RESUMEN

One of the most commonly replicated results in the research area of recidivism risk assessment is the superiority of structured and standardized prediction methods in comparison to unstructured, subjective, intuitive, or impressionistic clinical judgments. However, the quality of evidence supporting this conclusion is partly still controversially discussed because studies including direct comparisons of the predictive accuracy of unstructured and structured risk assessment methods have been relatively rarely conducted. Therefore, we examined in the present study retrospectively N = 416 expert witness reports written about individuals convicted of violent and/or sexual offenses in Germany between 1999 and 2015. The predictive accuracy of different methodological approaches of risk assessment (subjective clinical [i.e., unstructured clinical judgment; UCJ], structured professional judgment [SPJ], actuarial risk assessment instruments [ARAIs], and combinations of ARAIs-/SPJ-based risk assessments) was compared by analyzing the actual reoffenses according to the Federal Central Register (average follow-up period M = 7.08 years). In accordance with previously published results, the results indicated a higher predictive accuracy for structured compared to unstructured risk assessment approaches for the prediction of general, violent, and sexual recidivism. Taken together, the findings underline the limited accuracy of UCJs and provided further support for the use of structured and standardized risk assessment procedures in the area of crime and delinquency. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Asunto(s)

Reincidencia , Delitos Sexuales , Humanos , Estudios Retrospectivos , Reproducibilidad de los Resultados , Conducta Sexual , Medición de Riesgo/métodos

RESUMEN

Several neurological diseases, including Parkinson disease and dementia with Lewy bodies, are characterized by the accumulation of alpha-synuclein phosphorylated at Ser-129 (p-Ser-129). The kinase or kinases responsible for this phosphorylation have been the subject of intense investigation. Here we submit evidence that polo-like kinase 2 (PLK2, also known as serum-inducible kinase or SNK) is a principle contributor to alpha-synuclein phosphorylation at Ser-129 in neurons. PLK2 directly phosphorylates alpha-synuclein at Ser-129 in an in vitro biochemical assay. Inhibitors of PLK kinases inhibited alpha-synuclein phosphorylation both in primary cortical cell cultures and in mouse brain in vivo. Finally, specific knockdown of PLK2 expression by transduction with short hairpin RNA constructs or by knock-out of the plk2 gene reduced p-Ser-129 levels. These results indicate that PLK2 plays a critical role in alpha-synuclein phosphorylation in central nervous system.

Asunto(s)

Sistema Nervioso Central/metabolismo , Proteínas Quinasas/metabolismo , Serina/metabolismo , alfa-Sinucleína/metabolismo , Animales , Secuencia de Bases , Línea Celular , Sistema Nervioso Central/enzimología , Cartilla de ADN , Ensayo de Inmunoadsorción Enzimática , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fosforilación , Proteínas Serina-Treonina Quinasas , Interferencia de ARN , alfa-Sinucleína/química

RESUMEN

The cellular prion protein (PrP(c)) is a glycosyl-phosphatidylinositol (GPI)-anchored protein trafficking in the secretory and endocytic pathway and localized mainly at the plasma membrane. Conversion of PrP(c) into its pathogenic isoform PrP(Sc) is associated with pathogenesis and transmission of prion diseases. Intramolecular cleavage in the middle, the extreme C-terminal part or within the GPI anchor and shedding of PrP(c) modulate this conversion process by reducing the substrate for prion formation. These phenomena provide similarities with the processing of amyloid precursor protein in Alzheimer's disease. Sorting nexins are a family of proteins with important functions in protein trafficking. In this study, we investigated the role of the newly described sorting nexin 33 (SNX33) in trafficking and processing of PrP(c). We found that overexpression of SNX33 in neuronal and non-neuronal cell lines resulted in increased shedding of full-length PrP(c) from the plasma membrane and modulated the rate of PrP(c) endocytosis. This was paralleled by reduction of PrP(Sc) formation in persistently and newly infected cells. Using deletion mutants, we demonstrate that production of PrP fragment N1 is not influenced by SNX33. Our data provide new insights into the cellular mechanisms of PrP(c) shedding and show how this can affect cellular PrP(Sc) conversion.

Asunto(s)

Proteínas Portadoras/metabolismo , Proteínas Portadoras/fisiología , Priones/química , Proteínas de Transporte Vesicular/metabolismo , Proteínas de Transporte Vesicular/fisiología , Amiloide/química , Animales , Biotinilación , Encéfalo/metabolismo , Proteínas Portadoras/química , Línea Celular , Línea Celular Tumoral , Endocitosis , Eliminación de Gen , Humanos , Ratones , Modelos Biológicos , Enfermedades por Prión/metabolismo , Priones/metabolismo , Transporte de Proteínas , Nexinas de Clasificación , Proteínas de Transporte Vesicular/química

RESUMEN

Ectodomain shedding of the amyloid precursor protein (APP) by the two proteases alpha- and beta-secretase is a key regulatory event in the generation of the Alzheimer disease amyloid beta peptide (Abeta). beta-Secretase catalyzes the first step in Abeta generation, whereas alpha-secretase cleaves within the Abeta domain, prevents Abeta generation, and generates a secreted form of APP with neuroprotective properties. At present, little is known about the cellular mechanisms that control APP alpha-secretase cleavage and Abeta generation. To explore the contributory pathways, we carried out an expression cloning screen. We identified a novel member of the sorting nexin (SNX) family of endosomal trafficking proteins, called SNX33, as a new activator of APP alpha-secretase cleavage. SNX33 is a homolog of SNX9 and was found to be a ubiquitously expressed phosphoprotein. Exogenous expression of SNX33 in cultured cells increased APP alpha-secretase cleavage 4-fold but surprisingly had little effect on beta-secretase cleavage. This effect was similar to the expression of the dominant negative dynamin-1 mutant K44A. SNX33 bound the endocytic GTPase dynamin and reduced the rate of APP endocytosis in a dynamin-dependent manner. This led to an increase of APP at the plasma membrane, where alpha-secretase cleavage mostly occurs. In summary, our study identifies SNX33 as a new endocytic protein, which modulates APP endocytosis and APP alpha-secretase cleavage, and demonstrates that the rate of APP endocytosis is a major control factor for APP alpha-secretase cleavage.

Asunto(s)

Secretasas de la Proteína Precursora del Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Proteínas Portadoras/metabolismo , Endocitosis , Proteínas de Transporte Vesicular/metabolismo , Secuencia de Aminoácidos , Animales , Animales Modificados Genéticamente , Caenorhabditis elegans , Proteínas Portadoras/química , Línea Celular , Chlorocebus aethiops , Clonación Molecular , Dinaminas/metabolismo , Regulación Enzimológica de la Expresión Génica , Humanos , Ratones , Datos de Secuencia Molecular , Fosforilación , Unión Proteica , Transporte de Proteínas , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Nexinas de Clasificación , Transferrina/metabolismo , Proteínas de Transporte Vesicular/química

RESUMEN

Ectodomain shedding of the amyloid precursor protein (APP) is a key regulatory step in the generation of the amyloid beta peptide (Abeta), which is thought to provoke the pathogenesis of Alzheimer's disease. To better understand the cellular processes that regulate ectodomain shedding of APP we used human embryonic kidney 293 cells and applied a sib-selection expression cloning approach. In addition to a known activator of APP shedding -- protein kinase A -- the following cDNAs were identified: the endocytic proteins endophilin A1 and A3, the metabotropic glutamate receptor 3 (mGluR3), palmitoyl-protein thioesterase 1 (PPT1), Numb-like and the kinase MEKK2. Endophilins A1 and A3, as well as mGluR3 activated APP shedding relatively specifically. They had little or no effect on the shedding of the unrelated membrane proteins TNF receptor 2 and P-selectin glycoprotein ligand-1. In contrast, MEKK2 and PKA also increased shedding of TNF receptor 2, suggesting that these kinases contribute to a general program regulating ectodomain shedding. The strongest activator of APP shedding, endophilin A3, reduced the rate of APP endocytosis and specifically increased APP shedding by the protease alpha-secretase, as measured in an antibody uptake assay and by immunoblot analysis. This suggests that endophilin A3 is a novel modulator of APP trafficking affecting access of APP to alpha-secretase. In summary, this study shows that expression cloning is a suitable way to identify proteins controlling ectodomain shedding of membrane proteins.

Asunto(s)

Precursor de Proteína beta-Amiloide/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Expresión Génica/fisiología , Aciltransferasas/metabolismo , Precursor de Proteína beta-Amiloide/genética , Western Blotting/métodos , Línea Celular , Clonación Molecular/métodos , Proteína Quinasa Tipo II Dependiente de AMP Cíclico , Endocitosis/fisiología , Activación Enzimática/fisiología , Biblioteca de Genes , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Glicoproteínas de Membrana/metabolismo , Procesamiento Proteico-Postraduccional , Transporte de Proteínas/fisiología , Receptores Tipo II del Factor de Necrosis Tumoral/metabolismo , Factores de Tiempo , Transfección/métodos , Transferrina/metabolismo

RESUMEN

Ectodomain shedding of the amyloid precursor protein (APP) is a key regulatory step in the generation of the Alzheimer disease amyloid beta peptide (Abeta). The molecular mechanisms underlying the control of APP shedding remain little understood but are in part dependent on the low density lipoprotein receptor-related protein (LRP), which is involved in APP endocytosis. Here, we show that the APP homolog APLP1 (amyloid precursor-like protein 1) influences APP shedding. In human embryonic kidney 293 cells expression of APLP1 strongly activated APP shedding by alpha-secretase and slightly reduced beta-secretase cleavage. As revealed by domain deletion analysis, the increase in APP shedding required the NPTY amino acid motif within the cytoplasmic domain of APLP1. This motif is conserved in APP and is essential for the endocytosis of APP and APLP1. Unrelated membrane proteins containing similar endocytic motifs did not affect APP shedding, showing that the increase in APP shedding was specific to APLP1. In LRP-deficient cells APLP1 no longer induced APP shedding, suggesting that in wild-type cells APLP1 interferes with the LRP-dependent endocytosis of APP and there by increases APP alpha-cleavage. In fact, an antibody uptake assay revealed that expression of APLP1 reduced the rate of APP endocytosis. In summary, our study provides a novel mechanism for APP shedding, in which APLP1 affects the endocytosis of APP and makes more APP available for alpha-secretase cleavage.

Asunto(s)

Precursor de Proteína beta-Amiloide/química , Secuencias de Aminoácidos , Secretasas de la Proteína Precursora del Amiloide , Precursor de Proteína beta-Amiloide/fisiología , Animales , Ácido Aspártico Endopeptidasas , Western Blotting , Células CHO , Células COS , Línea Celular , Chlorocebus aethiops , Cricetinae , Citoplasma/metabolismo , Endocitosis , Endopeptidasas/metabolismo , Eliminación de Gen , Genes Reporteros , Vectores Genéticos , Humanos , Inmunoprecipitación , Microscopía Fluorescente , Modelos Genéticos , Péptidos/química , Plásmidos/metabolismo , Estructura Terciaria de Proteína , Proteínas Recombinantes de Fusión/química , Factores de Tiempo , Transfección

RESUMEN

The aspartyl protease BACE1 has a pivotal role in the pathogenesis of Alzheimer's disease. Recently, it was shown that in Alzheimer's disease patients, BACE1 levels were elevated although mRNA levels were not changed compared with controls. Here, we demonstrate that the 5'-untranslated region (5'UTR) of BACE1 controls the rate of BACE1 translation. In the presence of the 5'UTR, we observed more than 90% reduction of BACE1 protein levels in HEK293, COS7 and H4 cells, and a similar reduction of BACE1 activity in vitro. mRNA levels were not affected, demonstrating that the 5'UTR repressed the translation but not the transcription of BACE1. The 3'UTR did not affect BACE1 expression. An extensive mutagenesis analysis predicts that the GC-rich region of the 5'UTR forms a constitutive translation barrier, which may prevent the ribosome from efficiently translating the BACE1 mRNA. Our data therefore demonstrate translational repression as a new mechanism controlling BACE1 expression.

Asunto(s)

Regiones no Traducidas 5'/genética , Enfermedad de Alzheimer/enzimología , Ácido Aspártico Endopeptidasas/genética , Regulación Enzimológica de la Expresión Génica , Enfermedad de Alzheimer/genética , Secretasas de la Proteína Precursora del Amiloide , Animales , Ácido Aspártico Endopeptidasas/análisis , Ácido Aspártico Endopeptidasas/biosíntesis , Secuencia de Bases , Regulación hacia Abajo , Endopeptidasas , Humanos , Datos de Secuencia Molecular , Mutación , Sistemas de Lectura Abierta/genética , Biosíntesis de Proteínas/genética , ARN Mensajero/análisis , ARN Mensajero/metabolismo

RESUMEN

The Bacillus subtilis sigma(W) regulon is induced by different stresses such as alkaline shock, salt shock, phage infection and certain antibiotics that affect cell wall biosynthesis. The activity of the alternative, extracytoplasmic function (ECF) sigma factor sigma(W) is modulated by a specific anti-sigma factor (RsiW or YbbM) encoded by the rsiW (ybbM) gene located immediately downstream of sigW. The RsiW membrane topology was determined, and a specific reporter system for RsiW function was constructed. Experiments using the yeast two-hybrid system suggested a direct interaction of sigma(W) with the cytoplasmic part of RsiW. Analysis of truncated forms of the RsiW protein revealed that sigma(W) induction by alkaline shock is dependent on both the transmembrane and the extracytoplasmic domain of RsiW. Western blot and pulse-chase experiments demonstrated degradation of RsiW after an alkaline shock. A B. subtilis mutant strain deleted for the Escherichia coli yaeL orthologue yluC, encoding a transmembrane protease, was defective in inducing a sigma(W)-controlled promoter after alkaline shock and accumulated a membrane-bound truncated form of RsiW, suggesting that the activity of sigma(W) is controlled by the proteolysis of RsiW by at least two different proteolytic steps.

Asunto(s)

Bacillus subtilis/metabolismo , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Factor sigma/antagonistas & inhibidores , Transcripción Genética , Fusión Artificial Génica , Proteínas Bacterianas/genética , Western Blotting , Eliminación de Gen , Genes Reporteros , Concentración de Iones de Hidrógeno , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Mutación , Péptido Hidrolasas/genética , Péptido Hidrolasas/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Regulón , Eliminación de Secuencia , Técnicas del Sistema de Dos Híbridos , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismo