Increase gelling agent concentration promotes somatic embryo maturation of hybrid larch (Larix x eurolepis): a 2-DE proteomic analysis
Résumé
Somatic embryogenesis represents an important clonal propagation method for conifers (Lelu-Walter and Pâques 2009). Desiccation treatments applied to hybrid larch somatic embryos promote plantlet development (Lelu et al. 1995). Water availability could also be modulated via the gelling agents of the culture medium. We investigated the effect of high gellan gum concentration in the medium during somatic embryo maturation of hydrid larch. High gellan gum concentration of 8 gL-1 was compared to the normal concentration of 4 gL-1 at different stages of maturation. The decrease of water availability at 8 weeks on 8 gL-1 impacted osmotic potential, water content and dry weight in the embryos. The proteomic study at 1 and 8 weeks on both culture media, indicated that 62 differing proteins at 1 week corresponded to “Carbohydrate metabolism”, “Genetic information processing” or "Environmental information processing”. The physiological parameters as well as the identified proteins suggested a stress status of the embryos when they were cultivated on 4 gL-1.
We report results that describe for the first time 2-DE proteomic analysis somatic embryo maturation in larch. The protein expression profiles will provide novel insights into the process of hybrid larch somatic embryo maturation, and an outline for practical application.