Cytoplasmic microtubules exist as distinct dynamic and stable populations within the cell. Stable microtubules direct and maintain cell polarity and it is thought that their stabilization is dependent on coordinative organization between the microtubule network and the actin cytoskeleton. A growing body of work suggests that some members of the formin family of actin remodeling proteins also re...

Microtubule assembly is vital for many fundamental cellular processes. Current models for microtubule assembly kinetics assume that the subunit dissociation rate from a microtubule tip is independent of free subunit concentration. Total-Internal-Reflection-Fluorescence (TIRF) microscopy experiments and data from a laser tweezers assay that measures in vitro microtubule assembly with nanometer r...

Mechanisms controlling microtubule dynamics at the cell cortex play a crucial role in cell morphogenesis and neuronal development. Here, we identified kinesin-4 KIF21A as an inhibitor of microtubule growth at the cell cortex. In vitro, KIF21A suppresses microtubule growth and inhibits catastrophes. In cells, KIF21A restricts microtubule growth and participates in organizing microtubule arrays a...

Dynamic microtubule ends exert pulling and pushing forces on intracellular membranes and organelles. However, the mechanical linkage of microtubule tips to their cargoes is poorly understood. CENP-F is a nonmotor microtubule-binding protein that participates in microtubule binding at kinetochores and in the mitotic redistribution of the mitochondrial network. CENP-F-driven mitochondrial transpo...

Background: Effect of different doses of cysteamine on rate of in vitro maturation (IVM), in vitro fertilization (IVF) and glutathione (GSH) level was studied. Metaphase II (MII) spindle area was analyzed for quantification of shape and size of oocytes. Methods: Female mice were primed with 5 IU of pregnant mare’s stimulating gonadotrophin. Germinal vesicle (GV) oocytes were retrieved 48 hrs la...

A steady-state metaphase spindle maintains constant length, although the microtubules undergo intensive dynamics. Tubulin dimers are incorporated at plus ends of spindle microtubules while they are removed from the minus ends, resulting in poleward movement. Such microtubule flux is regulated by the microtubule rescue factors CLASPs at kinetochores and depolymerizing protein Kif2a at the poles,...

Dynamic microtubules facilitate chromosome arrangement before anaphase, whereas during anaphase microtubule stability assists chromosome separation. Changes in microtubule dynamics at the metaphase-anaphase transition are regulated by Cdk1. Cdk1-mediated phosphorylation of Sli15/INCENP promotes preanaphase microtubule dynamics by preventing chromosomal passenger complex (CPC; Sli15/INCENP, Bir1...

Human EB1 was originally cloned as a protein that interacts with the COOH terminus of adenomatous polyposis coli (APC). Interestingly, this interaction is often disrupted in colon cancer, due to mutations in APC. EB1 also interacts with the plus-ends of microtubules and targets APC to microtubule tips. Since APC is detected on the kinetochores of chromosomes, it has been hypothesized that the E...

Abstract The cytoskeleton is a major focus of physical studies to understand organization inside cells given its primary role in cell motility, division, and mechanics. Recently, protein condensation has been shown be another intracellular organizational strategy. Here, we report that the microtubule crosslinking proteins, MAP65-1 PRC1, can form phase separated condensates at physiological salt...

ABSTRACT Binyam Mogessie was born and raised in Ethiopia. He moved to Germany 2004, where he studied biochemistry cell biology at Jacobs University Bremen. then the UK for his PhD with Anne Straube, first Marie Curie Research Institute Surrey later Centre Mechanochemical Cell Biology Warwick, investigated cellular mechanisms that organise microtubule cytoskeleton during skeletal muscle differen...