Université d'Orléans

Cellular Signaling

team photo

Professor assistants (lecturers):   Dr Sabine Carpin (supervisor)
Dr Christiane Depierreux, Dr François Héricourt, Dr Frédéric Lamblin

Engineer and technician :
Dr Françoise Chefdor, Mélanie Larcher

 

Context

Earth's climate has changed throughout history and a global climate change is observed due to human activities. The last IPCC report confirms that extreme events and disasters as drought will become more intensive. In our regions, more intensive and frequent droughts will lead to reduced water availability to food crop, forest and populiculture.

Poplar culture which is economically important in the « Région Centre - Val de Loire », is typically restricted to well irrigated zones and will be consequently strongly affected by more drastic drought events. In the future, one major issue for poplar culture in this context will be to understand signaling pathways which contribute to perceive the stress leading to poplar adaptation to drought.

Such signaling pathways have been identified and one of them corresponds to a multi-step phosphorelay system (MSP). This kind of signaling pathway is composed by three partners : a receptor belonging to the Histidine-aspartate Kinase familly (HK), a shuttle protein belonging to the Histidine-containing Phosphotransfer protein family (HPt), and a third partner belonging to the Response Regulator protein family (RR) which comprises transcription factors (RR-B).

In poplar, we identified two HK proteins (HK1a and b) which could play a role in drought perception (Chefdor et al., 2006 ; Héricourt et al., 2016), 10 HPt proteins (HPt1 to 10) (Héricourt et al., 2013), 9 RR-B (Bertheau et al., 2012 ; 2013 ; 2015) and 10 RR-A (Chefdor et al., 2018).

A preferential partnership was identified between some of these proteins as shown in the Figure below.

MSP 

Scheme of MSP potentialy involved in perception of drought in poplar

 

MSP

MSP partners and their relationship

Project

Cytokinins have been shown as negative regulators during drought (Tran et al., 2007) and it is now accepted that these phytohormones can play a role in plant acclimation/adaptation/tolerance during drought via MSP pathway (Li et al., 2016). Indeed, the key to understand abiotic stress tolerance resides in understanding the plant’s capacity to accelerate/maintain or repress growth (Dolferus 2014).

Consequently, plants constantly oscillate between normal or stress conditions thus between growth (acceleration or maintain) and stress tolerance (growth repression) via a shared MSP pathway between these two signals, cytokinin and drought.

However, understanding how both signals, drought and cytokinins, perceived by distinct receptors, can result in specific responses through an identical pool of HPt and RR-B proteins, remains to be determined.

 

Our project focus on the study of MSP signaling pathways, trying to understand how those signaling pathway could permit plants to conserve specific responses to both signals and continue to grow during drought.

 

Our aims :

- To study HK1a and b roles and their operating mechanism

- To confirm the specificity between HPt2, 7 and 9 with HK1 compared to cytokinin receptors (HK2, 3 and 4).

- To study the roles of RR-B partners of HPt2, 7 and 9.

- To study RR-A roles in drought signaling.

 

Techniques

In vitro culture, hydroponic culture, protoplasts transformation, poplar agrotransformation, yeast two-hybrid, classical molecular biology techniques (RNA and DNA extraction, cloning techniques, sequencing, PCR, RT-PCR, western blot, etc …)

 in vitro culture

Poplar transformation


Two-hybrid test RR18/HPt

Collaborations

- Laboratory BBV, Université de Tours, France

- Centre de Biophysique Moléculaire (CBM), CNRS, Orléans, France

- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Japan

- Dipartimento di Bioscienze e Territorio, Università degli Studi del Molise, Italy


Publications

2018

Chefdor F., Héricourt F., Koudounas K., Carqueijeiro I., Courdavault V., Mascagni F., Bertheau L., Larcher M., Depierreux C., Lamblin F., Racchi M.L., and Carpin S. Highlighting type A RRs as potential regulators of the dkHK1 multistep phosphorelay pathway in PopulusPlant Science 277: 68-78.

2016

Héricourt F., Chefdor F., Djeghdir I., Larcher M., Lafontaine F., Courdavault V., Auguin D., Coste F., Depierreux C., Tanigawa M., Maeda T., Glévarec G. and Carpin S. Functional Divergence of Poplar Histidine-Aspartate Kinase HK1 Paralogs in Response to Osmotic Stress. International Journal of Molecular Sciences 17: 2061-2079.

2015

Bertheau L., Djeghdir I., Fourreau E., Chefdor F., Glévarec G., Oudin A., Depierreux C., Morabito D., Brignolas F., Courdavault V., Héricourt F., Auguin D., Carpin S. Insights into the involvement of B-type RRs in the osmosensing signaling pathway in Populus. Plant Physiology and Biochemistry 94: 244-252.

2013

Bertheau L, Miranda M, Foureau E, Rojas HoyosL. F., Chefdor F, Héricourt F, Depierreux C, Morabito D, Papon N, Clastre M, Scippa G. S., Brignolas F, Courdavault V, Carpin S In planta validation of HK1 homodimerization and recruitment of preferential HPt downstream partners involved in poplar multistep phosphorelay systems. Plant Biosystems 147: 991-995.

Héricourt F.*, Chefdor F.*, Bertheau L., Tanigawa M., Maeda T., Guirimand G., Courdavault V., Larcher M., Depierreux C., Bénédetti H., Morabito D., Brignolas F., Carpin S. Characterization of histidine-aspartate kinase HK1 and identification of Histidine Phosphotransfer proteins as potential partners in a Populus multistep phosphorelay. Physiologia Plantarum 149: 188-199 (* first co-authors).

2012

Bertheau L., Chefdor F., Guirimand G., Courdavault V., Depierreux C., Morabito D., Brignolas F., Héricourt F., Carpin S. Identification of five B-type response regulators 1 as members of a multistep phosphorelay system interacting with Histidine-containing Phosphotransfer partners of Populus osmosensor, BMC Plant Biology 12: 241-254.

2006

Chefdor F., Bénédetti H., Depierreux C., Delmotte F., Morabito D., Carpin S. Osmotic stress sensing in Populus: Components identification of a phosphorelay system. FEBS Letters 580: 77-81.


Communications

May 2019

Conference of Dr Sabine Carpin

Erasmus Program, University of Florence (Italy)

"Multistep phosphorelay system, a signaling pathway between growth and drought tolerance"

DAGRI, University of Florence (Italy)

Affiche conference

Conference of Dr Roberto de Philippis

DAGRI, University of Florence (Italy)

"Exploitation of microbial photosynthesis for environmentally sustainable biotechnological processes"

LBLGC, University of Orléans (France)


April 2019

Affiche Symposium

Conference of Dr Sabine Carpin

EMBO Symposium

"Stress sensing in tree species"

Grand Hotel, New Delhi (India)

Conference of Dr Sabine Carpin

Workshop ICGEB

Affiche Workshop

"During drought, how to choose between growth and tolerance?"

ICGEB, New Delhi (India)

Conference of Dr François Héricourt

Workshop ICGEB

"Perception of drought in poplar: search for osmosensor and its ligand"

ICGEB, New Delhi (India)


November 2018

first page

Seminar of Dr Françoise Chefdor

Cellular Signaling team, LBLGC

"Highlighting type A RRs as potential regulators of the dkHK1 multistep phosphorelay pathway in Populus"

LBLGC, University of Orléans


September 2018

Conference photo

Conference of Pr Ashwani Pareek

Jawarharlal Nerhu University, New Delhi (India)

"Towars improving abiotic stress tolerance in rice"

Hôtel Dupanloup, Studium Orléans


Students formation by research 

PhD

- Inès Djeghdir (defended in 2016)

- Lucie Bertheau (defended in 2013)

- Françoise Chefdor (defended in 2006)

Master degree

- Master « Agrosciences, environnement, territoires, paysage, forêt », Orléans

- Master Biologie Moléculaire et Cellulaire « BMC », Orléans

- Master Biologie des Plantes et des Micro-organismes, Biotechnologies, Bioprocédés, Montpellier

  Spécialité Biologie des plantes

- Master Biologie, Agronomie, Santé, Rennes

  Spécialité Sciences cellulaire et moléculaire du vivant

Bachelor degree

- Licence 3 parcours BOPE and BMC, Orléans

- BTS Biotechnologie, Lycée Jacques Monod, St Jean de Braye

 

Grants

Conseil régional du Centre : projet d’initiative académique 2013, SiSCyLi

Conseil régional du Centre : projet « recherche » Appel Blanc 2008, SiSeP

Conseil Général du Loiret : projet de recherche innovant 2008