Proteomic Analyses of Somatic and Zygotic Embryos and Endosperm Tissue of Cyclamen persicum

authored by: T. Winkelmann, D. Heintz, A. Van Dorsselaer, M. Serek, H. P. Braun
Abstract: In the horticulturally important ornamental species Cyclamen persicum somatic embryogenesis is an efficient vegetative propagation method and interest is given in the development of artificial seeds. Previous studies have shown that cyclamen somatic embryos can successfully be encapsulated and desiccated, but need external supply of nutrients for germination. Objectives of the present study were to systematically compare the proteomes of zygotic embryos, somatic embryos grown in liquid medium containing 30 or 60 g L^-1 sucrose, germinating embryos of both types and endosperm in order to obtain novel insights into seed and germination physiology. Using high resolution two-dimensional isoelectric focusing/sodium dodecylsulfate polyacrylamide gel electrophoresis (2D IEF/SDS PAGE), 74% of the proteins expressed in zygotic embryos were found in similar abundance in somatic embryos grown in 60 g L ^-1 sucrose. Among the differentially accumulating proteins, four enzymes of the primary metabolism involved in glycolysis (UDP-glucose pyrophosphorylase, fructose bisphosphate aldolase, triosephosphate isomerase, glyceraldehyde-3-phosphate dehydrogenase) were specifically induced in somatic embryos. Proteins of high abundance in embryos and endosperm and comparatively low abundance in germinating embryos represent candidates for seed storage proteins, which so far were unknown for C. persicum. 11S globulin proteins identified by mass spectrometry were present at high levels in somatic embryos, zygotic embryos and endosperm, whereas 7S globulins were detected in endosperm and zygotic embryos mainly. Xyloglucans are known to be another group of seed storage compounds in C. persicum. Their formation was not studied so far. Interestingly, xyloglucan endotransglycosylases, an enzyme group involved in xyloglucan biosynthesis but also its degradation were found to be highly expressed in endosperm tissue.
Organisation(s): Research section Reproduction and Development
Institute of Plant Genetics
External Organisation(s): University of Strasbourg
Type: Conference contribution
Pages: 163-169
No. of pages: 7
Publication date: 09.2006
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Horticulture
Electronic version(s): https://doi.org/10.17660/ActaHortic.2006.714.18 (Access: Unknown)