keyword
MENU ▼
Read by QxMD icon Read
search

importin

keyword
https://www.readbyqxmd.com/read/28216671/dual-mechanisms-regulate-the-nucleocytoplasmic-localization-of-human-ddx6
#1
Jo-Hsi Huang, Wei-Chi Ku, Yen-Chun Chen, Yi-Ling Chang, Chia-Ying Chu
DDX6 is a conserved DEAD-box protein (DBP) that plays central roles in cytoplasmic RNA regulation, including processing body (P-body) assembly, mRNA decapping, and translational repression. Beyond its cytoplasmic functions, DDX6 may also have nuclear functions because its orthologues are known to localize to nuclei in several biological contexts. However, it is unclear whether DDX6 is generally present in human cell nuclei, and the molecular mechanism underlying DDX6 subcellular distribution remains elusive...
February 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28205572/ran-dependent-tpx2-activation-promotes-acentrosomal-microtubule-nucleation-in-neurons
#2
Wen-Shin Chen, Yi-Ju Chen, Yung-An Huang, Bing-Yuan Hsieh, Ho-Chieh Chiu, Pei-Ying Kao, Chih-Yuan Chao, Eric Hwang
The microtubule (MT) cytoskeleton is essential for the formation of morphologically appropriate neurons. The existence of the acentrosomal MT organizing center in neurons has been proposed but its identity remained elusive. Here we provide evidence showing that TPX2 is an important component of this acentrosomal MT organizing center. First, neurite elongation is compromised in TPX2-depleted neurons. In addition, TPX2 localizes to the centrosome and along the neurite shaft bound to MTs. Depleting TPX2 decreases MT formation frequency specifically at the tip and the base of the neurite, and these correlate precisely with the regions where active GTP-bound Ran proteins are enriched...
February 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28193700/the-nuclear-transport-receptor-importin-11-is-a-tumor-suppressor-that-maintains-pten-protein
#3
Muhan Chen, Dawid G Nowak, Navneet Narula, Brian Robinson, Kaitlin Watrud, Alexandra Ambrico, Tali M Herzka, Martha E Zeeman, Matthias Minderer, Wu Zheng, Saya H Ebbesen, Kendra S Plafker, Carlos Stahlhut, Victoria M Y Wang, Lorna Wills, Abu Nasar, Mireia Castillo-Martin, Carlos Cordon-Cardo, John E Wilkinson, Scott Powers, Raffaella Sordella, Nasser K Altorki, Vivek Mittal, Brendon M Stiles, Scott M Plafker, Lloyd C Trotman
Phosphatase and tensin homologue (PTEN) protein levels are critical for tumor suppression. However, the search for a recurrent cancer-associated gene alteration that causes PTEN degradation has remained futile. In this study, we show that Importin-11 (Ipo11) is a transport receptor for PTEN that is required to physically separate PTEN from elements of the PTEN degradation machinery. Mechanistically, we find that the E2 ubiquitin-conjugating enzyme and IPO11 cargo, UBE2E1, are limiting factors for PTEN degradation...
February 13, 2017: Journal of Cell Biology
https://www.readbyqxmd.com/read/28193699/importin-11-keeps-pten-safe-from-harm
#4
Nick R Leslie
In this issue, Chen et al. (2017. J. Cell Biol. https://doi.org/10.1083/jcb.201604025) show that Importin-11 traffics the tumor suppressor PTEN into the nucleus and in so doing protects it from cytoplasmic proteins that cause PTEN degradation. This work helps explain the nuclear accumulation of PTEN observed in many healthy tissues and, because Ipo11 mutant mice develop lung tumors, also implicates Importin-11 as a novel tumor suppressor.
February 13, 2017: Journal of Cell Biology
https://www.readbyqxmd.com/read/28187450/nucleocytoplasmic-shuttling-of-sox14a-and-sox14b-transcription-factors
#5
Zhen-Yu She, Wan-Xi Yang
The nucleocytoplasmic shuttling of SOX transcription factors play a crucial role in the regulation of SOX protein functions during development. In this study, we have demonstrated two nuclear localization signals in the HMG box of Eriocheir sinensis SOX14A and SOX14B. These two conserved nuclear localization signals mediate nuclear transport. The N-termini nuclear localization signal mediates the calmodulin-dependent pathway and the C-termini nuclear localization signal interacts with the importin-β pathway...
February 7, 2017: Oncotarget
https://www.readbyqxmd.com/read/28187419/dynamics-of-mirna-biogenesis-and-nuclear-transport
#6
Aneesh Kotipalli, Ravikumar Gutti, Chanchal K Mitra
MicroRNAs (miRNAs) are short noncoding RNA sequences ~22 nucleotides in length that play an important role in gene regulation-transcription and translation. The processing of these miRNAs takes place in both the nucleus and the cytoplasm while the final maturation occurs in the cytoplasm. Some mature miRNAs with nuclear localisation signals (NLS) are transported back to the nucleus and some remain in the cytoplasm. The functional roles of these miRNAs are seen in both the nucleus and the cytoplasm. In the nucleus, miRNAs regulate gene expression by binding to the targeted promoter sequences and affect either the transcriptional gene silencing (TGS) or transcriptional gene activation (TGA)...
December 22, 2016: Journal of Integrative Bioinformatics
https://www.readbyqxmd.com/read/28179529/differential-disruption-of-nucleocytoplasmic-trafficking-pathways-by-rhinovirus-2a-proteases
#7
Kelly Watters, Bahar Inankur, Jaye C Gardiner, Jay Warrick, Nathan M Sherer, John Yin, Ann C Palmenberg
The RNA rhinoviruses (RV) encode 2A proteases (2A(pro)) that contribute essential polyprotein processing and host-cell shutoff functions during infection, including the cleavage of Phe/Gly-containing nucleoporin proteins (Nups) within nuclear pore complexes (NPC). Within the 3 RV species, multiple divergent genotypes encode diverse 2A(pro) sequences which act differentially on specific Nups. Since only subsets of Phe/Gly motifs, particularly those within Nup62, Nup98 and Nup153, are recognized by transport receptors (karyopherins) when trafficking large molecular cargos through the NPC, the processing preferences of individual 2A(pro) predict RV genotype-specific targeting of NPC pathways and cargos...
February 8, 2017: Journal of Virology
https://www.readbyqxmd.com/read/28166455/structural-and-mechanistic-insights-into-nuclear-transport-and-delivery-of-the-critical-pluripotency-factor-oct4-to-dna
#8
Takahide Okuyama, Ryosuke Yamagishi, Jiro Shimada, Masaaki Ikeda, Yayoi Maruoka, Hiroki Kaneko
Oct4 is a master regulator of the induction and maintenance of cellular pluripotency, and has crucial roles in early stages of differentiation. It is the only factor that cannot be substituted by other members of the same protein family to induce pluripotency. However, although Oct4 nuclear transport and delivery to target DNA are critical events for reprogramming to pluripotency, little is known about the molecular mechanism. Oct4 is imported to the nucleus by the classical nuclear transport mechanism, which requires importin α as an adaptor to bind the nuclear localization signal (NLS)...
February 6, 2017: Journal of Biomolecular Structure & Dynamics
https://www.readbyqxmd.com/read/28163061/importins-in-the-maintenance-and-lineage-commitment-of-es-cells
#9
REVIEW
Noriko Yasuhara, Yoshihiro Yoneda
The nucleus of a eukaryotic cell is separated from the cytoplasm by a nuclear envelope, and nuclear pores within the envelope facilitate nucleocytoplasmic transport and the exchange of information. Gene regulation is a key component of biological activity regulation in the cell. Transcription factors control the expression levels of various genes that are necessary for the maintenance or conversion of cellular states during animal development. Because transcription factor activities determine the extent of transcription of target genes, the number of active transcription factors must be tightly regulated...
February 2, 2017: Neurochemistry International
https://www.readbyqxmd.com/read/28148649/c3g-shows-regulated-nucleo-cytoplasmic-exchange-and-represses-histone-modifications-associated-with-euchromatin
#10
Dhruv Kumar Shakyawar, Kunal Dayma, Anesh Ramadhas, Chavvakula Varalakshmi, Vegesna Radha
C3G (RapGEF1) is a ubiquitously expressed guanine nucleotide exchange factor that functions in signaling pathways regulating cell proliferation, apoptosis, and actin reorganization. It is essential for differentiation, and early embryonic development in mice. Over-expressed C3G shows predominant cytoplasmic localization, but endogenous C3G is a component of nuclear fractions in a variety of cell types. Co-expression of Importin-α and inhibition of nuclear export by Leptomycin B resulted in predominant nuclear localization of C3G...
February 1, 2017: Molecular Biology of the Cell
https://www.readbyqxmd.com/read/28125336/new-insights-into-mechanisms-of-nuclear-translocation-of-g-protein-coupled-receptors
#11
Vikrant K Bhosle, José Carlos Rivera, Sylvain Chemtob
The G-protein coupled receptor (GPCR) signaling was long believed to involve activation of receptor exclusively at the cell surface, followed by its binding to heterotrimeric G-proteins and arrestins to trigger various intracellular signaling cascades, and termination of signaling by internalization of the receptor. It is now accepted that many GPCRs continue to signal after internalization in the endosomes. Since the breakthrough discoveries of nuclear binding sites for their ligands in 1980s, several GPCRs have been detected at cell nuclei...
January 26, 2017: Small GTPases
https://www.readbyqxmd.com/read/28117667/extensive-cargo-identification-reveals-distinct-biological-roles-of-the-12-importin-pathways
#12
Makoto Kimura, Yuriko Morinaka, Kenichiro Imai, Shingo Kose, Paul Horton, Naoko Imamoto
Vast numbers of proteins are transported into and out of the nuclei by approximately 20 species of importin-β family nucleocytoplasmic transport receptors. However, the significance of the multiple parallel transport pathways that the receptors constitute is poorly understood because only limited numbers of cargo proteins have been reported. Here, we identified cargo proteins specific to the 12 species of human import receptors with a high-throughput method that employs stable isotope labeling with amino acids in cell culture, an in vitro reconstituted transport system, and quantitative mass spectrometry...
January 24, 2017: ELife
https://www.readbyqxmd.com/read/28104399/structural-basis-for-the-regulation-of-nuclear-import-of-epstein-barr-virus-nuclear-antigen-1-ebna1-by-phosphorylation-of-the-nuclear-localization-signal
#13
Ryohei Nakada, Hidemi Hirano, Yoshiyuki Matsuura
Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) is expressed in every EBV-positive tumor and is essential for the maintenance, replication, and transcription of the EBV genome in the nucleus of host cells. EBNA1 is a serine phosphoprotein, and it has been shown that phosphorylation of S385 in the nuclear localization signal (NLS) of EBNA1 increases the binding affinity to the nuclear import adaptor importin-α1 as well as importin-α5, and stimulates nuclear import of EBNA1. To gain insights into how phosphorylation of the EBNA1 NLS regulates nuclear import, we have determined the crystal structures of two peptide complexes of importin-α1: one with S385-phosphorylated EBNA1 NLS peptide, determined at 2...
January 17, 2017: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/28100513/loss-of-ranbp2-in-motor-neurons-causes-the-disruption-of-nucleocytoplasmic-and-chemokine-signaling-and-proteostasis-of-hnrnph3-and-mmp28-and-the-development-of-amyotrophic-lateral-sclerosis-als-like-syndromes
#14
Kyoung-In Cho, Dosuk Yoon, Sunny Qiu, Zachary Danziger, Warren M Grill, William C Wetsel, Paulo A Ferreira
The pathogenic drivers of sporadic and familial motor neuron disease (MND), such ALS, are unknown. MND impair the Ran GTPase cycle, which controls nucleocytoplasmic transport, ribostasis and proteostasis; however, cause-effect mechanisms of Ran GTPase modulators in motoneuron pathobiology are heretofore elusive. The cytosolic and peripheral nucleoporin, Ranbp2, is a critical regulator of the Ran GTPase cycle and proteostasis of neurological disease-prone substrates, but the roles of Ranbp2 in motoneuron biology and disease remain unknown...
January 18, 2017: Disease Models & Mechanisms
https://www.readbyqxmd.com/read/28077622/ciliary-entry-of-kif17-is-dependent-on-its-binding-to-the-ift-b-complex-via-ift46-ift56-as-well-as-on-its-nuclear-localization-signal
#15
Teruki Funabashi, Yohei Katoh, Saki Michisaka, Masaya Terada, Maho Sugawa, Kazuhisa Nakayama
Cilia function as cellular antennae to sense and transduce extracellular signals. A number of proteins are specifically localized in cilia. Anterograde and retrograde ciliary protein trafficking are mediated by the IFT-B and IFT-A complexes in concert with kinesin-2 and dynein-2 motors, respectively. However, the role of KIF17, a homodimeric kinesin-2 protein, in protein trafficking has not been fully understood in vertebrate cilia. In this study, we first demonstrated by taking advantage of the visible immunoprecipitation assay, that KIF17 interacts with the IFT46-IFT56 dimer in the IFT-B complex through its C-terminal sequence located immediately upstream of the nuclear localization signal (NLS)...
January 11, 2017: Molecular Biology of the Cell
https://www.readbyqxmd.com/read/28075463/expression-of-the-promyelocytic-leukemia-protein-without-the-nuclear-localization-signal-as-a-novel-diagnostic-marker-for-acute-promyelocytic-leukemia
#16
Ting Xu, Xiao-Qun Yang, Kai-Ling Jiang, Hui Wang, Peng-Peng Ma, Liang Zhong, Bei-Zhong Liu
Promyelocytic leukemia-retinoic acid receptor α (PML-RARα) is a fusion protein generated by the t(15;17)(q22;q12) translocation associated with acute promyelocytic leukemia (APL). PML-RARα is cleaved by neutrophil elastase, an early myeloid-specific serine protease, leading to translocation of the nuclear localization signal (NLS) of the PML protein to the N-terminal of RARα, and the mutational product PML(NLS-). The present study was designed to analyze the role of the NLS in mediating PML transport into the nucleus and to evaluate the value of measuring NLS translocation in the early diagnosis of APL...
February 2017: Oncology Reports
https://www.readbyqxmd.com/read/28074610/an-in%C3%A2-vitro-model-yields-importin-new-insights-into-chronic-traumatic-encephalopathy-damaged-astrocytes-stop-thrombospondin-to-the-injury-an-editorial-highlight-for-defective-synthesis-and-release-of-astrocytic-thrombospondin-1-mediates-the-neuronal-tdp-43
#17
EDITORIAL
Sausan M Jaber, Brian M Polster
Read the highlighted article 'Defective synthesis and release of astrocytic thrombospondin-1 mediates the neuronal TDP-43 proteinopathy, resulting in defects in neuronal integrity associated with chronic traumatic encephalopathy: in vitro studies' on page 645.
February 2017: Journal of Neurochemistry
https://www.readbyqxmd.com/read/28071726/the-ppe2-protein-of-mycobacterium-tuberculosis-translocates-to-host-nucleus-and-inhibits-nitric-oxide-production
#18
Khalid Hussain Bhat, Shruti Srivastava, Sandeep Kumar Kotturu, Sudip Ghosh, Sangita Mukhopadhyay
Mycobacterium tuberculosis, the bacterium that causes tuberculosis, is one of the most successful pathogens of humans. It has evolved several adaptive skills and evasion mechanisms to hijack the immunologically educated host to suit its intracellular lifestyle. Here, we show that one of the unique PPE family member proteins of M. tuberculosis, PPE2, can limit nitric oxide (NO) production by inhibiting inos gene transcription. PPE2 protein has a leucine zipper DNA-binding motif and a functional nuclear localization signal...
January 10, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28054750/somatic-med12-nonsense-mutation-escapes-mrna-decay-and-reveals-a-motif-required-for-nuclear-entry
#19
Tuomas Heikkinen, Kati Kämpjärvi, Salla Keskitalo, Pernilla von Nandelstadh, Xiaonan Liu, Ville Rantanen, Esa Pitkänen, Matias Kinnunen, Heikki Kuusanmäki, Mika Kontro, Mikko Turunen, Netta Mäkinen, Jussi Taipale, Caroline Heckman, Kaisa Lehti, Satu Mustjoki, Markku Varjosalo, Pia Vahteristo
MED12 is a key component of the transcription-regulating Mediator complex. Specific missense and in-frame insertion/deletion mutations in exons 1 and 2 have been identified in uterine leiomyomas, breast tumors, and chronic lymphocytic leukemia. Here, we characterize the first MED12 5' end nonsense mutation (c.97G>T, p.E33X) identified in acute lymphoblastic leukemia and show that it escapes nonsense-mediated mRNA decay (NMD) by using an alternative translation initiation site. The resulting N-terminally truncated protein is unable to enter the nucleus due to the lack of identified nuclear localization signal (NLS)...
March 2017: Human Mutation
https://www.readbyqxmd.com/read/28040778/latrunculin-a-induced-perturbation-of-the-actin-cytoskeleton-mediates-pap1p-dependent-induction-of-the-caf5p-efflux-pump-in-schizosaccharomyces-pombe
#20
Farzad Asadi, Bidhan Chakraborty, Jim Karagiannis
As part of an earlier study aimed at uncovering gene-products with roles in defending against latrunculin A (LatA) induced cytoskeletal perturbations, we identified three members of the oxidative stress response pathway: the Pap1p AP-1 like transcription factor, the Imp1p importin-alpha, and the Caf5p efflux pump. In this report, we characterize the pathway further and show that Pap1p translocates from the cytoplasm to the nucleus in an Imp1p-dependent manner upon LatA treatment. Moreover, preventing this translocation -- through the addition of a nuclear export signal - confers the same characteristic LatA-sensitive phenotype exhibited by pap1Δ cells...
December 30, 2016: G3: Genes—Genomes—Genetics
keyword
keyword
70002
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"