Publications (39)319.91 Total impact
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Dataset: Table of SPP-interacting peptides
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Article: Interactome analyses of mature γ-secretase complexes reveals distinct molecular environments of presenilin (PS) paralogs and preferential binding of signal peptide peptidase to PS2.
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ABSTRACT: γ-Secretase plays a pivotal role in the production of neurotoxic amyloid β-peptides (Aβ) in Alzheimer disease (AD) and consists of a heterotetrameric core complex that includes the aspartyl intramembrane protease presenilin (PS). The human genome codes for two presenilin paralogs. To understand the causes for distinct phenotypes of PS paralog deficient mice and elucidate whether PS mutations associated with early-onset AD affect the molecular environment of mature γ-secretase complexes, quantitative interactome comparisons were undertaken. Brains of mice engineered to express wild-type or mutant PS1, or HEK293 cells stably expressing PS paralogs with N-terminal tandem-affinity purification (TAP) tags served as biological source materials. The analyses revealed novel interactions of the γ-secretase core complex with a molecular machinery that targets and fuses synaptic vesicles to cellular membranes and with the H+-transporting lysosomal ATPase macro-complex but uncovered no differences in the interactomes of wild-type and mutant PS1. The catenin/cadherin network was almost exclusively found associated with PS1. Another intramembrane protease, signal peptide peptidase (SPP), predominantly co-purified with PS2-containing γ-secretase complexes and was observed to influence Aβ production.Journal of Biological Chemistry 04/2013; · 4.77 Impact Factor -
Article: The ZIP-prion connection.
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ABSTRACT: The evolutionary origins of vertebrate prion genes had remained elusive until recently when multiple lines of evidence converged to the proposition that members of the prion gene family represent an ancient branch of a larger family of ZIP metal ion transporters. ( 1) A follow-up investigation which explored the mechanism of evolution in more detail led to the surprising conclusion that the emergence of the prion founder gene likely involved the reverse transcription of a spliced transcript of a LIV-1 ZIP predecessor gene. ( 2) The objective of this perspective is to discuss the possible significance of this reunion of ZIP and prion gene subfamilies for understanding the biology of the prion protein in health and disease. While a recent review article broadly introduced this area of research, ( 3) the emphasis here is to comment on some of the more pertinent concepts, experimental paradigms, ongoing developments and challenges.Prion 09/2012; 6(4):317-21. · 2.85 Impact Factor -
Article: LIV-1 ZIP ectodomain shedding in prion-infected mice resembles cellular response to transition metal starvation.
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ABSTRACT: We recently documented the co-purification of members of the LIV-1 subfamily of ZIP (Zrt-, Irt-like Protein) zinc transporters (LZTs) with the cellular prion protein (PrP(C)) and, subsequently, established that the prion gene family descended from an ancestral LZT gene. Here, we begin to address whether the study of LZTs can shed light on the biology of prion proteins in health and disease. Starting from an observation of an abnormal LZT immunoreactive band in prion-infected mice, subsequent cell biological analyses uncovered a surprisingly coordinated biology of ZIP10 (an LZT member) and prion proteins that involves alterations to N-glycosylation and endoproteolysis in response to manipulations to the extracellular divalent cation milieu. Starving cells of manganese or zinc, but not copper, causes shedding of the N1 fragment of PrP(C) and of the ectodomain of ZIP10. For ZIP10, this posttranslational biology is influenced by an interaction between its PrP-like ectodomain and a conserved metal coordination site within its C-terminal multi-spanning transmembrane domain. The transition metal starvation-induced cleavage of ZIP10 can be differentiated by an immature N-glycosylation signature from a constitutive cleavage targeting the same site. Data from this work provide a first glimpse into a hitherto neglected molecular biology that ties PrP to its LZT cousins and suggest that manganese or zinc starvation may contribute to the etiology of prion disease in mice.Journal of Molecular Biology 06/2012; 422(4):556-74. · 4.00 Impact Factor -
Article: Vigilin interacts with Signal Peptide Peptidase.
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ABSTRACT: BACKGROUND: Signal peptide peptidase (SPP), a member of the presenilin-like intra-membrane cleaving aspartyl protease family, migrates on Blue Native (BN) gels as 100 kDa, 200 kDa and 450 kDa species. SPP has recently been implicated in other non-proteolytic functions such as retro-translocation of MHC Class I molecules and binding of misfolded proteins in the endoplasmic reticulum (ER). These high molecular weight SPP complexes might contain additional proteins that regulate the proteolytic activity of SPP or support its non-catalytic functions. RESULTS: In this study, an unbiased iTRAQ-labeling mass spectrometry approach was used to identify SPP-interacting proteins. We found that vigilin, a ubiquitous multi-KH domain containing cytoplasmic protein involved in RNA binding and protein translation control, selectively enriched with SPP. Vigilin interacted with SPP and both proteins co-localized in restricted intracellular domains near the ER, biochemically co-fractionated and were part of the same 450 kDa complex on BN gels. However, vigilin does not alter the protease activity of SPP, suggesting that the SPP-vigilin interaction might be involved in the non-proteolytic functions of SPP. CONCLUSIONS: We have identified and validated vigilin as a novel interacting partner of SPP that could play an important role in the non-proteolytic functions of SPP. This data adds further weight to the idea that intramembrane-cleaving aspartyl proteases, such as presenilin and SPPs, could have other functions besides the proteolysis of short membrane stubs.Proteome Science 05/2012; 10(1):33. · 2.33 Impact Factor -
Article: Time-controlled transcardiac perfusion crosslinking for in vivo interactome studies.
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ABSTRACT: The time-controlled transcardiac perfusion crosslinking (tcTPC) method differs from conventional perfusion fixation in that the crosslinking reagent is administered throughout the circulatory system for only a relatively short period of time, thereby allowing limited crosslinking to occur. Bait protein complexes are isolated by affinity capture (AC) under stringent conditions and are recovered from the AC matrix by acidic elution. Affinity-purified proteins are reduced, alkylated, and digested with a specific endoproteinase, such as trypsin. Subsequently, peptides are isotopically labeled, separated by reversed-phase chromatography and analyzed by quantitative tandem mass spectrometry (MS/MS). The proteins crosslinked to the bait protein during tcTPC are identified by database searches with conventional protein identification software. The tcTPC strategy offers unique advantages over alternative approaches for studying a subset of protein complexes which require a particular environment for their structural integrity, such as membrane protein complexes that are notorious for their tendency to dissociate upon detergent solubilization. The sensitivity and utility of this method are influenced by the spatial distribution of chemical groups within the bait protein complexes that can engage in productive crosslinks.Methods in molecular biology (Clifton, N.J.) 01/2012; 803:231-46. -
Article: PrionHome: a database of prions and other sequences relevant to prion phenomena.
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ABSTRACT: Prions are units of propagation of an altered state of a protein or proteins; prions can propagate from organism to organism, through cooption of other protein copies. Prions contain no necessary nucleic acids, and are important both as both pathogenic agents, and as a potential force in epigenetic phenomena. The original prions were derived from a misfolded form of the mammalian Prion Protein PrP. Infection by these prions causes neurodegenerative diseases. Other prions cause non-Mendelian inheritance in budding yeast, and sometimes act as diseases of yeast. We report the bioinformatic construction of the PrionHome, a database of >2000 prion-related sequences. The data was collated from various public and private resources and filtered for redundancy. The data was then processed according to a transparent classification system of prionogenic sequences (i.e., sequences that can make prions), prionoids (i.e., proteins that propagate like prions between individual cells), and other prion-related phenomena. There are eight PrionHome classifications for sequences. The first four classifications are derived from experimental observations: prionogenic sequences, prionoids, other prion-related phenomena, and prion interactors. The second four classifications are derived from sequence analysis: orthologs, paralogs, pseudogenes, and candidate-prionogenic sequences. Database entries list: supporting information for PrionHome classifications, prion-determinant areas (where relevant), and disordered and compositionally-biased regions. Also included are literature references for the PrionHome classifications, transcripts and genomic coordinates, and structural data (including comparative models made for the PrionHome from manually curated alignments). We provide database usage examples for both vertebrate and fungal prion contexts. Using the database data, we have performed a detailed analysis of the compositional biases in known budding-yeast prionogenic sequences, showing that the only abundant bias pattern is for asparagine bias with subsidiary serine bias. We anticipate that this database will be a useful experimental aid and reference resource. It is freely available at: http://libaio.biol.mcgill.ca/prion.PLoS ONE 01/2012; 7(2):e31785. · 4.09 Impact Factor -
Article: Down-regulation of Shadoo in prion infections traces a pre-clinical event inversely related to PrP(Sc) accumulation.
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ABSTRACT: During prion infections of the central nervous system (CNS) the cellular prion protein, PrP(C), is templated to a conformationally distinct form, PrP(Sc). Recent studies have demonstrated that the Sprn gene encodes a GPI-linked glycoprotein Shadoo (Sho), which localizes to a similar membrane environment as PrP(C) and is reduced in the brains of rodents with terminal prion disease. Here, analyses of prion-infected mice revealed that down-regulation of Sho protein was not related to Sprn mRNA abundance at any stage in prion infection. Down-regulation was robust upon propagation of a variety of prion strains in Prnp(a) and Prnp(b) mice, with the exception of the mouse-adapted BSE strain 301 V. In addition, Sho encoded by a TgSprn transgene was down-regulated to the same extent as endogenous Sho. Reduced Sho levels were not seen in a tauopathy, in chemically induced spongiform degeneration or in transgenic mice expressing the extracellular ADan amyloid peptide of familial Danish dementia. Insofar as prion-infected Prnp hemizygous mice exhibited accumulation of PrP(Sc) and down-regulation of Sho hundreds of days prior to onset of neurologic symptoms, Sho depletion can be excluded as an important trigger for clinical disease or as a simple consequence of neuronal damage. These studies instead define a disease-specific effect, and we hypothesize that membrane-associated Sho comprises a bystander substrate for processes degrading PrP(Sc). Thus, while protease-resistant PrP detected by in vitro digestion allows post mortem diagnosis, decreased levels of endogenous Sho may trace an early response to PrP(Sc) accumulation that operates in the CNS in vivo. This cellular response may offer new insights into the homeostatic mechanisms involved in detection and clearance of the misfolded proteins that drive prion disease pathogenesis.PLoS Pathogens 11/2011; 7(11):e1002391. · 9.13 Impact Factor -
Article: Choice of biological source material supersedes oxidative stress in its influence on DJ-1 in vivo interactions with Hsp90.
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ABSTRACT: DJ-1 is a small but relatively abundant protein of unknown function that may undergo stress-dependent cellular translocation and has been implicated in both neurodegenerative diseases and cancer. As such, DJ-1 may be an excellent study object to elucidate the relative influence of the cellular context on its interactome and for exploring whether acute exposure to oxidative stressors alters its molecular environment. Using quantitative mass spectrometry, we conducted comparative DJ-1 interactome analyses from in vivo cross-linked brains or livers and from hydrogen peroxide-treated or naïve embryonic stem cells. The analysis identified a subset of glycolytic enzymes, heat shock proteins 70 and 90, and peroxiredoxins as interactors of DJ-1. Consistent with a role of DJ-1 in Hsp90 chaperone biology, we document destabilization of Hsp90 clients in DJ-1 knockout cells. We further demonstrate the existence of a C106 sulfinic acid modification within DJ-1 and thereby establish that this previously inferred modification also exists in vivo. Our data suggest that caution has to be exerted in interpreting interactome data obtained from a single biological source material and identify a role of DJ-1 as an oxidative stress sensor and partner of a molecular machinery notorious for its involvement in cell fate decisions.Journal of Proteome Research 08/2011; 10(10):4388-404. · 5.11 Impact Factor -
Article: Evidence for retrogene origins of the prion gene family.
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ABSTRACT: The evolutionary origin of prion genes, only known to exist in the vertebrate lineage, had remained elusive until recently. Following a lead from interactome investigations of the murine prion protein, our previous bioinformatic analyses revealed the evolutionary descent of prion genes from an ancestral ZIP metal ion transporter. However, the molecular mechanism of evolution remained unexplored. Here we present a computational investigation of this question based on sequence, intron-exon, synteny and pseudogene analyses. Our data suggest that during the emergence of metazoa, a cysteine-flanked core domain was modularly inserted, or arose de novo, in a preexisting ZIP ancestor gene to generate a prion-like ectodomain in a subbranch of ZIP genes. Approximately a half-billion years later, a genomic insertion of a spliced transcript coding for such a prion-like ZIP ectodomain may have created the prion founder gene. We document that similar genomic insertions involving ZIP transcripts, and probably relying on retropositional elements, have indeed occurred more than once throughout evolution.PLoS ONE 01/2011; 6(10):e26800. · 4.09 Impact Factor -
Article: Family reunion--the ZIP/prion gene family.
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ABSTRACT: Prion diseases are fatal neurodegenerative diseases of humans and animals which, in addition to sporadic and familial modes of manifestation, can be acquired via an infectious route of propagation. In disease, the prion protein (PrP(C)) undergoes a structural transition to its disease-causing form (PrP(Sc)) with profoundly different physicochemical properties. Surprisingly, despite intense interest in the prion protein, its function in the context of other cellular activities has largely remained elusive. We recently employed quantitative mass spectrometry to characterize the interactome of the prion protein in a murine neuroblastoma cell line (N2a), an established cell model for prion replication. Extensive bioinformatic analyses subsequently established an evolutionary link between the prion gene family and the family of ZIP (Zrt-, Irt-like protein) metal ion transporters. More specifically, sequence alignments, structural threading data and multiple additional pieces of evidence placed a ZIP5/ZIP6/ZIP10-like ancestor gene at the root of the PrP gene family. In this review we examine the biology of prion proteins and ZIP transporters from the viewpoint of a shared phylogenetic origin. We summarize and compare available data that shed light on genetics, function, expression, signaling, post-translational modifications and metal binding preferences of PrP and ZIP family members. Finally, we explore data indicative of retropositional origins of the prion gene founder and discuss a possible function for the prion-like (PL) domain within ZIP transporters. While throughout the article emphasis is placed on ZIP proteins, the intent is to highlight connections between PrP and ZIP transporters and uncover promising directions for future research.Progress in Neurobiology 12/2010; 93(3):405-20. · 8.87 Impact Factor -
Article: Alzheimer's disease: Selectively tuning gamma-secretase.
Nature 09/2010; 467(7311):36-7. · 36.28 Impact Factor -
Article: Proteome-wide identification of mycobacterial pupylation targets.
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ABSTRACT: Mycobacteria use a unique system for covalently modifying proteins based on the conjugation of a small protein, referred to as prokaryotic ubiquitin-like protein (PUP). In this study, we report a proteome-wide analysis of endogenous pupylation targets in the model organism Mycobacterium smegmatis. On affinity capture, a total of 243 candidate pupylation targets were identified by two complementary proteomics approaches. For 41 of these protein targets, direct evidence for a total of 48 lysine-mediated pupylation acceptor sites was obtained by collision-induced dissociation spectra. For the majority of these pupylation targets (38 of 41), orthologous genes are found in the M. tuberculosis genome. Interestingly, approximately half of these proteins are involved in intermediary metabolism and respiration pathways. A considerable fraction of the remaining targets are involved in lipid metabolism, information pathways, and virulence, detoxification and adaptation. Approximately one-third of the genes encoding these targets are located in seven gene clusters, indicating functional linkages of mycobacterial pupylation targets. A comparison of the pupylome under different cell culture conditions indicates that substrate targeting for pupylation is rather dynamic.Molecular Systems Biology 07/2010; 6:386. · 8.63 Impact Factor -
Article: Wild-type Shadoo proteins convert to amyloid-like forms under native conditions.
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ABSTRACT: The cellular prion protein PrP(C) refolds into a beta-sheet enriched, infectivity-associated form called PrP(Sc). Shadoo (Sho) is a newly discovered glycoprotein that is also expressed in the adult brain. Wild type (wt) mouse Sho consists of an arginine-rich region, a hydrophobic central domain of five tandem A/LAAG amino acid repeats R1-R5 with similarity to the hydrophobic domain of PrP(C), and a C-terminal domain with one N-linked carbohydrate. As some alanine-rich proteins and PrP with a shortened C-terminal domain form amyloid we investigated conformational properties of wt Sho and polymorphic variants with insertion/deletions centered on R3. Recombinant mouse and sheep Sho converted to an amyloid-like form without recourse to chemical denaturation or acidification. For wt proteins this transition was marked by increased thioflavin T binding, Congo red staining, presence of fibrillar structures by electron microscopy, formation of sodium dodecyl sulfate-resistant complexes and the generation of a C-terminal proteinase K resistant core of 5-8 kDa. Variant Sho proteins differing within the R1-R5 region exhibited most but not all of these properties. Our studies define a proteinase K -resistant signature fragment for the amyloid fold of Sho and raise the question of a physiological role for this form of the wt protein.Journal of Neurochemistry 04/2010; 113(1):92-104. · 4.06 Impact Factor -
Article: Method for the affinity purification of covalently linked peptides following cyanogen bromide cleavage of proteins.
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ABSTRACT: The low resolution structure of a protein can sometimes be inferred from information about existing disulfide bridges or experimentally introduced chemical crosslinks. Frequently, this task involves enzymatic digestion of a protein followed by mass spectrometry-based identification of covalently linked peptides. To facilitate this task, we developed a method for the enrichment of covalently linked peptides following the chemical cleavage of a protein. The method capitalizes on the availability of homoserine lactone moieties at the C-termini of cyanogen bromide cleavage products which support selective conjugation of affinity tags. The availability of two C-termini within covalently linked peptides allows for the conjugation of two distinct affinity tags and thereby enables subsequent removal of unmodified peptides by tandem affinity chromatography. Here, we demonstrate the stepwise implementation of this method using a polyhistidine tag and a biotin tag for the selective two-step purification of covalently linked cyanogen bromide fragments from increasingly complex protein samples. The method is independent of the nature of the covalent bond, is adaptable to fully denaturing conditions, and requires only low picomole quantities of starting material.Analytical Chemistry 11/2009; 81(24):9885-95. · 5.86 Impact Factor -
Article: Interactome analyses identify ties of PrP and its mammalian paralogs to oligomannosidic N-glycans and endoplasmic reticulum-derived chaperones.
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ABSTRACT: The physiological environment which hosts the conformational conversion of the cellular prion protein (PrP(C)) to disease-associated isoforms has remained enigmatic. A quantitative investigation of the PrP(C) interactome was conducted in a cell culture model permissive to prion replication. To facilitate recognition of relevant interactors, the study was extended to Doppel (Prnd) and Shadoo (Sprn), two mammalian PrP(C) paralogs. Interestingly, this work not only established a similar physiological environment for the three prion protein family members in neuroblastoma cells, but also suggested direct interactions amongst them. Furthermore, multiple interactions between PrP(C) and the neural cell adhesion molecule, the laminin receptor precursor, Na/K ATPases and protein disulfide isomerases (PDI) were confirmed, thereby reconciling previously separate findings. Subsequent validation experiments established that interactions of PrP(C) with PDIs may extend beyond the endoplasmic reticulum and may play a hitherto unrecognized role in the accumulation of PrP(Sc). A simple hypothesis is presented which accounts for the majority of interactions observed in uninfected cells and suggests that PrP(C) organizes its molecular environment on account of its ability to bind to adhesion molecules harboring immunoglobulin-like domains, which in turn recognize oligomannose-bearing membrane proteins.PLoS Pathogens 10/2009; 5(10):e1000608. · 9.13 Impact Factor -
Article: Peptide separations by on-line MudPIT compared to isoelectric focusing in an off-gel format: application to a membrane-enriched fraction from C2C12 mouse skeletal muscle cells.
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ABSTRACT: High-resolution peptide separation is pivotal for successful shotgun proteomics. The need for capable techniques propels invention and improvement of ever more sophisticated approaches. Recently, Agilent Technologies has introduced the OFFGEL fractionator, which conducts peptide separation by isoelectric focusing in an off-gel setup. This platform has been shown to accomplish high resolution of peptides for diverse sample types, yielding valuable advantages over comparable separation techniques. In this study, we deliver the first comparison of the newly emerging OFFGEL approach to the well-established on-line MudPIT platform. Samples from a membrane-enriched fraction isolated from murine C2C12 cells were subjected to replicate analysis by OFFGEL (12 fractions, pH 3-10) followed by RP-LC-MS/MS or 12-step on-line MudPIT. OFFGEL analyses yielded 1398 proteins (identified by 10,269 peptides), while 1428 proteins (11,078 peptides) were detected with the MudPIT approach. Thus, our data shows that both platforms produce highly comparable results in terms of protein/peptide identifications and reproducibility for the sample type analyzed. We achieve more accurate peptide focusing after OFFGEL fractionation with 88% of all peptides binned to a single fraction, as compared to 61% of peptides detected in only one step in MudPIT analyses. Our study suggests that both platforms are equally capable of high quality peptide separation of a sample with medium complexity, rendering them comparably valuable for comprehensive proteomic analyses.Journal of Proteome Research 09/2009; 8(10):4860-9. · 5.11 Impact Factor -
Article: TMP21 transmembrane domain regulates gamma-secretase cleavage.
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ABSTRACT: TMP21 has been shown to be associated with the gamma-secretase complex and can specifically regulate gamma-cleavage without affecting epsilon-mediated proteolysis. To explore the basis of this activity, TMP21 modulation of gamma-secretase activity was investigated independent of epsilon-cleavage using an amyloid-beta precursor proteinepsilon (APPepsilon) construct which lacks the amyloid intracellular domain domain. The APPepsilon construct behaves similarly to the full-length precursor protein with respect to alpha- and beta-cleavages and is able to undergo normal gamma-processing. Co-expression of APPepsilon and TMP21 resulted in the accumulation of membrane-embedded higher molecular weight Abeta-positive fragments, consistent with an inhibition of gamma-secretase cleavage. The APPepsilon system was used to examine the functional domains of TMP21 through the investigation of a series of TMP21-p24a chimera proteins. It was found that chimeras containing the transmembrane domain bound to the gamma-secretase complex and could decrease gamma-secretase proteolytic processing. This was confirmed though investigation of a synthetic peptide corresponding to the TMP21 transmembrane helix. The isolated TMP21 TM peptide but not the homologous p24a domain was able to reduce Abeta production in a dose-dependent fashion. These observations suggest that the TMP21 transmembrane domain promotes its association with the presenilin complex that results in decreased gamma-cleavage activity.Journal of Biological Chemistry 09/2009; 284(42):28634-41. · 4.77 Impact Factor -
Article: Interactions of MAP/microtubule affinity regulating kinases with the adaptor complex AP-2 of clathrin-coated vesicles.
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ABSTRACT: MARK [microtubule-associated proteins (MAPs)/microtubule affinity regulating kinase]/Par-1 (partition defective) phosphorylate MAPs tau, MAP2 and MAP4 at KXGS motifs and thereby regulate microtubule dynamics and transport processes in cells [Drewes et al., Cell1997;89:297-308]. We report here that MARK copurifies with clathrin-coated vesicles (CCVs) via interaction with the adaptor complex AP-2. The adaptin binding site on MARK includes the regulatory loop of its catalytic domain. Immunofluorescence demonstrates the colocalization of MARK with AP-2 and clathrin, as well as other MARK-interacting proteins such as PAK5. The results are consistent with an observed influence of MARK on the trafficking of CCVs. Cell Motil. Cytoskeleton 2009. (c) 2009 Wiley-Liss, Inc.Cell Motility and the Cytoskeleton 07/2009; 66(8):661-72. · 4.19 Impact Factor -
Article: APH1 polar transmembrane residues regulate the assembly and activity of presenilin complexes.
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ABSTRACT: Complexes involved in the gamma/epsilon-secretase-regulated intramembranous proteolysis of substrates such as the amyloid-beta precursor protein are composed primarily of presenilin (PS1 or PS2), nicastrin, anterior pharynx defective-1 (APH1), and PEN2. The presenilin aspartyl residues form the catalytic site, and similar potentially functional polar transmembrane residues in APH1 have been identified. Substitution of charged (E84A, R87A) or polar (Q83A) residues in TM3 had no effect on complex assembly or activity. In contrast, changes to either of two highly conserved histidines (H171A, H197A) located in TM5 and TM6 negatively affected PS1 cleavage and altered binding to other secretase components, resulting in decreased amyloid generating activity. Charge replacement with His-to-Lys substitutions rescued nicastrin maturation and PS1 endoproteolysis leading to assembly of the formation of structurally normal but proteolytically inactive gamma-secretase complexes. Substitution with a negatively charged side chain (His-to-Asp) or altering the structural location of the histidines also disrupted gamma-secretase binding and abolished functionality of APH1. These results suggest that the conserved transmembrane histidine residues contribute to APH1 function and can affect presenilin catalytic activity.Journal of Biological Chemistry 05/2009; 284(24):16298-307. · 4.77 Impact Factor
Top co-authors
Top Journals
Institutions
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2004–2013
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University of Toronto
- • Tanz Centre for Research in Neurodegenerative Diseases
- • Department of Medicine
Toronto, Ontario, Canada
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2011
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The Princess Margaret Hospital
Toronto, Ontario, Canada
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1995
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Ruhr-Universität Bochum
- Institut für Physiologische Chemie
Bochum, North Rhine-Westphalia, Germany
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