Critical significance of the region between Helix 1 and 2 for efficient dominant-negative inhibition by conversion-incompetent prion protein.
Prion diseases are fatal infectious neurodegenerative disorders in man and animals associated with the accumulation of the pathogenic isoform PrP(Sc) of the host-encoded prion protein (PrP(c)). A profound conformational change of PrP(c) underlies formation of PrP(Sc) and prion propagation involves c...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2013-01-01
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| Series: | PLoS Pathogens |
| Online Access: | http://europepmc.org/articles/PMC3694865?pdf=render |
| _version_ | 1818037277299834880 |
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| author | Yuzuru Taguchi Arla M A Mistica Tetsuyuki Kitamoto Hermann M Schätzl |
| author_facet | Yuzuru Taguchi Arla M A Mistica Tetsuyuki Kitamoto Hermann M Schätzl |
| author_sort | Yuzuru Taguchi |
| collection | DOAJ |
| description | Prion diseases are fatal infectious neurodegenerative disorders in man and animals associated with the accumulation of the pathogenic isoform PrP(Sc) of the host-encoded prion protein (PrP(c)). A profound conformational change of PrP(c) underlies formation of PrP(Sc) and prion propagation involves conversion of PrP(c) substrate by direct interaction with PrP(Sc) template. Identifying the interfaces and modalities of inter-molecular interactions of PrPs will highly advance our understanding of prion propagation in particular and of prion-like mechanisms in general. To identify the region critical for inter-molecular interactions of PrP, we exploited here dominant-negative inhibition (DNI) effects of conversion-incompetent, internally-deleted PrP (ΔPrP) on co-expressed conversion-competent PrP. We created a series of ΔPrPs with different lengths of deletions in the region between first and second α-helix (H1∼H2) which was recently postulated to be of importance in prion species barrier and PrP fibril formation. As previously reported, ΔPrPs uniformly exhibited aberrant properties including detergent insolubility, limited protease digestion resistance, high-mannose type N-linked glycans, and intracellular localization. Although formerly controversial, we demonstrate here that ΔPrPs have a GPI anchor attached. Surprisingly, despite very similar biochemical and cell-biological properties, DNI efficiencies of ΔPrPs varied significantly, dependant on location and inversely correlated with the size of deletion. This data demonstrates that H1∼H2 and the region C-terminal to it are critically important for efficient DNI. It also suggests that this region is involved in PrP-PrP interaction and conversion of PrP(C) into PrP(Sc). To reconcile the paradox of how an intracellular PrP can exert DNI, we demonstrate that ΔPrPs are subject to both proteasomal and lysosomal/autophagic degradation pathways. Using autophagy pathways ΔPrPs obtain access to the locale of prion conversion and PrP(Sc) recycling and can exert DNI there. This shows that the intracellular trafficking of PrPs is more complex than previously anticipated. |
| first_indexed | 2024-12-10T07:24:17Z |
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| id | doaj.art-be48a63727cf439dbb7bba407dea9efd |
| institution | Directory Open Access Journal |
| issn | 1553-7366 1553-7374 |
| language | English |
| last_indexed | 2024-12-10T07:24:17Z |
| publishDate | 2013-01-01 |
| publisher | Public Library of Science (PLoS) |
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| series | PLoS Pathogens |
| spelling | doaj.art-be48a63727cf439dbb7bba407dea9efd2022-12-22T01:57:45ZengPublic Library of Science (PLoS)PLoS Pathogens1553-73661553-73742013-01-0196e100346610.1371/journal.ppat.1003466Critical significance of the region between Helix 1 and 2 for efficient dominant-negative inhibition by conversion-incompetent prion protein.Yuzuru TaguchiArla M A MisticaTetsuyuki KitamotoHermann M SchätzlPrion diseases are fatal infectious neurodegenerative disorders in man and animals associated with the accumulation of the pathogenic isoform PrP(Sc) of the host-encoded prion protein (PrP(c)). A profound conformational change of PrP(c) underlies formation of PrP(Sc) and prion propagation involves conversion of PrP(c) substrate by direct interaction with PrP(Sc) template. Identifying the interfaces and modalities of inter-molecular interactions of PrPs will highly advance our understanding of prion propagation in particular and of prion-like mechanisms in general. To identify the region critical for inter-molecular interactions of PrP, we exploited here dominant-negative inhibition (DNI) effects of conversion-incompetent, internally-deleted PrP (ΔPrP) on co-expressed conversion-competent PrP. We created a series of ΔPrPs with different lengths of deletions in the region between first and second α-helix (H1∼H2) which was recently postulated to be of importance in prion species barrier and PrP fibril formation. As previously reported, ΔPrPs uniformly exhibited aberrant properties including detergent insolubility, limited protease digestion resistance, high-mannose type N-linked glycans, and intracellular localization. Although formerly controversial, we demonstrate here that ΔPrPs have a GPI anchor attached. Surprisingly, despite very similar biochemical and cell-biological properties, DNI efficiencies of ΔPrPs varied significantly, dependant on location and inversely correlated with the size of deletion. This data demonstrates that H1∼H2 and the region C-terminal to it are critically important for efficient DNI. It also suggests that this region is involved in PrP-PrP interaction and conversion of PrP(C) into PrP(Sc). To reconcile the paradox of how an intracellular PrP can exert DNI, we demonstrate that ΔPrPs are subject to both proteasomal and lysosomal/autophagic degradation pathways. Using autophagy pathways ΔPrPs obtain access to the locale of prion conversion and PrP(Sc) recycling and can exert DNI there. This shows that the intracellular trafficking of PrPs is more complex than previously anticipated.http://europepmc.org/articles/PMC3694865?pdf=render |
| spellingShingle | Yuzuru Taguchi Arla M A Mistica Tetsuyuki Kitamoto Hermann M Schätzl Critical significance of the region between Helix 1 and 2 for efficient dominant-negative inhibition by conversion-incompetent prion protein. PLoS Pathogens |
| title | Critical significance of the region between Helix 1 and 2 for efficient dominant-negative inhibition by conversion-incompetent prion protein. |
| title_full | Critical significance of the region between Helix 1 and 2 for efficient dominant-negative inhibition by conversion-incompetent prion protein. |
| title_fullStr | Critical significance of the region between Helix 1 and 2 for efficient dominant-negative inhibition by conversion-incompetent prion protein. |
| title_full_unstemmed | Critical significance of the region between Helix 1 and 2 for efficient dominant-negative inhibition by conversion-incompetent prion protein. |
| title_short | Critical significance of the region between Helix 1 and 2 for efficient dominant-negative inhibition by conversion-incompetent prion protein. |
| title_sort | critical significance of the region between helix 1 and 2 for efficient dominant negative inhibition by conversion incompetent prion protein |
| url | http://europepmc.org/articles/PMC3694865?pdf=render |
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