XMAP230 is a high molecular mass microtubule-associated protein isolated from Xenopus oocytes and eggs, and has been recently shown to be a homolog of mammalian MAP4. Confocal immunofluorescence microscopy revealed that XMAP230 is associated with microtubules throughout the cell cycle of early Xenopus embryos. During interphase XMAP230 is associated with the radial arrays of microtubules and mi...

When higher eukaryotic cells enter mitosis, membrane organization changes dramatically and traffic between membrane compartments is inhibited. Since membrane transport along microtubules is involved in secretion, endocytosis, and the positioning of organelles during interphase, we have explored whether the mitotic reorganization of membrane could involve a change in microtubule-based membrane t...

Abstract Microtubule targeting agents (MTAs) are indispensable medicines to treat a wide range of cancers. While evidence suggests that glioblastoma (GBM) is sensitive disruptions in microtubule (MT) functions; most MTAs do not reach the brain. To address this limitation, we developed brain-penetrant MTA, ST-401, kills patient-derived GBM culture at nanomolar concentrations, binds colchicine si...

Interphase microtubules are organized into a radial array with centrosome in the center. This organization is a subject of cellular regulation that can be driven by protein phosphorylation. Only few protein kinases that regulate microtubule array in interphase cells have been described. Ste20-like protein kinase LOSK (SLK) was identified as a microtubule and centrosome-associated protein. In th...

Stathmin is a microtubule-destabilizing protein ubiquitously expressed in vertebrates and highly expressed in many cancers. In several cell types, stathmin regulates the partitioning of tubulin between unassembled and polymer forms, but the mechanism responsible for partitioning has not been determined. We examined stathmin function in two cell systems: mouse embryonic fibroblasts (MEFs) isolat...

p53-binding protein 1 (53BP1) is well known for its roles in DNA damage signaling and DNA repair, especially for coordinating the two major DNA doublestrand break (DSB) repair pathways, i.e. it promotes non-homologous end-joining (NHEJ) repair but inhibits homologous recombination (HR) repair [1, 2]. Upon DSB induction in interphase cells, 53BP1 can be recruited to DSB sites via an ATM-mediated...

EB1 targets to polymerizing microtubule ends, where it is favorably positioned to regulate microtubule polymerization and confer molecular recognition of the microtubule end. In this study, we focus on two aspects of the EB1-microtubule interaction: regulation of microtubule dynamics by EB1 and the mechanism of EB1 association with microtubules. Immunodepletion of EB1 from cytostatic factor-arr...

Microtubule (MT)-dependent MT nucleation by γ-tubulin is required for interphase plant cells to establish a highly dynamic cortical MT network underneath the plasma membrane, which influences the deposition of cell wall materials and consequently governs patterns of directional cell expansion. Newly formed MTs either assume 40° angles or are parallel to the extant ones. To date, it has been eni...

Lecudina tuzetae is a parasitic protozoan (Gregarine, Apicomplexa) living in the intestine of a marine polychaete annelid, Nereis diversicolor. Using electron and fluorescence microscopy, we have characterized the dynamic changes in microtubule organization during the sexual phase of the life cycle. The gametocyst excreted from the host worm into seawater consists of two (one male and one femal...