Abstract:
:XMAP215/Dis1 proteins are conserved tubulin-binding TOG-domain proteins that regulate microtubule (MT) plus-end dynamics. Here we show that Alp14, a XMAP215 orthologue in fission yeast, Schizosaccharomyces pombe, has properties of a MT polymerase. In vivo, Alp14 localizes to growing MT plus ends in a manner independent of Mal3 (EB1). alp14-null mutants display short interphase MTs with twofold slower assembly rate and frequent pauses. Alp14 is a homodimer that binds a single tubulin dimer. In vitro, purified Alp14 molecules track growing MT plus ends and accelerate MT assembly threefold. TOG-domain mutants demonstrate that tubulin binding is critical for function and plus end localization. Overexpression of Alp14 or only its TOG domains causes complete MT loss in vivo, and high Alp14 concentration inhibits MT assembly in vitro. These inhibitory effects may arise from Alp14 sequestration of tubulin and effects on the MT. Our studies suggest that Alp14 regulates the polymerization state of tubulin by cycling between a tubulin dimer-bound cytoplasmic state and a MT polymerase state that promotes rapid MT assembly.
journal_name
Mol Biol Celljournal_title
Molecular biology of the cellauthors
Al-Bassam J,Kim H,Flor-Parra I,Lal N,Velji H,Chang Fdoi
10.1091/mbc.E12-03-0205subject
Has Abstractpub_date
2012-08-01 00:00:00pages
2878-90issue
15eissn
1059-1524issn
1939-4586pii
mbc.E12-03-0205journal_volume
23pub_type
杂志文章abstract::Lens fiber formation and morphogenesis requires a precise orchestration of cell- extracellular matrix (ECM) and cell-cell adhesive changes in order for a lens epithelial cell to adopt a lens fiber fate, morphology, and migratory ability. The cell-ECM interactions that mediate these processes are largely unknown, and h...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E12-09-0672
更新日期:2012-12-01 00:00:00
abstract::The protein composition of the plasma membrane is rapidly remodeled in response to changes in nutrient availability or cellular stress. This occurs, in part, through the selective ubiquitylation and endocytosis of plasma membrane proteins, which in the yeast Saccharomyces cerevisiae is mediated by the HECT E3 ubiquiti...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E19-08-0451
更新日期:2019-12-01 00:00:00
abstract::An in vitro transport assay, established with a modified Shiga toxin B subunit (STxB) as a marker, has proved to be useful for the study of transport from the early/recycling endosome (EE/RE) to the trans-Golgi network (TGN). Here, we modified this assay to test antibodies to all known soluble N-ethylmaleimide-sensiti...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e03-12-0876
更新日期:2004-09-01 00:00:00
abstract::In yeast, homologues of the synaptobrevin/VAMP family of v-SNAREs (Snc1 and Snc2) confer the docking and fusion of secretory vesicles at the cell surface. As no v-SNARE has been shown to confer endocytosis, we examined whether yeast lacking the SNC genes, or possessing a temperature-sensitive allele of SNC1 (SNC1(ala4...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.11.10.3629
更新日期:2000-10-01 00:00:00
abstract::The [URE3] and [PSI(+)] prions are infectious amyloid forms of Ure2p and Sup35p. Several chaperones influence prion propagation: Hsp104p overproduction destabilizes [PSI(+)], whereas [URE3] is sensitive to excess of Ssa1p or Ydj1p. Here, we show that overproduction of the chaperone, Sse1p, can efficiently cure [URE3]....
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e07-02-0128
更新日期:2007-06-01 00:00:00
abstract::GPI-linked hemagglutinin (GPI-HA) of influenza virus was thought to induce hemifusion without pore formation. Cells expressing either HA or GPI-HA were bound to red blood cells, and their fusion was compared by patch-clamp capacitance measurements and fluorescence microscopy. It is now shown that under more optimal fu...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.11.4.1143
更新日期:2000-04-01 00:00:00
abstract::Clathrin-mediated endocytosis regulates the internalization of many nutrient and signaling receptors. Clathrin and endocytic accessory proteins are recruited to receptors by specific adaptors. The adaptor Disabled-2 (Dab2) recruits its cargoes, including the low-density lipoprotein receptor (LDLR), and mediates endocy...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E11-09-0812
更新日期:2012-04-01 00:00:00
abstract::The complex cytopathology of mitochondrial diseases is usually attributed to insufficient ATP. AMP-activated protein kinase (AMPK) is a highly sensitive cellular energy sensor that is stimulated by ATP-depleting stresses. By antisense-inhibiting chaperonin 60 expression, we produced mitochondrially diseased strains wi...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e06-09-0881
更新日期:2007-05-01 00:00:00
abstract::B-type cyclins are rapidly degraded at the transition between metaphase and anaphase and their ubiquitin-mediated proteolysis is required for cells to exit mitosis. We used a novel enrichment to isolate new budding mutants that arrest the cell cycle in mitosis. Most of these mutants lie in the CDC16, CDC23, and CDC27 ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.8.10.1877
更新日期:1997-10-01 00:00:00
abstract::Cytokinesis requires the coordination of many cellular complexes, particularly those involved in the constriction and reconstruction of the plasma membrane in the cleavage furrow. We have investigated the regulation and function of vesicle transport and fusion during cytokinesis in budding yeast. By using time-lapse c...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e04-12-1090
更新日期:2005-05-01 00:00:00
abstract::Endoplasmic reticulum (ER) calcium homeostasis is disrupted in diverse pathologies, including neurodegeneration, cardiovascular diseases, and diabetes. Temporally defining calcium dysregulation during disease progression, however, has been challenging. Here we describe secreted ER calcium-monitoring proteins (SERCaMPs...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E14-06-1141
更新日期:2014-09-15 00:00:00
abstract::ER quality control (ERQC) prevents the exit of misfolded secretory and membrane proteins from the ER. A critical aspect of ERQC is a transcriptional response called the unfolded protein response (UPR), which up-regulates genes that enable cells to cope with misfolded, ER-retained proteins. In this study, we compare th...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e08-02-0140
更新日期:2009-02-01 00:00:00
abstract::Actin-based protrusions are important for signaling and migration during development and homeostasis. Defining how different tissues in vivo craft diverse protrusive behaviors using the same genomic toolkit of actin regulators is a current challenge. The actin elongation factors Diaphanous and Enabled both promote bar...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E14-05-0951
更新日期:2014-10-15 00:00:00
abstract::The exocyst is an evolutionarily conserved octameric protein complex that tethers post-Golgi secretory vesicles at the plasma membrane for exocytosis. To elucidate the mechanism of vesicle tethering, it is important to understand how the exocyst physically associates with the plasma membrane (PM). In this study, we re...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e07-05-0461
更新日期:2007-11-01 00:00:00
abstract::SINC, a new type III secreted protein of the avian and human pathogen Chlamydia psittaci, uniquely targets the nuclear envelope of C. psittaci-infected cells and uninfected neighboring cells. Digitonin-permeabilization studies of SINC-GFP-transfected HeLa cells indicate that SINC targets the inner nuclear membrane. SI...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E14-11-1530
更新日期:2015-05-15 00:00:00
abstract::The neonatal receptor for immunoglobulin G (IgG; FcRn) prevents IgG degradation by efficiently sorting IgG into recycling endosomes and away from lysosomes. When bound to IgG-opsonized antigen complexes, however, FcRn traffics cargo into lysosomes, where antigen processing can occur. Here we address the mechanism of s...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E13-04-0174
更新日期:2013-08-01 00:00:00
abstract::The cohesin complex (Mcd1p, Smc1p, Smc3p, and Scc3p) has multiple roles in chromosome architecture, such as promoting sister chromatid cohesion, chromosome condensation, DNA repair, and transcriptional regulation. The prevailing embrace model for sister chromatid cohesion posits that a single cohesin complex entraps b...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E15-06-0331
更新日期:2015-11-15 00:00:00
abstract::Transporting epithelial cells optimize their morphology for solute uptake by building an apical specialization: a dense array of microvilli that serves to increase membrane surface area. In the intestinal tract, individual cells build thousands of microvilli, which pack tightly to form the brush border. Recent studies...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E18-09-0558
更新日期:2019-01-01 00:00:00
abstract::Proteins establish and maintain a distinct intracellular localization by means of targeting, retention, and retrieval signals, ensuring most proteins reside predominantly in one cellular location. The enzymes involved in the maturation of lamin A present a challenge to this paradigm. Lamin A is first synthesized as a ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e08-07-0704
更新日期:2008-12-01 00:00:00
abstract::The microphthalmia-associated transcription factor (MITF) is required for terminal osteoclast differentiation and is a target for signaling pathways engaged by colony stimulating factor (CSF)-1 and receptor-activator of nuclear factor-kappaB ligand (RANKL). Work presented here demonstrates that MITF can shuttle from c...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e06-05-0470
更新日期:2006-09-01 00:00:00
abstract::Doing scientific research can be a challenging, but creative and rewarding career. However, the challenge of doing research is orders of magnitude more difficult for scientists lacking access to the necessary resources. Resource-scarce environments are quite common worldwide and are highly contingent on the financial ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E17-11-0645
更新日期:2018-06-01 00:00:00
abstract::When demembranated sperm nuclei are placed in a Xenopus egg extract, they become surrounded by a nuclear envelope and then swell to form morphologically typical pronuclei. Granules ranging from < 1.0 to approximately 3.0 microns in diameter appear within such nuclei. Bell et al. identified four nucleolar proteins in t...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.5.6.633
更新日期:1994-06-01 00:00:00
abstract::Substrates critical for transformation by pp60v-src remain unknown, as does the precise role of the src homology 2 (SH2) domain in this process. To continue exploring the role of the SH2 domain in pp60v-src-mediated transformation, site-directed mutagenesis was used to create mutant v-src alleles predicted to encode p...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.8.5.843
更新日期:1997-05-01 00:00:00
abstract::Growth of most eukaryotic cells requires directed transport along microtubules (MTs) that are nucleated at nuclear-associated microtubule organizing centers (MTOCs), such as the centrosome and the fungal spindle pole body (SPB). Herein, we show that the pathogenic fungus Ustilago maydis uses different MT nucleation si...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e02-08-0513
更新日期:2003-02-01 00:00:00
abstract::Actin nucleation factors function to organize, shape, and move membrane-bound organelles, yet they remain poorly defined in relation to disease. Galloway-Mowat syndrome (GMS) is an inherited disorder characterized by microcephaly and nephrosis resulting from mutations in the WDR73 gene. This core clinical phenotype ap...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E17-01-0022
更新日期:2017-09-15 00:00:00
abstract::Endocytic adaptor proteins facilitate cargo recruitment and clathrin-coated pit nucleation. The prototypical clathrin adaptor AP2 mediates cargo recruitment, maturation, and scission of the pit by binding cargo, clathrin, and accessory proteins, including the Eps-homology (EH) domain proteins Eps15 and intersectin. Ho...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E11-12-1007
更新日期:2012-08-01 00:00:00
abstract::Treacher Collins syndrome (TCS) is an autosomal dominant disorder of craniofacial development caused by mutations in the gene TCOF1. Its gene product, treacle, consists mainly of a central repeat domain, which shows it to be structurally related to the nucleolar phosphoprotein Nopp140. Treacle remains mostly uncharact...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.11.9.3061
更新日期:2000-09-01 00:00:00
abstract::Neural cell adhesion molecules (CAMs) are important players during neurogenesis and neurite outgrowth as well as axonal fasciculation and pathfinding. Some of these developmental processes entail the activation of cellular signaling cascades. Pharmacological and genetic evidence indicates that the neurite outgrowth-pr...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e03-05-0333
更新日期:2004-04-01 00:00:00
abstract::In endothelial cells specifically, cPLA2alpha translocates from the cytoplasm to the Golgi complex in response to cell confluence. Considering the link between confluence and cell-cell junction formation, and the emerging role of cPLA2alpha in intracellular trafficking, we tested whether Golgi-associated cPLA2alpha is...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e08-02-0210
更新日期:2009-10-01 00:00:00
abstract::In complex with FKBP12, the immunosuppressant rapamycin binds to and inhibits the yeast TOR1 and TOR2 proteins and the mammalian homologue mTOR/FRAP/RAFT1. The TOR proteins promote cell cycle progression in yeast and human cells by regulating translation and polarization of the actin cytoskeleton. A C-terminal domain ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.10.8.2531
更新日期:1999-08-01 00:00:00