Patrice ESLIN

Doctor in Life Sciences and Earth, Maître de Conférences, Classe Normale
Speciality: Entomology, Insect physiology, Host-parasite interaction
Team: BIPE
patrice.eslin@u-picardie.fr

 

 

Research interests

My research has two main objectives:

Key words

Parasitoid, Drosophila, ecophysiology, host-parasite relationships, cellular immunity in insects.

Recent or current projects

Search and comparison of immune evasion factors in parasitoids of the Asobara genus
We have demonstrated, within the Asobara genus (Braconid), the existence of an unexpected variety of avoidance mechanisms of the immune defense to which parasitoids are exposed in their Drosophila hosts. Indeed, in this genus of parasitoids, some species have adopted a ‘passive’ strategy whereas others opted for a frankly, even « aggressive « , active mechanism through which the parasite acts directly on the cellular defense system of its host. Because of this heterogeneity of encapsulation avoidance, parasitoids of the Asobara genus represent a particularly interesting model for studying immune interactions in host-parasitoid systems. In addition, the study of molecular factors responsible for virulence in A. japonica has allowed us to show an effect of the venom endows associated with an antidote effect of ovarian fluids.
The continuation of this work is to complete the identification of molecular factors responsible for virulence in A. japonica and compare the origin of these factors with those of factors already described in other species of parasitoids. Virulence strategies of the endoparasitic Asobara species can be compared with those developed by other species which, although phylogenetically close, have adopted an ectoparasitic mode of development.

Study of the potential of cellular immunity in Drosophila
We explored the potential of cellular immunity in Drosophila larvae belonging to the obscura group. The results show that the natural immune deficiency we had previously described in Drosophila subobscura can be generalized to most species of the obscura group, without being a characteristic of this group. Indeed, besides this species that seem utterly incapable of producing lamellocytes, others can produce atypical hemocytes that allow them to defend against parasitoids. These observations raise many questions, both physiological, ecological and evolutionary.
On the other hand, an asian invasive species of fruit fly, D. suzukii, has been recorded for the first time in North America and Europe (Spain) in 2008. Within two years, this species has spread throughout the French territory, Switzerland, Slovenia and Germany and is already proving to be a serious pest, especially for the production of cherries, strawberries and raspberries. The objective of the work initiated is to characterize the level of resistance of this new host towards european parasitoids and to identify the cellular factors involved.

Measurement of temperature effects on Drosophila host resistance
In my previous work, we showed that hemocyte population is a key factor in Drosophila host resistance to parasitoids. In 2008, the ANR supported our project on the influence of climate change on the evolution of host-parasitoid interactions (CLIMEVOL project). One of the strengths of this project is to evaluate the effects of temperature on Drosophila hosts resistance. Besides my involvement in various aspects of the project, I am in charge of assessing the effects of temperature on the hemocyte population and level of host resistance in Drosophila.

Research of reservoir plants for the invasive species Drosophila suzukii
The D. suzukii species mentioned in project 3 proves to be a serious pest for red fruits. Its varied diet led us to wonder about the diversity of wild host plants that could be used during the phases of invasion by this insect. Laboratory studies coupled with trapping campaigns on the ground were initiated in autumn 2011. The first results appear very promising.

Teaching

Parasitology, Cellular and Molecular Biology, Integrated Crop Protection, Comparative Anatomy, Histology, Entomology applied to crop production, Cellular immunity in insects.

Supervision or co-supervision of PhD thesis

Sebastien Havard. Co-direction of his thesis entitled  » Defense potential and cell encapsulation in Drosophila of the obscura group », defended in October 2009.
Alix nno Mabiala. Co-direction of her thesis entitled « Mechanisms and agents of virulence in Braconid parasitoid wasps of the Asobara genus « , defended in October 2009.
Mathilde Poyet. Co-direction of her Thesis « Responses of communities of Drosophila and their parasitoids against the invasion by the pest Drosophila suzukii: physiological, populational and ecological studies  » defended in 2014.

Administrative tasks

Member of Recruitment Committee 67-68th sections of UPJV since October 2008.
Advisory Member of  the Documentation Center in University of Picardie – Jules Verne since Sept. 2000.
Member of the « Documentation » Working Group of the Science Faculty of Amiens.
Head of Finance for the Service of Animal Biology, University of Picardie – Jules Verne since Sept. 2002.

Recent publications

Mennerat A. et Eslin P. (2014) A quoi servent les parasites ? Faune sauvage, santé et biodiversité, QUAE, édité par Serge Morand, François Moutou, Céline Richomme et Michel Gauthier-Clerc, pp. 51-58.
Poyet M., Eslin P., Héraude M., Le Roux V., Prévost G., Gibert P. and Chabrerie O. (2014) Invasive host for invasive pest : When the invasive Asiatic cherry fly (D. suzukii) meets the invasive American black cherry (P. serotina) in Europe. Agricultural and Forest Entomology. 16(3): 251-259.
Poyet M., Havard S., Prévost G., Chabrerie O., Doury G., Gibert P. and Eslin P., (2013) Resistance of Drosophila suzukii to the larval parasitoids Leptopilina heterotoma and Asobara japonica is related to haemocyte load. Physiological Entomology, 38 : 45-53.
Prévost G., Eslin P., Cherqui A., Moreau S. and Doury G. (2012) When parasitoids lack polydnaviruses, can venoms subdue the host ? The study case of Asobara species. In «Parasitoid Viruses : Symbionts and Pathogens » (Drezen J.M., Beackage N., Ed., 1st Edition), Elsevier. pp. 255-266.
Chabert S., Allemand R., Poyet M., Eslin P. and Gibert P. (2012) Ability of European parasitoids (Hymenoptera) to control a new invasive Asiatic Drosophila pest, D. suzukii, Biological Control, 63 : 40-47.
Havard S., Doury G., Ravallec M., Brehélin M., Prévost G. and Eslin P. (2012)  Structural and functional characterization of pseudopodocyte, a shaggy immune cell produced by two Drosophila species of the obscura group. Developmental and  Comparative Immunology, 36(2) : 323-31.