• The presence of the nuclear membrane that sequesters the cellular DNA is the defining feature of eukaryotic cells. (wikipedia.org)
  • The nuclear membrane, therefore, separates the nuclear processes of DNA replication and RNA transcription from the cytoplasmic process of protein production. (wikipedia.org)
  • The presence of several million pore complexes in the oocyte nuclear membrane and the fact that they appeared to admit many different molecules (insulin, bovine serum albumin, gold nanoparticles) led to the view that the pores are open channels and nuclear proteins freely enter the nucleus through the pore and must accumulate by binding to DNA or some other nuclear component. (wikipedia.org)
  • In eukaryotic cells the genetic material is surrounded by a membrane system called the nuclear envelope (NE). (brookes.ac.uk)
  • The results highlight the importance of mid-SUNs as functional components of the ER and outer nuclear membrane. (brookes.ac.uk)
  • Despite its emerging role as a key structural and signaling platform, the plant NE remains one of the least understood membrane systems. (brookes.ac.uk)
  • Better understanding of this membrane system involves understanding its physical connections and its signaling and transport functions. (brookes.ac.uk)
  • Retroviral particles must bind specifically to their target cells, cross the plasma membrane, reverse-transcribe their RNA genome, while uncoating the cores, find their way to the nuclear membrane and penetrate into the nucleus to finally dock and integrate into the cellular genome. (biomedcentral.com)
  • A nuclear localization signal or sequence (NLS) is an amino acid sequence that 'tags' a protein for import into the cell nucleus by nuclear transport. (wikipedia.org)
  • An NLS has the opposite function of a nuclear export signal (NES), which targets proteins out of the nucleus. (wikipedia.org)
  • The first direct experimental examination of the ability of nuclear proteins to accumulate in the nucleus was carried out by John Gurdon when he showed that purified nuclear proteins accumulate in the nucleus of frog (Xenopus) oocytes after being micro-injected into the cytoplasm. (wikipedia.org)
  • During the long journey from the cell surface to the nucleus, retroviruses will face multiple obstacles, since in addition to finding a path through the cytoplasm to the nucleus they have to cross two main barriers, the plasma and nuclear membranes, whilst at the same time avoiding or counteracting cellular defences that can interfere with many of these steps. (biomedcentral.com)
  • The major structural differences between the two are that the two basic amino acid clusters in bipartite NLSs are separated by a relatively short spacer sequence (hence bipartite - 2 parts), while monopartite NLSs are not. (wikipedia.org)
  • Different nuclear localized proteins may share the same NLS. (wikipedia.org)
  • A signal that appears to be specific for the massively produced and transported ribosomal proteins, seems to come with a specialized set of importin β-like nuclear import receptors. (wikipedia.org)
  • In fact, only a small percentage of cellular (non-viral) nuclear proteins contained a sequence similar to the SV40 NLS. (wikipedia.org)
  • Much has been learned regarding nuclear entry, but the cellular proteins involved are still unknown and the exact role of each viral component remains controversial [ 7 ]. (biomedcentral.com)
  • These experiments were part of a series that subsequently led to studies of nuclear reprogramming, directly relevant to stem cell research. (wikipedia.org)
  • However, a functional NLS could not be identified in another nuclear protein simply on the basis of similarity to the SV40 NLS. (wikipedia.org)
  • Using a protein called nucleoplasmin, the archetypal 'molecular chaperone', they identified a domain in the protein that acts as a signal for nuclear entry. (wikipedia.org)
  • We further found that two domains of DEV pUL47, amino acids (aa) 40 to 50 and 768 to 777, could function as nuclear localization sequence (NLS) to guide the nuclear localization of pUL47 and nuclear translocation of heterologous proteins, including enhanced green fluorescent protein (EGFP) and beta-galactosidase (β-Gal). (biomedcentral.com)
  • In addition, residues 40 to 50 and 768 to 777 were necessary for nuclear localization of pUL47 and nuclear translocation of heterologous proteins. (biomedcentral.com)
  • We found that RKIP interacts with the nuclear transport factor importin α in BT-20 and MDA-MB-231 human breast cancer cells, suggesting importin-mediated active nuclear translocation. (bvsalud.org)
  • These types of NLSs can be further classified as either monopartite or bipartite. (wikipedia.org)
  • The major structural differences between the two are that the two basic amino acid clusters in bipartite NLSs are separated by a relatively short spacer sequence (hence bipartite - 2 parts), while monopartite NLSs are not. (wikipedia.org)
  • proposed the consensus sequence K-K/R-X-K/R for monopartite NLSs. (wikipedia.org)
  • carried out comparative mutagenesis on the nuclear localization signals of SV40 T-Antigen (monopartite), C-myc (monopartite), and nucleoplasmin (bipartite), and showed amino acid features common to all three. (wikipedia.org)
  • We also explored using specific models for the monopartite and bipartite NLSs, but surprisingly, found no significant improvement in positive predictive value. (biomedcentral.com)
  • A nuclear localization signal or sequence (NLS) is an amino acid sequence that 'tags' a protein for import into the cell nucleus by nuclear transport. (wikipedia.org)
  • In this paper, we present an analysis of characterized NLSs in yeast, and find, despite the large number of nuclear import pathways, that NLSs seem to show similar patterns of amino acid residues. (biomedcentral.com)
  • Therefore, other computational methods have been proposed to predict NLSs based on amino acid sequences. (biomedcentral.com)
  • A Chelsky sequence may, therefore, be part of the downstream basic cluster of a bipartite NLS. (wikipedia.org)
  • There are many other types of NLS, such as the acidic M9 domain of hnRNP A1, the sequence KIPIK in yeast transcription repressor Matα2, and the complex signals of U snRNPs. (wikipedia.org)
  • Of the many import pathways that exist in yeast, the best characterized is termed the 'classical' NLS pathway. (biomedcentral.com)
  • We show that our method is able to consistently find 37% of the NLSs with a low false positive rate and that our method retains its true positive rate outside of the yeast data set used for the training parameters. (biomedcentral.com)
  • We compiled a list of experimentally verified NLSs in yeast and found that PredictNLS [ 8 ] predicts 10% of the NLSs in this set. (biomedcentral.com)
  • We searched the literature for papers in which specific stretches of amino acids have been shown to act as functional NLSs in yeast. (biomedcentral.com)
  • compared the nuclear localization efficiencies of eGFP fused NLSs of SV40 Large T-Antigen, nucleoplasmin (AVKRPAATKKAGQAKKKKLD), EGL-13 (MSRRRKANPTKLSENAKKLAKEVEN), c-Myc (PAAKRVKLD) and TUS-protein (KLKIKRPVK) through rapid intracellular protein delivery. (wikipedia.org)
  • Raf kinase inhibitor protein (RKIP) is a multifunctional modulator of intracellular signal transduction. (bvsalud.org)
  • Both signals are recognized by importin α. (wikipedia.org)
  • Importin α contains a bipartite NLS itself, which is specifically recognized by importin β. (wikipedia.org)
  • Most of these NLSs appear to be recognized directly by specific receptors of the importin β family without the intervention of an importin α-like protein. (wikipedia.org)
  • Mechanistic studies show that, independent of its transactivation function, p53K316P interacts with lactate dehydrogenase B (LDHB) and alters the composition and enzymatic activities of LDH complex favoring pyruvate generation and hindering lactate production. (bvsalud.org)
  • They found significantly higher nuclear localization efficiency of c-Myc NLS compared to that of SV40 NLS. (wikipedia.org)
  • Evaluating the biological function of nuclear localization of RKIP, we found that the presence of the putative NLS is important for the role of RKIP in mitotic checkpoint regulation in MCF-7 human breast cancer cells. (bvsalud.org)
  • Cytoplasmic localization of BMP2K is managed by inhibition of NLS function through phosphorylation of Ser-1010 and by a newly found cytoplasmic localization region that antagonizes the NLS. (bvsalud.org)
  • The NLS of nucleoplasmin, KR[PAATKKAGQA]KKKK, is the prototype of the ubiquitous bipartite signal: two clusters of basic amino acids, separated by a spacer of about 10 amino acids. (wikipedia.org)
  • Point mutation of all the basic residues in the putative NLS of RKIP particularly strongly reduces nuclear localization. (bvsalud.org)
  • Although most of its functions have been considered cytosolic, we show here that the localization of RKIP is primarily nuclear in both growing and quiescent Madin-Darby canine kidney epithelial cells and in Cal-51 and BT-20 human breast cancer cells. (bvsalud.org)
  • Here we show the element that controls BMP2K's LLPS and cytoplasmic localization. (bvsalud.org)
  • In this study, high-resolution confocal light microscopy is used to explore the localisation of SUN3 and SUN4 in the perinuclear region, to explore topology and to study the role of mid-SUNs on endoplasmic reticulum morphology. (brookes.ac.uk)
  • We find that the p53K316P mutation increases cytoplasmic localization of p53 and promotes a pleiotropic metabolic phenotype that includes increased adiposity, increased de novo lipogenesis, and decreased lactate generation. (bvsalud.org)
  • Typically, this signal consists of one or more short sequences of positively charged lysines or arginines exposed on the protein surface. (wikipedia.org)