Know more

Our use of cookies

Cookies are a set of data stored on a user’s device when the user browses a web site. The data is in a file containing an ID number, the name of the server which deposited it and, in some cases, an expiry date. We use cookies to record information about your visit, language of preference, and other parameters on the site in order to optimise your next visit and make the site even more useful to you.

To improve your experience, we use cookies to store certain browsing information and provide secure navigation, and to collect statistics with a view to improve the site’s features. For a complete list of the cookies we use, download “Ghostery”, a free plug-in for browsers which can detect, and, in some cases, block cookies.

Ghostery is available here for free:

You can also visit the CNIL web site for instructions on how to configure your browser to manage cookie storage on your device.

In the case of third-party advertising cookies, you can also visit the following site:, offered by digital advertising professionals within the European Digital Advertising Alliance (EDAA). From the site, you can deny or accept the cookies used by advertising professionals who are members.

It is also possible to block certain third-party cookies directly via publishers:

Cookie type

Means of blocking

Analytical and performance cookies

Google Analytics

Targeted advertising cookies


The following types of cookies may be used on our websites:

Mandatory cookies

Functional cookies

Social media and advertising cookies

These cookies are needed to ensure the proper functioning of the site and cannot be disabled. They help ensure a secure connection and the basic availability of our website.

These cookies allow us to analyse site use in order to measure and optimise performance. They allow us to store your sign-in information and display the different components of our website in a more coherent way.

These cookies are used by advertising agencies such as Google and by social media sites such as LinkedIn and Facebook. Among other things, they allow pages to be shared on social media, the posting of comments, and the publication (on our site or elsewhere) of ads that reflect your centres of interest.

Our EZPublish content management system (CMS) uses CAS and PHP session cookies and the New Relic cookie for monitoring purposes (IP, response times).

These cookies are deleted at the end of the browsing session (when you log off or close your browser window)

Our EZPublish content management system (CMS) uses the XiTi cookie to measure traffic. Our service provider is AT Internet. This company stores data (IPs, date and time of access, length of the visit and pages viewed) for six months.

Our EZPublish content management system (CMS) does not use this type of cookie.

For more information about the cookies we use, contact INRA’s Data Protection Officer by email at or by post at:

24, chemin de Borde Rouge –Auzeville – CS52627
31326 Castanet Tolosan CEDEX - France

Dernière mise à jour : Mai 2018

Menu Logo Principal

Home page

A physicochemical approach to the structure of the PrPC prion protein : Conformational plasticity of peptides of the 121-170 (H1-S2) region of the ovine prion protein

Inra Prod. Anim., 2004, Numéro hors série, 39-44


1 Département Régulations Développement et Diversité Moléculaire, Muséum National d’Histoire Naturelle, UMR 5154 CNRS-MNHN, Chimie et Biochimie des Substances Naturelles, UMR 5154 CNRS-MNHN, 63 rue Buffon, F-75005 Paris

2 Laboratoire d’Etude des Interactions des Molécules Alimentaires, INRA, rue de la Géraudière, F-44026 Nantes
3 Département Régulations Développement et Diversité Moléculaire, Muséum National d’Histoire Naturelle, UMR 5153 CNRSMNHN Régulation et dynamique des génomes, 43 rue Cuvier, F-75005 Paris


The conversion of the prion protein from the normalnon-pathogenic cellular form (PrPC), to the pathogenicmisfolded isoform (PrPSc) involves an increase of theamount of beta sheet in the protein structure, whichfavours aggregation, formation of fibrils and resistanceto proteinase K. The three-dimensional structure ofPrPc, which has been determined for four species, isextremely conserved. It contains a flexible segment atthe N-terminus and a globular part composed of twobeta-strands (S1, S2) and three alpha-helices (H1 to H3) associated by loops (L1 to L5). The protein fragmentcorresponding to helix H1 is an autonomousregion that can adopt a helical structure by itself. Bycontrast, the peptide that contains region H1-L3-S2(PrPH1-L3-S2) adopts different conformations, as alsoshown for the protein. These results allow proposinghelix H1 as one of the structural motifs of the prionprotein able to initiate the transconformation, i.e. theconversion of the benign prion protein into its pathogenicisoform. The key role played by helix H1 in thetransconformation was analysed in a physicochemicalstudy using a series of peptides of different sequencesand lengths (9 to 33 residues, sheep sequence) designedin the [133-165] region that contains the structuralmotifs L2-H1-L3-S2. The main results, which aredescribed here, show the great stability of helix H1,particularly in the presence of either loop L2 or loopsL2 and L3. The absence of loop L2 associated to thepresence of beta-strand S2 decreases the stability ofhelix H1. It is possible that loop L2 could play a specialrole, as suggested by the fact that this loop can interactwith PrPC. Such an interaction could contribute tothe mechanisms that are involved in the interactionbenign prion protein / pathogenic prion protein, whichis implicated in the propagation of the disease. Theseresults, which should be confirmed and developped,lead to propose loop L2 and strand S2 as two regionsthat could assume a "regulation" of the stability ofhelix H1, which appears as a key region in the pathogenicconversion process.

Download documents