scholarly journals Protein Kinase KIS Localizes to RNA Granules and Enhances Local Translation

2008 ◽  
Vol 29 (3) ◽  
pp. 726-735 ◽  
Author(s):  
Serafí Cambray ◽  
Neus Pedraza ◽  
Marta Rafel ◽  
Eloi Garí ◽  
Martí Aldea ◽  
...  
Keyword(s):  
Cortical Neurons ◽  
Molecular Mechanisms ◽  
Local Translation ◽  
Serine Threonine Kinase ◽  
Threonine Kinase ◽  
Rna Granules ◽  
Axon Development ◽  
Brain Extracts ◽  
Cultured Cortical Neurons ◽  
Actin Mrna

ABSTRACT The regulation of mRNA transport is a fundamental process for cytoplasmic sorting of transcripts and spatially controlled translational derepression once properly localized. There is growing evidence that translation is locally modulated as a result of specific synaptic inputs. However, the underlying molecular mechanisms that regulate this translational process are just emerging. We show that KIS, a serine/threonine kinase functionally related to microtubule dynamics and axon development, interacts with three proteins found in RNA granules: KIF3A, NonO, and eEF1A. KIS localizes to RNA granules and colocalizes with the KIF3A kinesin and the β-actin mRNA in cultured cortical neurons. In addition, KIS is found associated with KIF3A and 10 RNP-transported mRNAs in brain extracts. The results of knockdown experiments indicate that KIS is required for normal neurite outgrowth. More important, the kinase activity of KIS stimulates 3′ untranslated region-dependent local translation in neuritic projections. We propose that KIS is a component of the molecular device that modulates translation in RNA-transporting granules as a result of local signals.

Involvement of PKCe in the Negative Regulation of Akt Activation Stimulated by G-CSF.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2187-2187
Author(s):  
Hong Liu ◽  
Fan Dong
Keyword(s):  
Molecular Mechanisms ◽  
Specific Inhibitor ◽  
Inhibitory Effect ◽  
Signaling Cascades ◽  
Granulocytic Differentiation ◽  
Serine Threonine Kinase ◽  
Akt Activation ◽  
Threonine Kinase ◽  
Receptor Mutant

Abstract Granulocyte colony-stimulating factor (G-CSF) supports the proliferation, differentiation and survival of myeloid cells by stimulating the activation of several signaling cascades including the serine/threonine kinase Akt pathway. Akt activation has been shown to be important for G-CSF-induced survival and granulocytic differentiation. Although significant progresses have been made in our understanding of the molecular mechanisms by which Akt is activated, much less is known about the signaling events that negatively regulate Akt activation. Interestingly, G-CSF-induced activation of Akt was completely inhibited when myeloid 32D cells transfected with the wild type G-CSF receptor were incubated with phorbol-12-myristate 13-acetate (PMA), a PKC activator. PMA-mediated inhibition of Akt activation occurred with 5 min and lasted at least 1 hour. Previously, it has been shown that a carboxyl terminally truncated G-CSF receptor (D715), whose expression is associated with the development of acute myeloid leukemia in patients with severe congenital neutropenia (SCN), mediates significantly prolonged Akt activation. Notably, Akt activation by G-CSF in 32D cells expressing the D715 receptor mutant was rapidly downregulated by PMA treatment. The inhibitory effect of PMA on Akt activation was abolished by pretreatment of cells with the specific PKC inhibitor GF109203X, suggesting that PKC-dependent pathway negatively regulates Akt activation. Ro-31-7549, a specific inhibitor of PKCe, also abrogated PMA-mediated inhibition of Akt activation whereas rottlerin and Go6976, inhibitors of PKCd and PKC a/bI,, respectively, displayed no effect. Together, these results identified PKCe as being critically involved in PMA-mediated inhibition of Akt activation. Experiments are currently under way to determine the mechanism by which PKCe downregulates Akt activation and the role of PKCe in the regulation of cell proliferation, differentiation and survival in response to G-CSF.

The endoplasmic reticulum/mitochondria interface: a subcellular platform for the orchestration of the functions of the PINK1–Parkin pathway?

2015 ◽  
Vol 43 (2) ◽  
pp. 297-301 ◽  
Author(s):  
Zoi Erpapazoglou ◽  
Olga Corti
Keyword(s):  
Endoplasmic Reticulum ◽  
Molecular Mechanisms ◽  
Mitochondrial Dynamics ◽  
Serine Threonine Kinase ◽  
Subcellular Compartment ◽  
Ubiquitin Protein Ligase ◽  
Threonine Kinase ◽  
Parkinsonian Syndromes ◽  
Phosphatase And Tensin Homologue ◽  
Familial Parkinson’S Disease

Mitochondrial dysfunction is a hallmark of both idiopathic and familial Parkinson's disease (PD). Mutations in the PARK2 and PARK6 genes, coding for the cytosolic E3 ubiquitin protein ligase Parkin and the mitochondrial serine/threonine kinase PINK1 [phosphatase and tensin homologue (PTEN)-induced putative kinase 1], lead to clinically similar early-onset Parkinsonian syndromes. PINK1 and Parkin cooperate within a conserved pathway to preserve mitochondrial quality through the regulation of a variety of processes, including mitochondrial dynamics, transport, bioenergetics, biogenesis and turnover. The molecular mechanisms behind the orchestration of this plethora of functions remain poorly understood. In the present review, we emphasize the functional overlap between the PINK1–Parkin pathway and the endoplasmic reticulum (ER)-mitochondria interface, a subcellular compartment critically involved in neurodegeneration. We discuss how this compartment may constitute a hub for the spatiotemporal organization of the activities of the PINK1–Parkin pathway.

scholarly journals Efficient differentiation and polarization of primary cultured neurons on poly(lactic acid) scaffolds with microgrooved structures

2019 ◽  
Author(s):  
Asako Otomo ◽  
Mahoko Takahashi Ueda ◽  
Toshinori Fujie ◽  
Arihiro Hasebe ◽  
Yosuke Okamura ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Cell Adhesion ◽  
Cortical Neurons ◽  
Molecular Mechanisms ◽  
Cultured Cells ◽  
Structural Features ◽  
Poly Lactic Acid ◽  
Adhesion Properties ◽  
Expression Of Genes ◽  
Cultured Cortical Neurons

AbstractSynthetic biodegradable polymers including poly(lactic acid) (PLA) are attractive cell culture substrates because their surfaces can be micropatterned to support cell adhesion. The cell adhesion properties of a scaffold mainly depend on its surface chemical and structural features; however, it remains unclear how these characteristics affect the growth and differentiation of cultured cells or their gene expression. In this study, we fabricated two differently structured PLA nanosheets: flat and microgrooved. We assessed the growth and differentiation of mouse primary cultured cortical neurons on these two types of nanosheets after pre-coating with poly-D-lysine and vitronectin. Interestingly, prominent neurite bundles were formed along the grooves on the microgrooved nanosheets, whereas thin and randomly extended neurites were only observed on the flat nanosheets. Comparative RNA sequencing analyses revealed that the expression of genes related to postsynaptic density, dendritic shafts, and asymmetric synapses was significantly and consistently up-regulated in cells cultured on the microgrooved nanosheets when compared with those cultured on the flat nanosheets. These results indicate that microgrooved PLA nanosheets can provide a powerful means of establishing a culture system for the efficient and reproducible differentiation of neurons, which will facilitate future investigations of the molecular mechanisms underlying the pathogenesis of neurological disorders.

scholarly journals A Pseudorabies Virus Serine/Threonine Kinase, US3, Promotes Retrograde Transport in Axons via Akt/mToRC1

2022 ◽  
Author(s):  
Andrew D. Esteves ◽  
Orkide O. Koyuncu ◽  
Lynn W. Enquist
Keyword(s):  
Cell Body ◽  
Pseudorabies Virus ◽  
Retrograde Transport ◽  
Productive Infection ◽  
Local Translation ◽  
Serine Threonine Kinase ◽  
Long Distance ◽  
Threonine Kinase ◽  
Mtorc1 Signaling ◽  
Axonal Translation

Infection of peripheral axons by alpha herpesviruses (AHVs) is a critical stage in establishing a life-long infection in the host. Upon entering the cytoplasm of axons, AHV nucleocapsids and associated inner-tegument proteins must engage the cellular retrograde transport machinery to promote the long-distance movement of virion components to the nucleus. The current model outlining this process is incomplete and further investigation is required to discover all viral and cellular determinants involved as well as the temporality of the events. Using a modified tri-chamber system, we have discovered a novel role of the pseudorabies virus (PRV) serine/threonine kinase, US3, in promoting efficient retrograde transport of nucleocapsids. We discovered that transporting nucleocapsids move at similar velocities both in the presence and absence of a functional US3 kinase; however fewer nucleocapsids are moving when US3 is absent and move for shorter periods of time before stopping, suggesting US3 is required for efficient nucleocapsid engagement with the retrograde transport machinery. This led to fewer nucleocapsids reaching the cell bodies to produce a productive infection 12hr later. Furthermore, US3 was responsible for the induction of local translation in axons as early as 1hpi through the stimulation of a PI3K/Akt-mToRC1 pathway. These data describe a novel role for US3 in the induction of local translation in axons during AHV infection, a critical step in transport of nucleocapsids to the cell body. Importance Neurons are highly polarized cells with axons that can reach centimeters in length. Communication between axons at the periphery and the distant cell body is a relatively slow process involving the active transport of chemical messengers. There’s a need for axons to respond rapidly to extracellular stimuli. Translation of repressed mRNAs present within the axon occurs to enable rapid, localized responses independently of the cell body. AHVs have evolved a way to hijack local translation in the axons to promote their transport to the nucleus. We have determined the cellular mechanism and viral components involved in the induction of axonal translation. The US3 serine/threonine kinase of PRV activates Akt-mToRC1 signaling pathways early during infection to promote axonal translation. When US3 is not present, the number of moving nucleocapsids and their processivity are reduced, suggesting that US3 activity is required for efficient engagement of nucleocapsids with the retrograde transport machinery.

scholarly journals A pseudorabies virus serine/threonine kinase, US3, promotes retrograde transport in axons via Akt/mToRC1

2021 ◽  
Author(s):  
Andrew D. Esteves ◽  
Orkide O Koyuncu ◽  
Lynn W. Enquist
Keyword(s):  
Pseudorabies Virus ◽  
Current Model ◽  
Retrograde Transport ◽  
Productive Infection ◽  
Local Translation ◽  
Serine Threonine Kinase ◽  
Long Distance ◽  
Threonine Kinase ◽  
Tegument Proteins ◽  
Long Distance Movement

Infection of peripheral axons by alpha herpesviruses (AHVs) is a critical stage in establishing a life-long infection in the host. Upon entering the cytoplasm of axons, AHV nucleocapsids and associated inner-tegument proteins must engage the cellular retrograde transport machinery to promote the long-distance movement of virion components to the nucleus. The current model outlining this process is incomplete and further investigation is required to discover all viral and cellular determinants involved as well as the temporality of the events. Using a modified tri-chamber system, we have discovered a novel role of the pseudorabies virus (PRV) serine/threonine kinase, US3, in promoting efficient retrograde transport of nucleocapsids. We discovered that transporting nucleocapsids move at similar velocities both in the presence and absence of a functional US3 kinase; however fewer nucleocapsids are moving when US3 is absent and move for shorter periods of time before stopping, suggesting US3 is required for efficient nucleocapsid engagement with the retrograde transport machinery. This led to fewer nucleocapsids reaching the cell bodies to produce a productive infection 12hr later. Furthermore, US3 was responsible for the induction of local translation in axons as early as 1hpi through the stimulation of a PI3K/Akt-mToRC1. These data describe a novel role for US3 in the induction of local translation in axons during AHV infection, a critical step in transport of nucleocapsids to the cell body.

CDKL5 Gene: Beyond Rett Syndrome

2021 ◽  
Author(s):  
Lina Maria Ciccia ◽  
Bruna Scalia ◽  
Valeria Venti ◽  
Francesco Pizzo ◽  
Maria Grazia Pappalardo ◽  
...  
Keyword(s):  
Motor Development ◽  
Synapse Formation ◽  
Drug Resistant ◽  
Therapeutic Approaches ◽  
Serine Threonine Kinase ◽  
Ataxic Gait ◽  
Actual Knowledge ◽  
Threonine Kinase ◽  
Axon Development ◽  
Development Delay

Abstract CDKL5 is a gene located in the X-chromosome (Xp22) encoding a serine/threonine kinase involved in various signaling pathways, implicated in cell proliferation, axon development, dendrite growth, synapse formation, and maintenance. Mutations occurring in this gene have been associated with drug-resistant early-onset epilepsy, with multiple seizures type, and deep cognitive and motor development delay with poor or absent speech, ataxic gait or inability to walk, hand stereotypies and in a few cases decrement of head growth. Many aspects remain unclear about the CDKL5 deficiency disorders, research will be fundamental to better understand the pathogenesis of neurological damage and consequently developed more targeted and profitable therapies, as there is not, at the present, a gene-based treatment and the seizures are in most of the cases drug resistant. In this article, we summarize the actual knowledge about CDKL5 gene function and mostly the consequence given by its dysfunction, also examining the possible therapeutic approaches.

scholarly journals SMADS-mediate Molecular Mechanisms in Sjӧgren's Syndrome

2021 ◽  
Author(s):  
Margherita Sisto ◽  
Domenico Ribatti ◽  
Sabrina Lisi
Keyword(s):  
Therapeutic Strategy ◽  
Molecular Mechanisms ◽  
Target Genes ◽  
Transforming Growth Factor ◽  
Biological Effects ◽  
Serine Threonine Kinase ◽  
Threonine Kinase ◽  
Signalling Molecules ◽  
Disease Markers ◽  
Membrane Bound

There is considerable interest in delineating the molecular mechanisms of action of transforming growth factor-β (TGF-β), considered as central player in a plethora of human conditions, including cancer, fibrosis and autoimmune disease. TGF-β elicits its biological effects through membrane bound serine/threonine kinase receptors which transmit their signals via downstream signalling molecules, SMADs, which regulate the transcription of target genes in collaboration with various co-activators and co-repressors. Until now, therapeutic strategy for primary Sjӧgren’s syndrome (pSS) has been focused on inflammation, but, recently, the involvement of TGF-β/SMADs signalling has been demonstrated in pSS, although TGFβ family members seems to have ambiguous effects on the function of pSS salivary glands. Based on these premises, this review highlights recent advances in unravelling the molecular basis for the multi-faceted functions of TGF-β in pSS that are dictated by orchestrations of SMADs, and describe TGF-β/SMADs value as both disease markers and/or therapeutic target for pSS.

scholarly journals Multiple Mitogen-Activated Protein Kinase Signaling Pathways Connect the Cot Oncoprotein to the c-junPromoter and to Cellular Transformation

2000 ◽  
Vol 20 (5) ◽  
pp. 1747-1758 ◽  
Author(s):  
Mario Chiariello ◽  
Maria Julia Marinissen ◽  
J. Silvio Gutkind
Keyword(s):  
Protein Kinase ◽  
Molecular Mechanisms ◽  
Cellular Transformation ◽  
Mitogen Activated Protein Kinase ◽  
Serine Threonine Kinase ◽  
Activated T Cells ◽  
Mapk Kinase ◽  
Threonine Kinase ◽  
Mitogen Activated Protein

ABSTRACT The serine/threonine kinase Cot is a member of the mitogen-activated protein kinase (MAPK) kinase kinase family implicated in cellular transformation. Enhanced expression of this protein has been shown to activate both the MAPK and the c-Jun N-terminal kinase (JNK) pathways and to stimulate the nuclear factor of activated T cells and NF-κB-dependent transcription. However, the nature of the normal functions of the Cot protein and the molecular mechanisms responsible for its oncogenic potential are still largely unknown. Here, we show that overexpression of the cot proto-oncogene is sufficient to stimulate the expression of c-jun and that, in turn, the activity of c-Jun is required for Cot-induced transformation. These observations prompted us to explore the molecular events by which Cot regulates c-jun expression. We found that Cot potently stimulates the activity of the c-jun promoter utilizing JNK-dependent and -independent pathways, the latter involving two novel members of the MAPK family, p38γ (ERK6) and ERK5. Molecularly, this activity was found to be dependent on the ability of Cot to activate, in vivo, members of each class of the MAPK kinase superfamily, including MEK, SEK, MKK6, and MEK5. Furthermore, the use of dominant interfering molecules revealed that Cot requires JNK, p38s, and ERK5 to stimulate the c-jun promoter fully and to induce neoplastic transformation. These findings indicate that Cot represents the first example of a serine/threonine kinase acting simultaneously on all known MAPK cascades. Moreover, these observations strongly suggest that the transforming ability of Cot results from the coordinated activation of these pathways, which ultimately converge on the regulation of the expression and activity of the product of the c-junproto-oncogene.

scholarly journals Postsynaptic Targeting and Mobility of Membrane Surface-Localized hASIC1a

2020 ◽  
Author(s):  
Xing-Lei Song ◽  
Di-Shi Liu ◽  
Min Qiang ◽  
Qian Li ◽  
Ming-Gang Liu ◽  
...  
Keyword(s):  
Cortical Neurons ◽  
Molecular Mechanisms ◽  
Membrane Surface ◽  
Single Particle Tracking ◽  
Synaptic Activity ◽  
Long Distance ◽  
Synaptic Functions ◽  
Cultured Cortical Neurons ◽  
The Central Nervous System ◽  
High Dynamics

Abstract Acid-sensing ion channels (ASICs), the main H+ receptors in the central nervous system, sense extracellular pH fluctuations and mediate cation influx. ASIC1a, the major subunit responsible for acid-activated current, is widely expressed in brain neurons, where it plays pivotal roles in diverse functions including synaptic transmission and plasticity. However, the underlying molecular mechanisms for these functions remain mysterious. Using extracellular epitope tagging and a novel antibody recognizing the hASIC1a ectodomain, we examined the membrane targeting and dynamic trafficking of hASIC1a in cultured cortical neurons. Surface hASIC1a was distributed throughout somata and dendrites, clustered in spine heads, and co-localized with postsynaptic markers. By extracellular pHluorin tagging and fluorescence recovery after photobleaching, we detected movement of hASIC1a in synaptic spine heads. Single-particle tracking along with use of the anti-hASIC1a ectodomain antibody revealed long-distance migration and local movement of surface hASIC1a puncta on dendrites. Importantly, enhancing synaptic activity with brain-derived neurotrophic factor accelerated the trafficking and lateral mobility of hASIC1a. With this newly-developed toolbox, our data demonstrate the synaptic location and high dynamics of functionally-relevant hASIC1a on the surface of excitatory synapses, supporting its involvement in synaptic functions.

scholarly journals Determination of the Time Course and Extent of Neurotoxicity at Defined Temperatures in Cultured Neurons Using a Modified Multiwell Plate Fluorescence Scanner

1997 ◽  
Vol 17 (4) ◽  
pp. 455-463 ◽  
Author(s):  
Rita Sattler ◽  
Milton P. Charlton ◽  
Mathias Hafner ◽  
Michael Tymianski
Keyword(s):  
High Throughput ◽  
Cortical Neurons ◽  
Time Course ◽  
Molecular Mechanisms ◽  
Neuronal Cultures ◽  
Lactate Dehydrogenase Release ◽  
Cultured Cortical Neurons ◽  
And Control

The cellular and molecular mechanisms of hypoxic/ischemic neurodegeneration are sensitive to numerous factors that modulate the time course and degree of neuronal death. Among such factors is hypothermia, which can dramatically protect neurons from injury. To examine and control for temperature-dependent effects, we developed a technique that provides for a high-throughput, accurate, and reproducible determination of the time course and degree of neurotoxicity in cultured cortical neurons at precisely defined temperatures. We used a fluorescence multiwell plate scanner, modified by us to permit the control of temperature, to perform serial quantitative measurements of propidium iodide (PI) fluorescence in cortical neuronal cultures exposed to excitotoxic insults. In validating this approach, we show that these time course measurements correlate highly with manual counts of PI-stained cells in the same cultures ( r = 0.958, p < 0.0001) and with lactate dehydrogenase release ( r = 0.964, p < 0.0001). This method represents an efficient approach to mechanistic and quantitative studies of cell death as well as a high-throughput technique for screening new neuroprotective therapies in vitro.

Sign in / Sign up

Export Citation Format

Share Document