The inferior colliculus (IC) of the bank vole is made up of 3 nuclei: the external and pericentral nucleus, which are located on the outer border of the IC, and the central nucleus, which is the largest part of IC and shows a laminated structure. On the basis of various morphological criteria 5 types of neurons have been distinguished in the bank vole IC: 1. The rounded cells (perikarya 10-15 m...

Several recent models for spindle length regulation propose an elastic pole to pole spindle matrix that is sufficiently strong to bear or antagonize forces generated by microtubules and microtubule motors. We tested this hypothesis using microneedles to skewer metaphase spindles in Xenopus laevis egg extracts. Microneedle tips inserted into a spindle just outside the metaphase plate resulted in...

BACKGROUND The LC Polscope facilitates visualization of the meiotic spindle in human oocyte. This study aimed to investigate meiotic spindle assembly in correlation to time elapsed after HCG administration, and to determine whether spindle imaging may serve to indicate the likelihood of fertilization and embryo cleavage. METHODS Metaphase II (MII) oocytes from 103 couples who were being treat...

Very low concentrations of paclitaxel, a clinically active anticancer agent isolated from the bark of the Pacific yew tree, were found to produce micronuclei in human colon carcinoma cells, suggesting inhibition of mitotic spindle assembly or function. The possibility that paclitaxel acts at the level of the mitotic spindle was investigated by evaluating its ability to inhibit the progression o...

Microtubules of the mitotic spindle in mammalian somatic cells are focused at spindle poles, a process thought to include direct capture by astral microtubules of kinetochores and/or noncentrosomally nucleated microtubule bundles. By construction and analysis of a conditional loss of mitotic function allele of the nuclear mitotic apparatus (NuMA) protein in mice and cultured primary cells, we d...

The mitotic spindle consists of a complex network of proteins that segregates chromosomes in eukaryotes. To strengthen our understanding of the molecular composition, organization, and regulation of the mitotic spindle, we performed a system-wide two-hybrid screen on 94 proteins implicated in spindle function in Saccharomyces cerevisiae. We report 604 predominantly novel interactions that were ...

The spindle checkpoint monitors mitotic spindle integrity and the attachment of kinetochores to the spindle. Upon sensing a defect the checkpoint blocks cell cycle progression and thereby prevents chromosome missegregation. Previous studies in budding yeast show that the activated spindle checkpoint inhibits the onset of anaphase by an unknown mechanism. One possible target of the spindle check...

The interaction between centrosomes and mitotic spindle poles is important for efficient spindle formation, orientation, and cell polarity. However, our understanding of the dynamics of this relationship and implications for tissue homeostasis remains poorly understood. Here we report that Drosophila melanogaster calmodulin (CaM) regulates the ability of the microcephaly-associated protein, abn...

The spindle assembly checkpoint (SAC) maintains genomic integrity by preventing progression of mitotic cell division until all chromosomes are stably attached to spindle microtubules. The SAC critically relies on the paralogues Bub1 and BubR1/Mad3, which integrate kinetochore-spindle attachment status with generation of the anaphase inhibitory complex MCC. We previously reported on the widespre...

Very low concentrations of paclitaxel, a clinically active anticancer agent isolated from the bark of the Pacific yew tree, were found to produce micronuclei in human colon carcinoma cells, suggesting inhibition of mitotic spindle assembly or function. The possibility that paclitaxel acts at the level of the mitotic spindle was investigated by evaluating its ability to inhibit the progression o...