orbital inf...

We have used micromanipulation to study the attachment of chromosomes to the spindle and the mechanical properties of the chromosomal spindle fibers . Individual chromosomes can be displaced about the periphery of the spindle, in the plane of the metaphase plate, without altering the structure ofthe spindle or the positions of the nonmanipulated chromosomes . From mid-prometaphase through the o...

Just as the size of an organism is carefully controlled, the size of intracellular structures must also be regulated. The mitotic spindle is a supramolecular machine that generates the forces which separate sister chromatids during mitosis. Although spindles show little size variation between cells of the same type, spindle length can vary at least 10-fold between different species. Recent expe...