Postdoctoral position in INRA, Avignon, France

Proteomics of Tomato Fruit : Diversity and Characterization of proteins involved in quality traits

Project : Fruit quality depends on all the fruit development stages from early cell divisions, which will influence the final fruit size, to later stages when sugars and acids accumulate, and finally on ripening, when aroma and texture set up. In INRA, tomato fruit quality is studied both at genetics, physiology and molecular biology levels in a network of laboratories.

In the Avignon group, molecular markers were used to map QTLs for various quality attributes (Causse et al, 2001, Saliba et al, 2001). Clusters of QTLs were observed, mainly on chromosomes 2, 4 and 9. To further characterize these QTLs, QTL-NILs were derived. Their first evaluation allowed us to separate closely linked QTLs involved in sugar content and fruit weight.

It is now planed to use microarrays to study these NILs, in order to look at the transcriptome modifications. The present project aims at studying the same material at the proteomics level, in a complementary approach.

The 3 objectives of this project are:

1 - Identification by 2D electrophoresis of the protein network variable among near isogenic lines differing for quality traits. Reference gels will be prepared at different stages of fruit development.

2 - Characterisation of the proteins varying during fruit development and among genotypes. The availability of a large tomato EST database (TIGR), together with the new methods for protein identification (Maldi Tof-MS and MS-MS) increased the possibility of protein identification.

3- Evaluation of the intra and interspecific polymorphism revealed by 2D PAGE, estimated on the genotypes we are using as parents of mapping populations for quality traits evaluation. A database of tomato fruit proteins will be set up, based on models available at INRA.

Location : Genetic and Plant Breeding Station INRA Avignon (South of France, 100 kms from the Mediterranean sea and from various mountains). The candidate will join a 30 person molecular genetics laboratory. Our laboratory has equipement for 2D PAGE and software for image analysis. The protein characterization will be performed in the INRA laboratory of M. Rossignol, in Montpellier.

Fellowship is already available, for a non French, but European Ph.D, available for 1 year, renewable once. Salary between 10000 and 14000 French Francs gross per Month (1500-2000 euros) according to the experience of the candidate.

Applicants should send a Curriculum Vitae and addresses of references (preferably by e-mail) to Mathilde Causse (mcausse@avignon.inra.fr)
Station de Génétique et Amelioration des Fruits et Légumes
INRA - BP 94 - 84143 Montfavet - Cedex (France)
Tel : 33 (0) 4 32 72 28 04 Fax : 33 (0) 4 32 72 27 02

Recent references of the laboratory on the subject :

Causse M., Saliba-Colombani V., Buret M., Lesschaeve I., S Issanchou (2001). Genetic analysis of organoleptic quality in fresh market tomato : 2. Mapping QTLs for sensory attributes. Theoretical and Applied Genetics 102 : 273-282.

Faurobert, M. (1997) Application of two-dimensional gel electrophoresis to Prunus armeniaca leaf and bark tissues. Electrophoresis 18;170-173

Saliba-Colombani V., Causse M., Langlois, Philouze J, Buret M. Genetic analysis of organoleptic quality in fresh market tomato (2001) : 1. Mapping QTLs for physical and chemical traits. Theoretical and Applied Genetics 102: 259-272.

Sallandrouze, A., Faurobert, M., Maataoui, M.E, Espagnac, H. (1999) Two-dimensional electrophoretic analysis of proteins associated with somatic embryogenesis development in Cupressus sempervirens L. Electrophoresis 20; 1109-1119

Rossignol M. (2001) Analysis of the plant proteome. Curr Opin Biotechnol. 12(2):131-4.

Santoni V, Rossignol M et al. (1998) Use of a proteome strategy for tagging proteins present at the plasma membrane. Plant J. 16(5):633-41.