Abstract:
:Autocrine motility factor receptor (AMF-R) is a cell surface receptor that is also localized to a smooth subdomain of the endoplasmic reticulum, the AMF-R tubule. By postembedding immunoelectron microscopy, AMF-R concentrates within smooth plasmalemmal vesicles or caveolae in both NIH-3T3 fibroblasts and HeLa cells. By confocal microscopy, cell surface AMF-R labeled by the addition of anti-AMF-R antibody to viable cells at 4 degreesC exhibits partial colocalization with caveolin, confirming the localization of cell surface AMF-R to caveolae. Labeling of cell surface AMF-R by either anti-AMF-R antibody or biotinylated AMF (bAMF) exhibits extensive colocalization and after a pulse of 1-2 h at 37 degreesC, bAMF accumulates in densely labeled perinuclear structures as well as fainter tubular structures that colocalize with AMF-R tubules. After a subsequent 2- to 4-h chase, bAMF is localized predominantly to AMF-R tubules. Cytoplasmic acidification, blocking clathrin-mediated endocytosis, results in the essentially exclusive distribution of internalized bAMF to AMF-R tubules. By confocal microscopy, the tubular structures labeled by internalized bAMF show complete colocalization with AMF-R tubules. bAMF internalized in the presence of a 10-fold excess of unlabeled AMF labels perinuclear punctate structures, which are therefore the product of fluid phase endocytosis, but does not label AMF-R tubules, demonstrating that bAMF targeting to AMF-R tubules occurs via a receptor-mediated pathway. By electron microscopy, bAMF internalized for 10 min is located to cell surface caveolae and after 30 min is present within smooth and rough endoplasmic reticulum tubules. AMF-R is therefore internalized via a receptor-mediated clathrin-independent pathway to smooth ER. The steady state localization of AMF-R to caveolae implicates these cell surface invaginations in AMF-R endocytosis.
journal_name
Mol Biol Celljournal_title
Molecular biology of the cellauthors
Benlimame N,Le PU,Nabi IRdoi
10.1091/mbc.9.7.1773subject
Has Abstractpub_date
1998-07-01 00:00:00pages
1773-86issue
7eissn
1059-1524issn
1939-4586journal_volume
9pub_type
杂志文章abstract::To test the "traction fiber" model for metaphase positioning of bivalents during meiosis, kinetochore fibers of maloriented bivalents, induced during recovery from cold arrest, were analyzed with a liquid crystal polarizing microscope. The measured birefringence retardation of kinetochore fibers is proportional to the...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e04-06-0524
更新日期:2004-12-01 00:00:00
abstract::In this study, we examined the subcellular distribution and functions of LIMK1 in developing neurons. Confocal microscopy, subcellular fractionation, and expression of several epitope-tagged LIMK1 constructs revealed that LIMK1 is enriched in the Golgi apparatus and growth cones, with the LIM domain required for Golgi...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e03-05-0328
更新日期:2004-07-01 00:00:00
abstract::Epithelial tissues are protective barriers that display a remarkable ability to repair wounds. Wound repair is often associated with an accumulation of actin and nonmuscle myosin II around the wound, forming a purse string. The role of actomyosin networks in generating mechanical force during wound repair is not well ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E13-05-0228
更新日期:2013-10-01 00:00:00
abstract::MPM-2 antigens, a discrete set of phosphoproteins that contain similar phosphoepitopes recognized by the monoclonal antibody MPM-2, are phosphorylated during M-phase induction. Our previous studies suggested that certain MPM-2 antigens are involved in the appearance of maturation-promoting factor (MPF) activity. Becau...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.5.2.135
更新日期:1994-02-01 00:00:00
abstract::The fission yeast Mcs6-Mcs2-Pmh1 complex, homologous to metazoan Cdk7-cyclin H-Mat1, has dual functions in cell division and transcription: as a partially redundant cyclin-dependent kinase (CDK)-activating kinase (CAK) that phosphorylates the major cell cycle CDK, Cdc2, on Thr-167; and as the RNA polymerase (Pol) II c...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e04-11-0982
更新日期:2005-06-01 00:00:00
abstract::Molecular chaperones play key roles during growth, development, and stress survival. The ability to induce chaperone expression enables cells to cope with the accumulation of nonnative proteins under stress and complete developmental processes with an increased requirement for chaperone assistance. Here we generate an...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E14-02-0742
更新日期:2014-08-01 00:00:00
abstract::Both sporadic and familial Alzheimer's disease (AD) patients exhibit increased chromosome aneuploidy, particularly trisomy 21, in neurons and other cells. Significantly, trisomy 21/Down syndrome patients develop early onset AD pathology. We investigated the mechanism underlying mosaic chromosome aneuploidy in AD and r...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e09-10-0850
更新日期:2010-02-15 00:00:00
abstract::Long-distance transport is crucial for polar-growing cells, such as neurons and fungal hyphae. Kinesins and myosins participate in this process, but their functional interplay is poorly understood. Here, we investigate the role of kinesin motors in hyphal growth of the plant pathogen Ustilago maydis. Although the micr...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e05-04-0272
更新日期:2005-11-01 00:00:00
abstract::McKusick-Kaufman syndrome (MKKS) is a recessively inherited human genetic disease characterized by several developmental anomalies. Mutations in the MKKS gene also cause Bardet-Biedl syndrome (BBS), a genetically heterogeneous disorder with pleiotropic symptoms. However, little is known about how MKKS mutations lead t...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e07-07-0631
更新日期:2008-03-01 00:00:00
abstract::Colony-stimulating factor-1 (CSF-1) induces expression of immediate early gene, such as c-myc and c-fos and delayed early genes such as D-type cyclins (D1 and D2), whose products play essential roles in the G1 to S phase transition of the cell cycle. Little is known, however, about the cytoplasmic signal transduction ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.11.11.3835
更新日期:2000-11-01 00:00:00
abstract::We conducted a genetic screen for mutations in myospheroid, the gene encoding the Drosophila betaPS integrin subunit, and identified point mutants in all of the structural domains of the protein. Surprisingly, we find that mutations in very strongly conserved residues will often allow sufficient integrin function to s...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e04-02-0085
更新日期:2004-08-01 00:00:00
abstract::Nuclear FGFR1 acts as a developmental gene regulator in cooperation with FGF-2, RSK1, and CREB-binding protein (CBP). FRAP analysis revealed three nuclear FGFR1 populations: i) a fast mobile, ii) a slower mobile population reflecting chromatin-bound FGFR1, and iii) an immobile FGFR1 population associated with the nucl...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e08-06-0600
更新日期:2009-05-01 00:00:00
abstract::The cell nucleus must continually resist and respond to intercellular and intracellular mechanical forces to transduce mechanical signals and maintain proper genome organization and expression. Altered nuclear mechanics is associated with many human diseases, including heart disease, progeria, and cancer. Chromatin an...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E16-09-0653
更新日期:2017-07-07 00:00:00
abstract::Intracellular free calcium ([Ca2+]i) has been proposed to play an important part in the regulation of the cell cycle. Although a number of studies have shown that stimulation of quiescent cells with growth factors causes an immediate rise in [Ca2+]i (Rabinovitch et al., 1986; Vincentini and Villereal, 1986; Hesketh et...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.4.3.293
更新日期:1993-03-01 00:00:00
abstract::Osteosarcoma is the most frequent primary tumor of bone and is characterized by its high tendency to metastasize in lungs. Although treatment in cases of early diagnosis results in a 5-yr survival rate of nearly 60%, the prognosis for patients with secondary lesions at diagnosis is poor, and their 5-yr survival rate r...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E18-08-0545
更新日期:2019-03-21 00:00:00
abstract::Chromatin and nuclear pore complexes (NPCs) undergo dramatic changes during mitosis, which in vertebrates and Aspergillus nidulans involves movement of Nup2 from NPCs to the chromatin region to fulfill unknown functions. This transition is shown to require the Cdk1 mitotic kinase and be promoted prematurely by ectopic...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E14-09-1359
更新日期:2015-02-15 00:00:00
abstract::Cell morphogenesis depends on polarized exocytosis. One widely held model posits that long-range transport and exocyst-dependent tethering of exocytic vesicles at the plasma membrane sequentially drive this process. Here, we describe that disruption of either actin-based long-range transport and microtubules or the ex...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E10-08-0720
更新日期:2011-01-01 00:00:00
abstract::To further elucidate the functions of actin in budding yeast and to relate actin structure to specific roles and interactions in vivo, we determined the phenotypes caused by 13 charged-to-alanine mutations isolated previously in the single Saccharomyces cerevisiae actin gene. Defects in actin organization, morphogenes...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.4.12.1277
更新日期:1993-12-01 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::Lipid droplets (LDs) form from the endoplasmic reticulum (ER) and grow in size by obtaining triacylglycerols (TG). Triacylglycerol hydrolase (TGH), a lipase residing in the ER, is involved in the mobilization of TG stored in LDs for the secretion of very-low-density lipoproteins. In this study, we investigated TGH-med...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e09-05-0364
更新日期:2010-06-15 00:00:00
abstract::Heterotrimeric G proteins are components of principal signaling pathways in eukaryotes. In higher organisms, alpha subunits of G proteins have been divided into four families, Gi, Gs, Gq, and G12. We previously identified a G alpha i homologue gna-1 in the filamentous fungus Neurospora crassa. Now we report that delet...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.7.8.1283
更新日期:1996-08-01 00:00:00
abstract::The skin's epidermis is a multilayered epithelial tissue and the first line of defense against mechanical stress. Its barrier function depends on an integrated assembly and reorganization of cell-matrix and cell-cell junctions in the basal layer and on different intercellular junctions in suprabasal layers. However, h...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E17-06-0387
更新日期:2018-09-15 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::In pancreatic β-cells, glutamate dehydrogenase (GDH) modulates insulin secretion, although its function regarding specific secretagogues is unclear. This study investigated the role of GDH using a β-cell-specific GDH knockout mouse model, called βGlud1(-/-). The absence of GDH in islets isolated from βGlud1(-/-) mice ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E11-08-0676
更新日期:2012-10-01 00:00:00
abstract::Although evasion of apoptosis is thought to be required for the development of cancer, it is unclear which cell death pathways are evaded. We previously identified a novel epithelial cell death pathway that works in normal cells but is inactivated in tumor cells, implying that it may be targeted during tumor developme...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e04-10-0906
更新日期:2005-03-01 00:00:00
abstract::Myosin- and Rab-interacting protein (MyRIP), which belongs to the protein kinase A (PKA)-anchoring family, is implicated in hormone secretion. However, its mechanism of action is not fully elucidated. Here we investigate the role of MyRIP in myosin Va (MyoVa)-dependent secretory granule (SG) transport and secretion in...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E12-05-0369
更新日期:2012-11-01 00:00:00
abstract::In addition to their well-known role in microtubule organization, centrosomes function as signaling platforms and regulate cell cycle events. An important example of such a function is the spindle position checkpoint (SPOC) of budding yeast. SPOC is a surveillance mechanism that ensures alignment of the mitotic spindl...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E14-04-0890
更新日期:2014-07-15 00:00:00
abstract::Fibrillins constitute the major backbone of multifunctional microfibrils in elastic and nonelastic extracellular matrices. Proper assembly mechanisms are central to the formation and function of these microfibrils, and their properties are often compromised in pathological circumstances such as in Marfan syndrome and ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e08-08-0830
更新日期:2009-02-01 00:00:00
abstract::CWH41, a gene involved in the assembly of cell wall beta-1,6-glucan, has recently been shown to be the structural gene for Saccharomyces cerevisiae glucosidase I that is responsible for initiating the trimming of terminal alpha-1,2-glucose residue in the N-glycan processing pathway. To distinguish between a direct or ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.9.10.2729
更新日期:1998-10-01 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