Abstract:
:A novel selection scheme has been developed to isolate bloodstream forms of Trypanosoma brucei, which are defective in their ability to differentiate to the procyclic stage. Detailed characterization of one selected cell line (defective in differentiation clone 1 [DiD-1]) has demonstrated that these cells are indistinguishable from the wild-type population in terms of their morphology, cell cycle progression, and biochemical characteristics but are defective in their ability to initiate differentiation to the procyclic form. Although a small proportion of DiD-1 cells remain able to transform, deletion of the genes for glycophosphatidyl inositol-phospholipase C demonstrated that this enzyme was not responsible for this inefficient differentiation. However, the attenuated growth of the Delta-glycophosphatidyl inositol-phospholipase C DiD-1 cells in mice permitted the expression of stumpy characteristics in this previously monomorphic cell line, and concomitantly their ability to differentiate efficiently was restored. Our results indicate that monomorphic cells retain expression of a characteristic of the stumpy form essential for differentiation, and that this is reduced in the defective cells. This approach provides a new route to dissection of the cytological and molecular basis of life cycle progression in the African trypanosome.
journal_name
Mol Biol Celljournal_title
Molecular biology of the cellauthors
Tasker M,Wilson J,Sarkar M,Hendriks E,Matthews Kdoi
10.1091/mbc.11.5.1905keywords:
subject
Has Abstractpub_date
2000-05-01 00:00:00pages
1905-17issue
5eissn
1059-1524issn
1939-4586journal_volume
11pub_type
杂志文章abstract::Low molecular weight (LMW) GTP-binding proteins are hypothesized to play a role in the vectorial transport of intracellular vesicles. Mutational studies in yeast and subcellular localization in mammalian cells suggest that a family of LMW GTP-binding proteins, termed rab, target intracellular vesicles to their appropr...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.4.7.747
更新日期:1993-07-01 00:00:00
abstract::During a search for genes controlling conidial dormancy in Aspergillus fumigatus, two dehydrin-like genes, DprA and DprB, were identified. The deduced proteins had repeated stretches of 23 amino acids that contained a conserved dehydrin-like protein (DPR) motif. Disrupted DprAΔ mutants were hypersensitive to oxidative...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E10-11-0914
更新日期:2011-06-01 00:00:00
abstract::Vac8p is a vacuolar membrane protein that is required for efficient vacuole inheritance and fusion, cytosol-to-vacuole targeting, and sporulation. By analogy to other armadillo domain proteins, including beta-catenin and importin alpha, we hypothesize that Vac8p docks various factors at the vacuole membrane. Two-hybri...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.11.7.2445
更新日期:2000-07-01 00:00:00
abstract::Mammalian mitochondrial ribosomes contain two prokaryotic-like rRNAs, 12S and 16S, both encoded by mitochondrial DNA. As opposed to cytosolic ribosomes, however, these ribosomes are not thought to contain 5S rRNA. For this reason, it has been unclear whether 5S rRNA, which can be detected in mitochondrial preparations...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.9.9.2375
更新日期:1998-09-01 00:00:00
abstract::Clathrin and caveolins are known for their involvement in the internalization of numerous receptors. Here we show that in polarized epithelial Madin-Darby canine kidney cells, both the clathrin machinery and caveolins are involved in the endocytosis and delivery to the plasma membrane (PM) of the M1 muscarinic acetylc...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e06-07-0618
更新日期:2007-05-01 00:00:00
abstract::Guanine nucleotide exchange factors (GEFs) are the initiators of signaling by every regulatory GTPase, which in turn act to regulate a wide array of essential cellular processes. To date, each family of GTPases is activated by distinct families of GEFs. Bidirectional membrane trafficking is regulated by ADP-ribosylati...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E19-01-0073
更新日期:2019-07-15 00:00:00
abstract::We identified a direct interaction between the neuronal transmembrane protein calsyntenin-1 and the light chain of Kinesin-1 (KLC1). GST pulldowns demonstrated that two highly conserved segments in the cytoplasmic domain of calsyntenin-1 mediate binding to the tetratricopeptide repeats of KLC1. A complex containing ca...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e06-02-0112
更新日期:2006-08-01 00:00:00
abstract::In this essay I describe my personal journey from reductionist to systems cell biology and describe how this in turn led to a 3-year sea voyage to explore complex ocean communities. In describing this journey, I hope to convey some important principles that I gleaned along the way. I realized that cellular functions e...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E11-06-0571
更新日期:2012-07-01 00:00:00
abstract::Glucose is a master regulator of cell behavior in the yeast Saccharomyces cerevisiae. It acts as both a metabolic substrate and a potent regulator of intracellular signaling cascades. Glucose starvation induces the transient delocalization and then partial relocalization of clathrin adaptors at the trans-Golgi network...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E12-10-0750
更新日期:2013-03-01 00:00:00
abstract::Fission yeast rad22(+), a homologue of budding yeast RAD52, encodes a double-strand break repair component, which is dispensable for proliferation. We, however, have recently obtained a cell division cycle mutant with a temperature-sensitive allele of rad22(+), designated rad22-H6, which resulted from a point mutation...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.10.10.3331
更新日期:1999-10-01 00:00:00
abstract::How nuclear size is regulated is a fundamental cell-biological question with relevance to cancers, which often exhibit enlarged nuclei. We previously reported that conventional protein kinase C (cPKC) contributes to nuclear size reductions that occur during early Xenopus development. Here we report that PKC-mediated p...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E16-11-0786
更新日期:2017-05-15 00:00:00
abstract::In the phagocytic cell, NADPH oxidase (Nox2) system, cytoplasmic regulators (p47(phox), p67(phox), p40(phox), and Rac) translocate and associate with the membrane-spanning flavocytochrome b(558), leading to activation of superoxide production. We examined membrane targeting of phox proteins and explored conformational...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e06-08-0731
更新日期:2007-02-01 00:00:00
abstract::Astrocytes in neuron-free cultures typically lack processes, although they are highly process-bearing in vivo. We show that basic fibroblast growth factor (bFGF) induces cultured astrocytes to grow processes and that Ras family GTPases mediate these morphological changes. Activated alleles of rac1 and rhoA blocked and...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.10.5.1665
更新日期:1999-05-01 00:00:00
abstract::Rapid β2-integrin activation is indispensable for leukocyte adhesion and recruitment to sites of infection and is mediated by chemokine- or P-selectin glycoprotein ligand-1-induced inside-out signaling. Here we uncovered a novel pathway for rapid activation of integrin-dependent leukocyte adhesion, triggered by toll-l...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E14-04-0867
更新日期:2014-10-01 00:00:00
abstract::Whereas lysosome-related organelles (LRO) of specialized cells display both exocytic and endocytic features, lysosomes in nonspecialized cells can also acquire the property to fuse with the plasma membrane upon an acute rise in cytosolic calcium. Here, we characterize this unconventional secretory pathway in fibroblas...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E11-03-0193
更新日期:2011-06-15 00:00:00
abstract::Oncoprotein 18/stathmin (Op18) has been identified recently as a protein that destabilizes microtubules, but the mechanism of destabilization is currently controversial. Based on in vitro microtubule assembly assays, evidence has been presented supporting conflicting destabilization models of either tubulin sequestrat...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.10.1.105
更新日期:1999-01-01 00:00:00
abstract::The distinct levels of Rac activity differentially regulate the pattern of intrinsic cell migration. However, it remains unknown how Rac activity is modulated and how the level of Rac activity controls cell migratory behavior. Here we show that Slit-Robo GAP 1 (srGAP1) is a modulator of Rac activity in locomotive cell...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E13-04-0178
更新日期:2013-11-01 00:00:00
abstract::HURP is a spindle-associated protein that mediates Ran-GTP-dependent assembly of the bipolar spindle and promotes chromosome congression and interkinetochore tension during mitosis. We report here a biochemical mechanism of HURP regulation by Aurora A, a key mitotic kinase that controls the assembly and function of th...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e07-10-1088
更新日期:2008-05-01 00:00:00
abstract::Stress fibers were isolated from cultured human foreskin fibroblasts and bovine endothelial cells, and their contraction was demonstrated in vitro. Cells in culture dishes were first treated with a low-ionic-strength extraction solution and then further extracted using detergents. With gentle washes by pipetting, the ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.9.7.1919
更新日期:1998-07-01 00:00:00
abstract::The mannose 6-phosphate (Man-6-P) lysosomal targeting signal on acid hydrolases is synthesized by the sequential action of uridine 5'-diphosphate-N-acetylglucosamine: lysosomal enzyme N-acetylglucosamine-1-phosphotransferase (GlcNAc-1-phosphotransferase) and GlcNAc-1-phosphodiester alpha-N-acetylglucosaminidase ("unco...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e09-05-0398
更新日期:2009-10-01 00:00:00
abstract::Of the uncloned ODA genes required for outer dynein arm assembly in Chlamydomonas, ODA5 and ODA10 are of particular interest because they do not encode known subunits of the outer arm or the outer dynein arm-docking complex (ODA-DC), and because genetic studies suggest their products interact. Beginning with a tagged ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e03-11-0820
更新日期:2004-06-01 00:00:00
abstract::Cytochrome c release from mitochondria promotes apoptosome formation and caspase activation. The question as to whether mitochondrial permeabilization kills cells via a caspase-independent pathway when caspase activation is prevented is still open. Here we report that proneural cells of embryonic origin, when induced ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e07-09-0858
更新日期:2008-08-01 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::Formation and discharge of dense-core secretory vesicles depend on controlled rearrangement of the core proteins during their assembly and dispersal. The ciliate Tetrahymena thermophila offers a simple system in which the mechanisms may be studied. Here we show that most of the core consists of a set of polypeptides d...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.9.2.497
更新日期:1998-02-01 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 Lec35 gene product (Lec35p) is required for utilization of the mannose donor mannose-P-dolichol (MPD) in synthesis of both lipid-linked oligosaccharides (LLOs) and glycosylphosphatidylinositols, which are important for functions such as protein folding and membrane anchoring, respectively. The hamster Lec35 gene i...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.12.2.487
更新日期:2001-02-01 00:00:00
abstract::Stem cells are classically defined by their multipotent, long-term proliferation, and self-renewal capabilities. Here, we show that increased antioxidant capacity represents an additional functional characteristic of muscle-derived stem cells (MDSCs). Seeking to understand the superior regenerative capacity of MDSCs c...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e08-03-0274
更新日期:2009-01-01 00:00:00
abstract::Integrin-mediated adhesion induces several signaling pathways leading to regulation of gene transcription, control of cell cycle entry and survival from apoptosis. Here we investigate the involvement of the Janus kinase (JAK)/signal transducers and activators of transcription (STAT) pathway in integrin-mediated signal...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.10.10.3463
更新日期:1999-10-01 00:00:00
abstract::The septins are a family of homologous proteins that were originally identified in Saccharomyces cerevisiae, where they are associated with the "neck filaments" and are involved in cytokinesis and other aspects of the organization of the cell surface. We report here the identification of Sep1, a Drosophila melanogaste...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.6.12.1843
更新日期:1995-12-01 00:00:00
abstract::Chironomus tentans-repressor splicing factor (Ct-RSF) represses the activation of splicing by SR proteins in vitro. Ct-RSF colocalizes with the Ser-Arg-rich (SR) protein hrp45 in interchromatin granule clusters and coimmunoprecipitates with hrp45 in nuclear extracts. Ct-RSF and hrp45 can also interact directly in vitr...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e05-04-0339
更新日期:2006-01-01 00:00:00