Myosin VI contains an inserted sequence that is unique among myosin superfamily members and has been suggested to be a determinant of the reverse directionality unusual motility motor. It thought each head two-headed molecule binds one calmodulin (CaM) by means single “IQ motif”. Using truncations protein electrospray ionization(ESI)-MS, we demonstrate in fact two CaMs. One CaM conventional IQ motif either with or without calcium likely plays regulatory role when its N-terminal lobe. The...

BackgroundThe Wave complex activates the Arp2/3 complex, inducing actin polymerization in lamellipodia and membrane ruffles. The is composed of five subunits, smallest which, Brick1/Hspc300 (Brk1), least characterized. We previously reported that, unlike other Brk1 also exists as a free form.Principal FindingsHere we report that this form homotrimers. Using novel assay which purified electroporated into HeLa cells, were able to follow its biochemical fate cells show becomes incorporated...

ABSTRACT Microtubules, components of the cell cytoskeleton, play a central role in cellular trafficking. Here we show that rotavirus infection leads to remodeling microtubule network together with formation tubulin granules. While most microtubules surrounding nucleus depolymerize, others appear packed at periphery. In depolymerization areas, granules are observed; they colocalize viroplasms, viral compartments formed by interactions between proteins NSP2 and NSP5. With purified proteins,...

The organization of spacer DNA connecting 160 base-pair cores bovine thymus polynucleosomes has been studied by a combination biochemical and electron microscopic techniques. results reveal that major fraction chromatin consists spectrum repeating units; these differ from each other up to 20 base-pairs due variation in length. Those which have larger lengths are processed micrococcal nuclease mononucleosomes more rapidly than those organized with shorter spacers. Although distribution...

Mammalian prions, the pathogens that cause transmissible spongiform encephalopathies, propagate by self-perpetuating structural information stored in abnormally folded, aggregated conformer (PrPSc) of host-encoded prion protein (PrPC). To date, no model related to assembly organization satisfactorily describes how strain-specified is encoded and which mechanism this transferred PrPC. achieve progress on issue, we correlated PrPSc quaternary transition from three distinct strains during...

During rotavirus infection, replication and packaging of the viral genome occur in factories, termed viroplasms. The nonstructural protein NSP5 is a major building block viroplasms; it recruits polymerase VP1, core VP2, ATPase NSP2 inside viroplasm to form complex. Here we report that unique metalloprotein coordinates [2Fe-2S] iron-sulfur cluster as demonstrated by metal labile sulfide contents, UV-visible light absorption, electron paramagnetic resonance. Point mutations allowed us identify...

Respiratory syncytial virus (RSV) RNA synthesis takes place in cytoplasmic viral factories also called inclusion bodies (IBs), which are membrane-less organelles concentrating the polymerase complex. The assembly of IBs is driven by liquid-liquid phase separation promoted interactions between nucleoprotein N and phosphoprotein P. We recently demonstrated that cyclopamine (CPM) inhibits RSV multiplication disorganizing hardening IBs. Although a single mutation transcription factor M2-1...

Prion diseases are characterized by conformational changes of a cellular prion protein (PrP(C)) into β-sheet-enriched and aggregated conformer (PrP(Sc)). Shadoo (Sho), member the family, is expressed in central nervous system (CNS) highly conserved among vertebrates. On basis histoanatomical colocalization sequence similarities, it suspected that Sho PrP may be functionally related. The downregulation expression during pathology direct interaction between PrP, as revealed two-hybrid...

Abstract Prions are neurotropic pathogens composed of misfolded assemblies the host-encoded prion protein PrPC which replicate by recruitment and conversion further an autocatalytic seeding polymerization process. While it has long been shown that mouse-adapted prions cannot rapidly cleared in transgenic PrP0/0 mice invalidated for PrPC, these experiments have not done with other prions, including from natural resources, more sensitive methods to detect biological activity. Using expressing...

Atypical/Nor98 scrapie (AS) is an idiopathic infectious prion disease affecting sheep and goats. Recent findings suggest that zoonotic prions from classical bovine spongiform encephalopathy (C-BSE) may copropagate with atypical/Nor98 in AS brains. Investigating the risk poses to humans crucial.

The prion protein (PrP) misfolds and assembles into a wide spectrum of self-propagating quaternary structures, designated PrPSc. These various PrP superstructures can be functionally different, conferring clinically distinctive symptomatology, neuropathology infectious character to the associated diseases. However, satisfying molecular basis structural diversity is lacking in literature. To provide mechanistic insights etiology polymorphism, we have engineered set 6 variants human obtained...

Abstract In peripherally acquired prion diseases, prions move through several tissues of the infected host, notably in lymphoid tissue, long before occurrence neuroinvasion. Accumulation can even be restricted to tissue without neuroinvasion and clinical disease. Several experimental observations indicated that presence differentiated follicular dendritic cells (FDCs) structures strain type are critical determinants extraneural replication. this context, report granulomatous apparently...

In mammals, Prion pathology refers to a class of infectious neuropathologies whose mechanism is based on the self-perpetuation structural information stored in pathological conformer. The characterisation PrP folding landscape has revealed existence plethora pathways conducing formation structurally different assemblies with biological properties. However, biochemical interconnection between these diverse remains unclear. oligomerisation process leads neurotoxic and soluble called O1...

The protein DSP1 belongs to the group of HMG-box proteins, which share common structural feature HMG-box. This approximately 80 amino acid long motif binds DNA via minor groove. was discovered as a transcriptional co-repressor Dorsal in Drosophila melanogaster and then shown participate remodeling chromatin. By means sequence alignment gene organization, classified fly homologue vertebrate proteins HMGB1/2. contains two HMG boxes flanked by glutamine-rich domains at N-terminus. In addition,...

Summary Prion diseases, or Transmissible Spongiform Encephalopathies (TSE), are neurodegenerative disorders caused by the accumulation of misfolded conformers (PrP Sc ) cellular prion protein C ). During pathogenesis, PrP seeds disseminate in central nervous system and convert leading to formation insoluble assemblies. As for conventional infectious variations clinical manifestation define a specific strain which correspond different structures. In this work, we implemented recent...

Summary Prion diseases are fatal neurodegenerative that affect mammals through the transconformation of a host protein, prion protein (PrP), into toxic and pathogenic conformer termed PrP Sc . Until now, diagnosis is only confirmed with post-mortem histology study central nervous system. Among methods to detect etiological agent, in vitro amplification techniques have emerged as very sensitive, highly specific rapid tools, even though some strains remain refractory or difficult amplify. Here...

Mammalian prions are neurotropic pathogens formed from PrP Sc assemblies, a misfolded variant of the host‐encoded prion protein C . Multiple conformations or strains self‐propagate in host populations mouse models diseases, exhibiting distinct biological and biochemical phenotypes. Constrained interactions between confer species specificity regulate cross‐species transmission. The pathogenicity fibrillar assemblies derived bacterially expressed recombinant (rPrP) has been instrumental...

Prion diseases, or transmissible spongiform encephalopathies (TSEs), are neurodegenerative disorders caused by the accumulation of misfolded conformers (PrP

Genetically encoded ratiometric fluorescent probes are cutting-edge tools in biology. They allow precise and dynamic measurement of various physiological parameters within cell compartments. Because data extraction analysis time consuming may lead to inconsistencies between results, we describe here a standardized pipeline for•Semi-automated treatment time-lapse fluorescence microscopy images.•Quantification individual signal.•Statistical the data.First, dedicated macro was developed using...

Respiratory syncytial virus (RSV) RNA synthesis takes place in cytoplasmic viral factories also called inclusion bodies (IBs), which are membrane-less organelles concentrating the polymerase complex. IBs assembly is driven by liquid-liquid phase separation promoted interactions between nucleoprotein N and phosphoprotein P. We recently demonstrated that cyclopamine (CPM) inhibits RSV multiplication disorganizing hardening IBs. Although a single mutation transcription factor M2-1 induced...