Abstract：
:The oligosaccharyltransferase (OST) complex catalyses the N-glycosylation of polypeptides entering the endoplasmic reticulum, a process essential for the productive folding and trafficking of many secretory and membrane proteins. In eukaryotes, the OST typically comprises a homologous catalytic STT3 subunit complexed with several additional components that are usually conserved, and that often function to modulate N-glycosylation efficiency. By these criteria, the status of keratinocyte-associated protein 2 (KCP2) was unclear: it was found to co-purify with the canine OST suggesting it is part of the complex but, unlike most other subunits, no potential homologues are apparent in Saccharomyces cerevisiae. In this study we have characterised human KCP2 and show that the predominant species results from an alternative initiation of translation to form an integral membrane protein with three transmembrane spans. KCP2 localises to the endoplasmic reticulum, consistent with a role in protein biosynthesis, and has a functional KKxx retrieval signal at its cytosolic C-terminus. Native gel analysis suggests that the majority of KCP2 assembles into a distinct ~500 kDa complex that also contains several bona fide OST subunits, most notably the catalytic STT3A isoform. Co-immunoprecipitation studies confirmed a robust and specific physical interaction between KCP2 and STT3A, and revealed weaker associations with both STT3B and OST48. Taken together, these data strongly support the proposal that KCP2 is a newly identified subunit of the N-glycosylation machinery present in a subset of eukaryotes.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
Roboti P,High Sdoi
10.1242/jcs.094599subject
Has Abstractpub_date
2012-01-01 00:00:00pages
220-32issue
Pt 1eissn
0021-9533issn
1477-9137pii
jcs.094599journal_volume
125pub_type
杂志文章abstract：:Polarization of early embryos provides a foundation to execute essential patterning and morphogenetic events. In Caenorhabditis elegans, cell contacts polarize early embryos along their radial axis by excluding the cortical polarity protein PAR-6 from sites of cell contact, thereby restricting PAR-6 to contact-free ce...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.124594
更新日期：2013-04-01 00:00:00
abstract：:After DNA replication, cells condense their chromosomes in order to segregate them during mitosis. The condensation process as well as subsequent segregation requires phosphorylation of histone H3 at serine 10. Histone H3 phosphorylation initiates during G2 in pericentric foci prior to H3 phosphorylation in the chromo...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2001-02-01 00:00:00
abstract：:Patients with myotonic dystrophy type 1 exhibit a diversity of symptoms that affect many different organs. Among these are cognitive dysfunctions, the origin of which has remained elusive, partly because of the difficulty in accessing neural cells. Here, we have taken advantage of pluripotent stem cell lines derived f...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.116285
更新日期：2013-04-15 00:00:00
abstract：:Using finite aperture theory we have shown that localized very dark areas in the interference reflection images of Dictyostelium discoideum amoebae are due to the close intracellular approach of vesicles and tubular elements of the contractile vacuole system to the plasma membrane adjacent to the substratum. Vesicles ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1982-04-01 00:00:00
abstract：:Centriolar satellites are membrane-less structures that localize and move around the centrosome and cilium complex in a microtubule-dependent manner. They play important roles in centrosome- and cilium-related processes, including protein trafficking to the centrosome and cilium complex, and ciliogenesis, and they are...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.196832
更新日期：2017-04-15 00:00:00
abstract：:Integral membrane and secretory proteins which fail to fold productively are retained in the endoplasmic reticulum and targeted for degradation by cytoplasmic proteasomes. Genetic and biochemical analyses suggest that substrates of this pathway must be dislocated across the membrane of the endoplasmic reticulum (ER) b...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2002-07-15 00:00:00
abstract：:The regulation and function of the crucial cell cycle regulator cyclin E (CycE) remains elusive. Unlike other cyclins, CycE can be uniquely controlled by mitochondrial energetics, the exact mechanism being unclear. Using mammalian cells (in vitro) and Drosophila (in vivo) model systems in parallel, we show that CycE c...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.172429
更新日期：2015-11-15 00:00:00
abstract：:The path that RNA takes through nuclear pores was mapped using two high-resolution techniques. Unexpectedly, no RNA in HL60 cells was detected by immunogold labelling in the central axis of the pore complex on its way to the transporter at the nuclear membrane; instead, it was distributed around the sides, apparently ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2000-01-01 00:00:00
abstract：:The DNA content of isolated micronuclei, differentiating macronuclei (macronuclear Anlagen), and adult macronuclei of Loxodes magnus was measured cytofluorimetrically in preparations stained with a Schiff-type reagent, auramine-SO2, following hydrochloric acid hydrolysis. The DNA content of the youngest macronuclear A...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1980-08-01 00:00:00
abstract：:Desmocollin 3 (Dsc3) is a transmembrane glycoprotein that belongs to the cadherin family of cell adhesion receptors. Together with desmoglein(s), it forms the transmembrane core of desmosomes, a multiprotein complex involved in cell adhesion, organization of the cytoskeleton, cell sorting and cell signaling. Previous ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.02769
更新日期：2006-02-01 00:00:00
abstract：:During early stages of meiotic prophase I the nucleus undergoes considerable reorganization, including the clustering of telomeres, the release of contacts between chromosomes and the nuclear membrane, the reorganization of the nucleolus, and chromatin remodeling. Using a light squashing technique for the analysis of ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.03155
更新日期：2006-09-15 00:00:00
abstract：:Circadian rhythms regulate a wide variety of physiological and metabolic processes. The clock machinery comprises complex transcriptional-translational feedback loops that, through the action of specific transcription factors, modulate the expression of as many as 10% of cellular transcripts. This marked change in gen...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
doi：10.1242/jcs.051649
更新日期：2010-11-15 00:00:00
abstract：:Although telomere formation occurs through a different mechanism in Drosophila compared with other organisms, telomere associations result from mutations in homologous genes, indicating the involvement of similar pathways in chromosome end protection. We report here that mutations of the Drosophila melanogaster gene C...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.035097
更新日期：2009-03-15 00:00:00
abstract：:Integrins mediate cell adhesion and signal transduction at focal adhesions. Here we investigate the roles of integrin beta subunits in the regulation of actin cytoskeletal structure and the activities of Rho and Rac. The overexpression of beta3 integrin in Chinese hamster ovary cells enhances Rho activity and stress f...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2002-05-15 00:00:00
abstract：:The Na(+)/H(+) exchanger NHE1 is involved in intracellular pH homeostasis and cell volume regulation and accumulates with actin in the lamellipodia of fibroblasts. In order to determine the role of NHE1 following epithelial transformation and the acquisition of motile and invasive properties, we studied NHE1 expressio...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2000-10-01 00:00:00
abstract：:Vesicle-vesicle fusion initiated in cell cytoplasm by high Ca(2+) can rapidly erect large membrane boundaries. These might be used as a 'patch' for resealing plasma membrane disruptions. Three central predictions of this 'patch' hypothesis are here established in sea urchin eggs. First, we show that surface markers fo...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2000-06-01 00:00:00
abstract：:When human cells enter S-phase, overlapping differential inhibitory mechanisms downregulate the replication licensing factors ORC1, CDC6 and Cdt1. Such regulation prevents re-replication so that deregulation of any individual factor alone would not be expected to induce overt re-replication. However, this has been cha...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.041889
更新日期：2009-04-15 00:00:00
abstract：:A fundamental aspect in the morphogenesis of a polarized epithelium is the formation of structurally and functionally distinct apical and basal-lateral domains of the plasma membrane. The formation of these membrane domains involves the accumulation of domain-specific proteins and removal of incorrectly localized prot...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1990-01-01 00:00:00
abstract：:Nuclear lamin A and C alleles that are linked to three distinct human diseases have been expressed both in HeLa cells and in fibroblasts derived from Lmna null mice. Point mutations that cause dilated cardiomyopathy (L85R and N195K) and autosomal dominant Emery-Dreifuss muscular dystrophy (L530P) modify the assembly p...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2001-12-01 00:00:00
abstract：:Pollen diffusates, known to be important in pollen-stigma interactions controlling interspecific incompatibility between Populus deltoides and Populus alba, have been partly characterized and shown to contain more than 20 protein bands by polyacrylamide gel electrophoresis, at least 4 of these being glycoproteins. Sev...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1980-08-01 00:00:00
abstract：:Axin and conductin (also known as axin2) are structurally related inhibitors of Wnt/β-catenin signalling that promote degradation of β-catenin. Whereas axin is constitutively expressed, conductin is a Wnt target gene implicated in Wnt negative-feedback regulation. Here, we show that axin and conductin differ in their ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.159145
更新日期：2015-01-01 00:00:00
abstract：:Although loss of cell-cell adhesion and gain of invasive properties play a crucial role in the malignant progression of epithelial tumours, the molecular signals that trigger these processes have not been fully elucidated. In light of the well-established relationship between chronic inflammation and cancer, we hypoth...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.02467
更新日期：2005-08-01 00:00:00
abstract：:The marginal band microtubules of isolated Xenopus erythrocyte cytoskeletons possess the stability properties of non-steady-state microtubules. They are unperturbed by low temperatures, a variety of microtubule inhibitors, hypotonic treatment and the direct action of calcium. These microtubules can be rapidly depolyme...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1985-11-01 00:00:00
abstract：:The mammalian lens consists of an aged core of quiescent cells enveloped by a layer of synthetically active cells. Abundant gap junctions within and between these cell populations ensure that the lens functions as an electrical syncytium and facilitates the exchange of small molecules between surface and core cells. I...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.00738
更新日期：2003-10-15 00:00:00
abstract：:Concomitant expression of mutant p53 and oncogenic Ras, leading to cellular transformation, is well documented. However, the mechanisms by which the various mutant p53 categories cooperate with Ras remain largely obscure. From this study we suggest that different mutant p53 categories cooperate with H-Ras in different...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.099663
更新日期：2012-07-01 00:00:00
abstract：:Actin-filament disassembly is crucial for actin-based motility, to control filament network architecture and to regenerate subunits for assembly. Here, we examined the roles of three actin cytoskeletal proteins, coronin, cofilin and Aip1, which have been suggested to combine in various ways to control actin dynamics b...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.065698
更新日期：2010-04-15 00:00:00
abstract：:Macroautophagy is morphologically characterized by autophagosome formation. Autophagosomes are double-membraned vesicles that sequester cytoplasmic components for further degradation in the lysosome. Basal autophagy is paramount for intracellular quality control in post-mitotic cells but, surprisingly, the number of a...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.188060
更新日期：2017-01-01 00:00:00
abstract：:Previously we have shown that the Saccharomyces cerevisiae CCZ1 (YBR131w) gene encodes a protein involved in protein trafficking. Deletion of this gene leads to fragmentation of the vacuole typical of the class B vps mutants. Genetic and biochemical data indicated that Ccz1p is required for fusion of various transport...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2001-09-01 00:00:00
abstract：:Heat shock transcription factor 1 (HSF1) regulates the expression of a wide array of genes, controls the expression of heat shock proteins (HSPs) as well as cell growth. Although acute depletion of HSF1 induces cellular senescence, the underlying mechanisms are poorly understood. Here, we report that HSF1 depletion-in...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.210724
更新日期：2018-05-08 00:00:00
abstract：:Agrin, a 200 kDa extracellular matrix protein, participates in the maturation of the postsynaptic target at the neuromuscular junction. Although agrin has also been detected in central neurons, little is known about its role in the formation of their synapses. In the present study, the pattern of expression, localizat...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1999-12-01 00:00:00
