Abstract:
:Rab2 immunolocalizes to pre-Golgi intermediates (vesicular-tubular clusters [VTCs]) that are the first site of segregation of anterograde- and retrograde-transported proteins and a major peripheral site for COPI recruitment. Our previous work showed that Rab2 Q65L (equivalent to Ras Q61L) inhibited endoplasmic reticulum (ER)-to-Golgi transport in vivo. In this study, the biochemical properties of Rab2 Q65L were analyzed. The mutant protein binds GDP and GTP and has a low GTP hydrolysis rate that suggests that Rab2 Q65L is predominantly in the GTP-bound-activated form. The purified protein arrests vesicular stomatitis virus glycoprotein transport from VTCs in an assay that reconstitutes ER-to-Golgi traffic. A quantitative binding assay was used to measure membrane binding of beta-COP when incubated with the mutant. Unlike Rab2 that stimulates recruitment, Rab2 Q65L showed a dose-dependent decrease in membrane-associated beta-COP when incubated with rapidly sedimenting membranes (ER, pre-Golgi, and Golgi). The mutant protein does not interfere with beta-COP binding but stimulates the release of slowly sedimenting vesicles containing Rab2, beta-COP, and p53/gp58 but lacking anterograde grade-directed cargo. To complement the biochemical results, we observed in a morphological assay that Rab2 Q65L caused vesiculation of VTCs that accumulated at 15 degrees C. These data suggest that the Rab2 protein plays a role in the low-temperature-sensitive step that regulates membrane flow from VTCs to the Golgi complex and back to the ER.
journal_name
Mol Biol Celljournal_title
Molecular biology of the cellauthors
Tisdale EJdoi
10.1091/mbc.10.6.1837keywords:
subject
Has Abstractpub_date
1999-06-01 00:00:00pages
1837-49issue
6eissn
1059-1524issn
1939-4586journal_volume
10pub_type
杂志文章abstract::Satellite cells (SCs), the resident adult stem cells of skeletal muscle, are required for tissue repair throughout life. While many signaling pathways are known to control SC self-renewal, less is known about the mechanisms underlying the spatiotemporal control of self-renewal during skeletal muscle repair. Here, we m...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E20-01-0078
更新日期:2020-07-21 00:00:00
abstract::Isu, the scaffold protein on which Fe-S clusters are built in the mitochondrial matrix, plays a central role in the biogenesis of Fe-S cluster proteins. We report that the reduction in the activity of several components of the cluster biogenesis system, including the specialized Hsp70 Ssq1, causes a 15-20-fold up-regu...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e08-06-0622
更新日期:2008-12-01 00:00:00
abstract::Starvation of Dictyostelium induces a developmental program in which cells form an aggregate that eventually differentiates into a multicellular structure. The aggregate formation is mediated by directional migration of individual cells that quickly transition to group migration in which cells align in a head-to-tail ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e09-03-0223
更新日期:2009-07-01 00:00:00
abstract::The transforming growth factor (TGF)-beta superfamily regulates cell proliferation, apoptosis, differentiation, migration, and development. Canonical TGFbeta signals are transduced to the nucleus via Smads in both major signaling branches, bone morphogenetic protein (BMP) or Activin/Nodal/TGFbeta. Smurf ubiquitin (Ub)...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e08-03-0325
更新日期:2009-07-01 00:00:00
abstract::The polysomal ribonuclease 1 (PMR1) mRNA endonuclease forms a selective complex with its translating substrate mRNAs where it is activated to initiate mRNA decay. Previous work showed tyrosine phosphorylation is required for PMR1 targeting to this polysome-bound complex, and it identified c-Src as the responsible kina...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e07-08-0774
更新日期:2008-02-01 00:00:00
abstract::Targeting of peroxisomal membrane proteins (PMPs) is a multistep process that requires not only recognition of PMPs in the cytosol but also their insertion into the peroxisomal membrane. As a consequence, targeting signals of PMPs (mPTS) are rather complex. A candidate protein for the PMP recognition event is Pex19p, ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e04-03-0188
更新日期:2004-07-01 00:00:00
abstract::Myo4p, a single-headed and nonprocessive class V myosin in budding yeast, transports >20 different mRNAs asymmetrically to the bud. Here, we determine the features of the Myo4p motor that are necessary for correct localization of ASH1 mRNA to the daughter cell, a process that also requires the adapter protein She3p an...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e08-08-0801
更新日期:2009-07-01 00:00:00
abstract::Ras signaling has been shown to play an important role in promoting cell survival in many different tissues. Here we show that upregulation of Ras activity in adult Drosophila neurons induces neuronal cell death, as evident from the phenotype of vacuolar peduncle (vap) mutants defective in the Drosophila RasGAP gene, ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e02-05-0297
更新日期:2003-01-01 00:00:00
abstract::Melanosomes are tissue-specific organelles within which melanin is synthesized and stored. The melanocyte-specific glycoprotein Pmel17 is enriched in the lumen of premelanosomes, where it associates with characteristic striations of unknown composition upon which melanin is deposited. However, Pmel17 is synthesized as...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.12.11.3451
更新日期:2001-11-01 00:00:00
abstract::We have shown previously that the transforming growth factor-beta (TGFbeta)-regulated Sma-Mad (Smad) protein 3 and Smad4 proteins transactivate the apolipoprotein C-III promoter in hepatic cells via a hormone response element that binds the nuclear receptor hepatocyte nuclear factor 4 (HNF-4). In the present study, we...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e02-07-0375
更新日期:2003-03-01 00:00:00
abstract::Five or more orthophosphates bound together by high-energy phosphoanhydride bonds are highly ubiquitous inorganic molecules called polyphosphate. Polyphosphate acts as a signaling molecule eliciting a number of responses in eukaryotic cells, but the mechanisms mediating these effects are poorly understood. Proliferati...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E18-10-0686
更新日期:2019-04-15 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::Yeast that naturally exhaust the glucose from their environment differentiate into three distinct cell types distinguishable by flow cytometry. Among these is a quiescent (Q) population, which is so named because of its uniform but readily reversed G1 arrest, its fortified cell walls, heat tolerance, and longevity. Da...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E13-05-0241
更新日期:2013-12-01 00:00:00
abstract::Although some of the principles of N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) function are well understood, remarkably little detail is known about sec1/munc18 (SM) protein function and its relationship to SNAREs. Popular models of SM protein function hold that these proteins promote or main...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e03-07-0535
更新日期:2004-01-01 00:00:00
abstract::The plant toxin ricin is transported retrogradely from the cell surface to the endoplasmic reticulum (ER) from where the enzymatically active part is retrotranslocated to the cytosol, presumably by the same mechanism as used by misfolded proteins. The ER degradation enhancing alpha-mannosidase I-like protein, EDEM, is...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e05-10-0961
更新日期:2006-04-01 00:00:00
abstract::Syntaxin 3 (Stx3), a SNARE protein located and functioning at the apical plasma membrane of epithelial cells, is required for epithelial polarity. A fraction of Stx3 is localized to late endosomes/lysosomes, although how it traffics there and its function in these organelles is unknown. Here we report that Stx3 underg...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E17-07-0461
更新日期:2017-10-15 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::Cell morphogenesis is a complex process that relies on a diverse array of proteins and pathways. We have identified a transglutaminase-like protein (Cyk3p) that functions in fission yeast morphogenesis. The phenotype of a cyk3 knockout strain indicates a primary role for Cyk3p in cytokinesis. Correspondingly, Cyk3p lo...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E11-07-0656
更新日期:2012-07-01 00:00:00
abstract::The endoplasmic reticulum (ER) of animal cells is a single, dynamic, and continuous membrane network of interconnected cisternae and tubules spread out throughout the cytosol in direct contact with the nuclear envelope. During mitosis, the nuclear envelope undergoes a major rearrangement, as it rapidly partitions its ...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e09-04-0327
更新日期:2009-08-01 00:00:00
abstract::The extracellular signal-regulated kinase (ERK) pathway is generally mitogenic, but, upon strong activation, it causes cell cycle arrest by a not-yet fully understood mechanism. In response to genotoxic stress, Chk1 hyperphosphorylates Cdc25A, a positive cell cycle regulator, and targets it for Skp1/Cullin1/F-box prot...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e09-01-0008
更新日期:2009-04-01 00:00:00
abstract::Cellular levels of the versatile second messenger cyclic (c)AMP are regulated by the antagonistic actions of the canonical G protein → adenylyl cyclase pathway that is initiated by G-protein-coupled receptors (GPCRs) and attenuated by phosphodiesterases (PDEs). Dysregulated cAMP signaling drives many diseases; for exa...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E18-10-0630
更新日期:2019-06-15 00:00:00
abstract::Previous studies have shown that in a given cell type, certain active genes associate with SC-35 domains, nuclear regions rich in RNA metabolic factors and excluded from heterochromatin. This organization is not seen for all active genes; therefore, it is important to determine whether and when this locus-specific org...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e03-06-0388
更新日期:2004-01-01 00:00:00
abstract::The cation-dependent mannose 6-phosphate receptor (CD-MPR) mediates the transport of lysosomal enzymes from the trans-Golgi network to endosomes. Evasion of lysosomal degradation of the CD-MPR requires reversible palmitoylation of a cysteine residue in its cytoplasmic tail. Because palmitoylation is reversible and ess...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.e03-11-0808
更新日期:2004-06-01 00:00:00
abstract::The Cdc42 guanosine triphosphatase (GTPase) plays a central role in polarity development in species ranging from yeast to humans. In budding yeast, a specific growth site is selected in the G1 phase. Rsr1, a Ras GTPase, interacts with Cdc42 and its associated proteins to promote polarized growth at the proper bud site...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E19-02-0106
更新日期:2019-09-15 00:00:00
abstract::Cell shape is regulated by cell adhesion and cytoskeletal and membrane dynamics. Cell shape, adhesion, and motility have a complex relationship and understanding them is important in understanding developmental patterning and embryogenesis. Here we show that the lipid kinase phosphatidylinositol 4-kinase III beta (PI4...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E19-11-0600
更新日期:2020-08-01 00:00:00
abstract::Axonemal dyneins are molecular motors that drive the beating of cilia and flagella. We report here the identification and partial cloning of seven unique axonemal dynein heavy chains from rat tracheal epithelial (RTE) cells. Combinations of axonemal-specific and degenerate primers to conserved regions around the catal...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.7.1.71
更新日期:1996-01-01 00:00:00
abstract::Cellular differentiation and lineage commitment are considered to be robust and irreversible processes during development. Recent work has shown that mouse and human fibroblasts can be reprogrammed to a pluripotent state with a combination of four transcription factors. We hypothesized that combinatorial expression of...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E11-10-0869
更新日期:2012-09-01 00:00:00
abstract::Activation of the epidermal growth factor receptor (EGFR) triggers multiple signaling pathways and rapid endocytosis of the epidermal growth factor (EGF)-receptor complexes. To directly visualize the compartmentalization of molecules involved in the major signaling cascade, activation of Ras GTPase, we constructed fus...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.01-11-0552
更新日期:2002-05-01 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::The Arp2/3 complex is the only known nucleator of branched F-actin filaments. Work in cultured cells has established a wide array of functions for this complex in controlling cell migration, shape, and adhesion. However, loss of Arp2/3 complex function in tissues has yielded cell type-specific phenotypes. Here we repo...
journal_title:Molecular biology of the cell
pub_type: 杂志文章
doi:10.1091/mbc.E14-10-1481
更新日期:2015-06-01 00:00:00