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: https://www.ghostery.com/fr/products/

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: http://www.youronlinechoices.com/fr/controler-ses-cookies/, 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

Realytics
Google Analytics
Spoteffects
Optimizely

Targeted advertising cookies

DoubleClick
Mediarithmics

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 cil-dpo@inra.fr or by post at:

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

Dernière mise à jour : Mai 2018

Menu Logo Principal Agrocampus Ouest Angers University

Home Page

Mechanisms of seed stress tolerance acquired during maturation

To discover the mechanisms involved in desiccation tolerance, we focus on comparative analyses between tolerant and sensitive tissues to characterize differences on a molecular level. To identify the actors playing a role in the acquisition of longevity and seedling stress tolerance during maturation, a quantitative approach is used, combining network inference, forward genetics and functional genomics.

We started the molecular characterization of the late maturation phase in the model legume Medicago truncatula. During this three week long phase, between the end of seed filling and seed abscission, longevity increases 30 times. Thus, this model allows us to describe finely mechanisms and regulatory pathways associated with physiological quality. This description is based on the topological analysis of gene regulatory networks build from transcriptomic data to identify regulatory genes that are further characterized for their role in maturation by functional genomics (collaboration J Verdier, Shanghai Plant Stress Centre, CHina). Integration of the phenotyping into the gene regulatory co-expression network led to the identification of modules related to desiccation tolerance and longevity (Verdier et al. , 2013). The topological network analysis has also identified transcription factors that are connected to these two processes.

reseau regulation Verdier

A detailed characterization of the kinetics of accumulation late embryogenesis abundant (LEA) proteins in relation to the acquisition of desiccation tolerance and longevity during seed maturation (Chatelain et. al 2012) showed that a panel of LEA proteins are correlated with longevity. Moreover, a delay of 3 weeks between the accumulation of transcripts and proteins suggests a post-transcriptional regulation of these protective protiens (Verdier et al., 2013).

To study the mechanisms involved in desiccation tolerance, we use a comparative analysis between desiccation tolerant and sensitive tissues. We are performing a comparative analysis of seed development of two legume species: Medicago truncatula (orthodox) and Castanospermum australe (recalcitrant). Comparison of the LEAome demonstrated that certain LEA proteins absent or weakly accumulated in mature seeds of C. australe. The LEA proteome LEA resembles that of Medicago Mtabi3 mutants (Delahaie et al., 2013).

Castano and medicago seeds

Seeds of Medicago truncatula and Castanospermum australe

.

We have sequenced the Castanospermum transcriptome by RNAseq and used these data to produce dedicated arrays to follow the evolution of the transcriptome during the development of the recalcitrant seeds. This study is coupled to ecophysiological and ultrastructural analyses (collaboration Prof. J. Farrant (Univ Cape Town, South Africa) and Henk Hilhorst (Wageningen University). Comparison with development of the orthodox M. truncatula seeds (theme 1) will lead to the identification of the regulatory pathways and their targets that are implicated in the acquisition of desiccation tolerance.

A second physiological model used for a comparative analysis is based on the capacity to re-induce desiccation tolerance in germinated, desiccation-sensitive axes (Buitink et al., 2003). The kinetic analysis of the transcriptome during the re-induction shows a coordinated repression of metabolic genes and an activation of a subset of maturation genes (Buitink et al., 2006), whereas a proteomic analysis identified LEA proteins that are specifically induced in relation to desiccation tolerance. The function of these LEA proteins is being characterized on the molecular level (Boudet et al. 2006 ; Boucher et al., 2010).

See also

Here, other research topics