1,555 research outputs found
Mechanisms Regulating the Association of Protein Phosphatase 1 with Spinophilin and Neurabin
Protein phosphorylation is a key mediator of signal transduction, allowing for dynamic regulation of substrate activity. Whereas protein kinases obtain substrate specificity by targeting specific amino acid sequences, serine/threonine phosphatase catalytic subunits are much more promiscuous in their ability to dephosphorylate substrates. To obtain substrate specificity, serine/threonine phosphatases utilize targeting proteins to regulate phosphatase subcellular localization and catalytic activity. Spinophilin and its homologue neurabin are two of the most abundant dendritic spine-localized protein phosphatase 1 (PP1) targeting proteins. The association between spinophilin and PP1 is increased in the striatum of animal models of Parkinson's disease (PD). However, mechanisms that regulate the association of spinophilin and neurabin with PP1 are unclear. Here, we report that the association between spinophilin and PP1α or PP1γ1 was increased by CDK5 expression and activation in a heterologous cell system. This increased association is at least partially due to phosphorylation of PP1. Conversely, CDK5 expression and activation decreased the association of PP1 with neurabin. As with dopamine depletion, methamphetamine (METH) abuse causes persistent alterations in dopamine signaling which influence striatal medium spiny neuron function and biochemistry. Moreover, both METH toxicity and dopamine depletion are associated with deficits in motor control and motor learning. Pathologically, we observed a decreased association of spinophilin with PP1 in rat striatum evaluated one month following a binge METH paradigm. Behaviorally, we found that loss of spinophilin recapitulates rotarod pathology previously observed in dopamine-depleted and METH-treated animals. Together, these data have implications in multiple disease states associated with altered dopamine signaling such as PD and psychostimulant drug abuse and delineate a novel mechanism by which PP1 interactions with spinophilin and neurabin may be differentially regulated
Studi Adopsi Varietas Bawang Merah Bima Brebes dari Balitsa di Kabupaten Brebes (Adoption Study Of Bima Brebes Shallot From IVEGRI In Brebes District)
Contribution of Indonesian Vegetable Research Institute (IVEGRI) as an institution who produces new technologies, including new varieties, on the improvement of farmers\u27 income has not been got completed information yet. The objectives of the research were to figure out the level of adoption and contribution of Bima Brebes shallot variety from IVEGRI in increasing adopter farmers\u27 profit, as well as to figure out the return on investment (ROI) of research and dissemination of Bima Brebes shallot. This expost evaluation research was conducted in June–December 2014 in Wanasari Village, Tanjung, Kemukten, and Limbangan, Brebes District. The location was chosen purposively because in the area there were a quite lot of farmers who adopted Bima Brebes shallot variety. Data were collected through Focus Group Discussion (FGD) and an individual interview used structured questionnaire. The respondents consisted of 16 Bima Brebes adopter shallot farmers and 21 nonadopters shallot farmers who planting Bima Curut variety. Data were analysed using descriptive statistic with time line picture. The result of study showed that the technology of Bima Brebes variety from IVEGRI has been disseminated since 1985 in Brebes District and currently, it has been adopting quiet large as well. The spreading adoption is about 16,522 ha. In 2013, the adoption of Bima Brebes in Brebes District could increase adopters\u27 profit as much as 345.050 billions rupiah with ROI of research and dissemination of the variety was 71,125%
The association of spinophilin with disks large-associated protein 3 (SAPAP3) is regulated by metabotropic glutamate receptor (mGluR) 5
Spinophilin is the most abundant protein phosphatase 1 targeting protein in the postsynaptic density of dendritic spines. Spinophilin associates with myriad synaptic proteins to regulate normal synaptic communication; however, the full complement of spinophilin interacting proteins and mechanisms regulating spinophilin interactions are unclear. Here we validate an association between spinophilin and the scaffolding protein, disks large-associated protein 3 (SAP90/PSD-95 associated protein 3; SAPAP3). Loss of SAPAP3 leads to obsessive-compulsive disorder (OCD)-like behaviors due to alterations in metabotropic glutamate receptor (mGluR) signaling. Here we report that spinophilin associates with SAPAP3 in the brain and in a heterologous cell system. Moreover, we have found that expression or activation of group I mGluRs along with activation of the mGluR-dependent kinase, protein kinase C β, enhances this interaction. Functionally, global loss of spinophilin attenuates amphetamine-induced hyperlocomotion, a striatal behavior associated with dopamine dysregulation and OCD. Together, these data delineate a novel link between mGluR signaling, spinophilin, and SAPAP3 in striatal pathophysiology
Does spinophilin play a role in alteration of NMDAR phosphorylation?
poster abstractNormal brain function requires proper organization of downstream signaling pathways. This organization can be modulated by protein phosphorylation. Protein phosphorylation is a balance of phosphatases, such as protein phosphatase 1 (PP1), and kinases such as protein kinase A (PKA) and cyclin dependent kinase 5 (CDK5). Proper targeting of these proteins is critical for their normal function and is perturbed in various disease states. Spinophilin is critical in targeting PP1 to various substrates making it important in regulating the phosphorylation state and thus the function of various proteins including glutamate receptors, such as AMPARs and NMDARs. NMDARs are abundant postsynaptic proteins that are critical for normal synaptic communication. It has been reported that NMDAR phosphorylation modulates channel function. Here we aim to understand if spinophilin regulates NMDAR phosphorylation and function as well as the mechanisms by which the spinophilin NMDAR interaction are altered. Specifically, we have found that the presence of spinophilin decreases the abundance of PP1 bound to NMDAR. This affect was not observed when a PP1 binding-deficient spinophilin mutant (F451A) was expressed. Furthermore, activation of endogenous PKA and/or overexpression of PKA catalytic subunit robustly increased the association between spinophilin and GluN1 and C-terminal tail of the GluN2B subunit of the NMDAR. Conversely, these associations are decreased when CDK5 is present. Our future studies will evaluate the role of spinophilin in regulating the phosphorylation state of the NMDAR. Taken together, our data demonstrate that spinophilin can associate with multiple subunits of the NMDAR in HEK293 cells and that protein kinases can biphasically modulate these associations
Randomized Treatment of Patients with Typhoid Fever by Using Ceftriaxone or Chloramphenicol
Sixty-three patients with Salmonella typhi infections were randomly assigned to receive either ceftriaxone iv in single daily doses of 75 mg/kg for children and 3-4 g for adults for seven days or to receive 60 mg of chloramphenicol/kg a day orally or iv in four divided doses until defervescence and then 40 mg/kg a day to complete 14 d. In the ceftriaxone group, one death occurred, and two of seven patients still febrile 11 d after starting treatment were given chloramphenicol. In the chloramphenicol group, one death and one gastrointestinal perforation occurred. The probability of remaining febrile was similar for both groups during the first seven days but was significantly greater for patients receiving ceftriaxone during the 14-dperiod. Patients in the chloramphenicol group weremore likely to be bacteremic on day 3. These results suggest that a seven-day course of once-daily ceftriaxone shows promise as an alternative to 14 d of chloramphenicol for treating typhoid feve
Impact of Transformational Leadership on Psychological Empowerment and Job Satisfaction Relationship: a Case of Yemeni Banking
The banking sector of Yemen is under threat due to the lack of confidence and trust of the prospective clients that hindered economic development of the country. The study aimed to measure a moderating effect of transformational leadership on employees\u27 psychological empowerment and job satisfaction relationship so that attitudes of the Yemeni can be bumped towards banking. In this study, 160 employees were surveyed in different branches of four banks in Yemen. The data were analyzed in four stages namely, reliability and validity analysis, descriptive analysis, multivariate analysis, and hypotheses testing analysis. The study revealed a significant positive relationship between employees\u27 psychological empowerment and transformational leadership towards their job satisfaction level. If the policy makers consider the findings and undertake necessary measures, the Yemeni banking is expected to be accelerated which will contribute to the economy of the country
Rapid preparation of pharmaceutical co-crystals with thermal ink-jet printing
Thermal ink-jet printing (TIJP) is shown to be a rapid (minutes) method with which to prepare pharmaceutical co-crystals; co-crystals were identified in all cases where the co-formers could be dissolved in water and/or water/ethanol solutions
Mechanisms and Consequences of Dopamine Depletion-Induced Attenuation of the Spinophilin/Neurofilament Medium Interaction
Signaling changes that occur in the striatum following the loss of dopamine neurons in the Parkinson disease (PD) are poorly understood. While increases in the activity of kinases and decreases in the activity of phosphatases have been observed, the specific consequences of these changes are less well understood. Phosphatases, such as protein phosphatase 1 (PP1), are highly promiscuous and obtain substrate selectivity via targeting proteins. Spinophilin is the major PP1-targeting protein enriched in the postsynaptic density of striatal dendritic spines. Spinophilin association with PP1 is increased concurrent with decreases in PP1 activity in an animal model of PD. Using proteomic-based approaches, we observed dopamine depletion-induced decreases in spinophilin binding to multiple protein classes in the striatum. Specifically, there was a decrease in the association of spinophilin with neurofilament medium (NF-M) in dopamine-depleted striatum. Using a heterologous cell line, we determined that spinophilin binding to NF-M required overexpression of the catalytic subunit of protein kinase A and was decreased by cyclin-dependent protein kinase 5. Functionally, we demonstrate that spinophilin can decrease NF-M phosphorylation. Our data determine mechanisms that regulate, and putative consequences of, pathological changes in the association of spinophilin with NF-M that are observed in animal models of PD
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