| 1. |
- Löfgren, Kajsa, et al.
(författare)
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Involvement of glypican-1 autoprocessing in scrapie infection
- 2008
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Ingår i: European Journal of Neuroscience. - : Wiley. - 1460-9568 .- 0953-816X. ; 28:5, s. 964-972
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Tidskriftsartikel (refereegranskat)abstract
- The copper-binding cellular prion protein (PrPC) and the heparan sulphate (HS)-containing proteoglycan glypican-1 (Gpc-1) can both be attached to lipid rafts via their glycosylphosphatidylinositol anchors, and copper ions stimulate their cointernalization from the cell surface to endosomes. The prion protein controls cointernalization and delivers copper necessary for S-nitrosylation of conserved cysteines in the Gpc-1 core protein. Later, during recycling through endosomal compartments, nitric oxide can be released from the S-nitroso groups and catalyses deaminative degradation and release of the HS substituents. Here, by using confocal immunofluorescence microscopy, we show that normal PrPC and Gpc-1 colocalize inside GT1-1 cells. However, in scrapie-infected cells (ScGT1-1), Gpc-1 protein remained at the cell surface separate from the cellular prion protein. Scrapie infection stimulated Gpc-1 autoprocessing and the generated HS degradation products colocalized with intracellular aggregates of the disease-related scrapie prion protein isoform (PrPSc). Coimmunoprecipitation experiments demonstrated an association between Gpc-1 and PrPC in uninfected cells, and between HS degradation products and PrPSc in infected cells. Silencing of Gpc-1 expression or prevention of Gpc-1 autoprocessing elevated the levels of intracellular PrPSc aggregates in infected cells. These results suggest a role for Gpc-1 autoprocessing in the clearance of PrPSc from infected cells.
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| 2. |
- Zora, Hatice, et al.
(författare)
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Concurrent affective and linguistic prosody with the same emotional valence elicits a late positive ERP response
- 2020
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Ingår i: European Journal of Neuroscience. - : Wiley. - 0953-816X .- 1460-9568. ; 51, s. 2236-2249
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Tidskriftsartikel (refereegranskat)abstract
- Change in linguistic prosody generates a mismatch negativity response (MMN), indicating neural representation of linguistic prosody, while change in affective prosody generates a positive response (P3a), reflecting its motivational salience. However, the neural response to concurrent affective and linguistic prosody is unknown. The present paper investigates the integration of these two prosodic features in the brain by examining the neural response to separate and concurrent processing by electroencephalography (EEG). A spoken pair of Swedish words-['fa:s epsilon n] phase and ['fa:s epsilon n] damn-that differed in emotional semantics due to linguistic prosody was presented to 16 subjects in an angry and neutral affective prosody using a passive auditory oddball paradigm. Acoustically matched pseudowords['va:s epsilon m] and ['va:s epsilon m]-were used as controls. Following the constructionist concept of emotions, accentuating the conceptualization of emotions based on language, it was hypothesized that concurrent affective and linguistic prosody with the same valence-angry ['fa:s epsilon n] damn-would elicit a unique late EEG signature, reflecting the temporal integration of affective voice with emotional semantics of prosodic origin. In accordance, linguistic prosody elicited an MMN at 300-350 ms, and affective prosody evoked a P3a at 350-400 ms, irrespective of semantics. Beyond these responses, concurrent affective and linguistic prosody evoked a late positive component (LPC) at 820-870 ms in frontal areas, indicating the conceptualization of affective prosody based on linguistic prosody. This study provides evidence that the brain does not only distinguish between these two functions of prosody but also integrates them based on language and experience.
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