NDP Kinase 7 Is a Conserved Microtubule-Binding Protein Preferentially Expressed in Ciliated Cells

Secretion of misfolded tau, a microtubule-binding protein enriched in nerve cells, is linked to the progression of tau pathology. However, the molecular mechanisms underlying tau secretion are poorly understood. Recent work by Lee et al. [Biochemical J. (2021) 478: 1471–1484] demonstrated that the transmembrane domains of syntaxin6 and syntaxin8 could be exploited for tau release, setting a stage for testing a novel hypothesis that has profound implications in tauopathies (e.g. Alzheimer's disease, FTDP-17, and CBD/PSP) and other related neurodegenerative diseases. The present commentary highlights the importance and limitations of the study, and discusses opportunities and directions for future investigations.

Download Full-text

Inscuteable-dependent apical localization of the microtubule-binding protein Cornetto suggests a role in asymmetric cell division

Journal of Cell Science ◽

10.1242/jcs.114.20.3655 ◽

2001 ◽

Vol 114 (20) ◽

pp. 3655-3662 ◽

Cited By ~ 1

Author(s):

Silvia Bulgheresi ◽

Elke Kleiner ◽

Juergen A. Knoblich

Keyword(s):

Cell Fate ◽

Mitotic Spindle ◽

Binding Protein ◽

Protein Localization ◽

Apical Cell ◽

Coiled Coil ◽

Cell Cortex ◽

Dependent Manner ◽

Genetic Redundancy ◽

Microtubule Binding

Drosophila neuroblasts divide asymmetrically along the apical-basal axis. The Inscuteable protein localizes to the apical cell cortex in neuroblasts from interphase to metaphase, but disappears in anaphase. Inscuteable is required for correct spindle orientation and for asymmetric localization of cell fate determinants to the opposite (basal) cell cortex. Here, we show that Inscuteable also directs asymmetric protein localization to the apical cell cortex during later stages of mitosis. In a two-hybrid screen for Inscuteable-binding proteins, we have identified the coiled-coil protein Cornetto, which shows a highly unusual subcellular distribution in neuroblasts. Although the protein is uniformly distributed in the cytoplasm during metaphase, it concentrates apically in anaphase and forms an apical crescent during telophase in an inscuteable-dependent manner. Upon overexpression, Cornetto localizes to astral microtubules and microtubule spin-down experiments demonstrate that Cornetto is a microtubule-binding protein. After disruption of the actin cytoskeleton, Cornetto localizes with microtubules throughout the cell cycle and decorates the mitotic spindle during metaphase. Our results reveal a novel pattern of asymmetric protein localization in Drosophila neuroblasts and are consistent with a function of Cornetto in anchoring the mitotic spindle during late phases of mitosis, even though our cornetto mutant analysis suggests that this function might be obscured by genetic redundancy.

Download Full-text

Metastasis-associated microtentacles are induced in detached and circulating breast tumor cells by expression of the microtubule-binding protein, Tau.

10.1158/0008-5472.sabcs-55 ◽

2009 ◽

Cited By ~ 1

Author(s):

M Matrone ◽

R Whipple ◽

E Balzer ◽

E Cho ◽

J Yoon ◽

...

Keyword(s):

Tumor Cells ◽

Breast Tumor ◽

Binding Protein ◽

Microtubule Binding ◽

Breast Tumor Cells ◽

Protein Tau

Download Full-text

CHARACTERISATION OF THE TRANSLATIONALLY REGULATED, MICROTUBULE BINDING PROTEIN P23

Biochemical Society Transactions ◽

10.1042/bst024516sa ◽

1996 ◽

Vol 24 (4) ◽

pp. 516S-516S

Author(s):

Yannick Gachet ◽

Melanie Lee ◽

Birgit Sawitzki ◽

Terry Poulton ◽

Ulrich-Axel Bommer

Keyword(s):

Binding Protein ◽

Microtubule Binding

Download Full-text

Bim1p/Yeb1p Mediates the Kar9p-dependent Cortical Attachment of Cytoplasmic Microtubules

Molecular Biology of the Cell ◽

10.1091/mbc.11.9.2949 ◽

2000 ◽

Vol 11 (9) ◽

pp. 2949-2959 ◽

Cited By ~ 102

Author(s):

Rita K. Miller ◽

Soo-Chen Cheng ◽

Mark D. Rose

Keyword(s):

Fluorescent Protein ◽

Binding Protein ◽

Spindle Pole Body ◽

Attachment Site ◽

Spindle Pole ◽

Cell Cortex ◽

Microtubule Binding ◽

Pole Body ◽

Cytoplasmic Microtubules ◽

Two Hybrid

In Saccharomyces cerevisiae, positioning of the mitotic spindle depends on the interaction of cytoplasmic microtubules with the cell cortex. In this process, cortical Kar9p in the bud acts as a link between the actin and microtubule cytoskeletons. To identify Kar9p-interacting proteins, a two-hybrid screen was conducted with the use of full-length Kar9p as bait, and three genes were identified: BIM1, STU2, andKAR9 itself. STU2 encodes a component of the spindle pole body. Bim1p is the yeast homologue of the human microtubule-binding protein EB1, which is a binding partner to the adenomatous polyposis coli protein involved in colon cancer. Eighty-nine amino acids within the third quarter of Bim1p was sufficient to confer interaction with Kar9p. The two-hybrid interactions were confirmed with the use of coimmunoprecipitation experiments. Genetic analysis placed Bim1p in the Kar9p pathway for nuclear migration. Bim1p was not required for Kar9p's cortical or spindle pole body localization. However, deletion ofBIM1 eliminated Kar9p localization along cytoplasmic microtubules. Furthermore, in the bim1 mutants, the cytoplasmic microtubules no longer intersected the cortical dot of Green Fluorescent Protein–Kar9p. These experiments demonstrate that the interaction of cytoplasmic microtubules with the Kar9p cortical attachment site requires the microtubule-binding protein Bim1p.

Download Full-text