1. Front Cover.cdr - CORE

A B S T R A C T B O O K – A B S T R A C T S O F P O S T E R S
THE ROLE OF F-BOX-PROTEINS IN STRESS SIGNALING IN ARABIDOPSIS THALIANA
Maria Piisilä, Mehmet Ali Keçeli, Günter Brader, Tapio Palva
Department of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
E-mail: maria.piisila@helsinki.fi
Induced defenses and stress responses play a major role in plant disease resistance and are regulated by a
network of interconnected signal transduction pathways with the plant hormones ethylene (ET), jasmonic
acid (JA) and salicylic acid (SA) as crucial mediators. These specific hormone-mediated signaling cascades
trigger distinct sets of stress-related genes leading to tolerance or resistance. F-box proteins (roughly 700
in Arabidopsis) are important components in these stress responses. They act as members of SCF protein
complexes, which target substrate proteins for modification and degradation and thereby allow plants to
respond rapidly to environmental stress factors. They are involved in various processes including plant
metabolism, hormonal responses as well as responses to environmental stresses. The objective of this
study is to identify and characterize specific F-Box proteins involved in stress signaling and components
interacting with these F-box proteins. To elucidate the function of F-box proteins belonging to subfamily C3
in the regulation of stress responses, we employ a reverse genetic screening approach and characterize T-
DNA mutant lines of this subfamily of F-box proteins for their performance under abiotic (cold, ozone,
drought) and biotic (Erwinia carotovora, Botrytis cinerea, Alternaria brassicicola) stresses. Mutants with
altered stress response phenotypes will be subjected to microarray analysis to elucidate the response
pathways a given F-box protein is involved in. So far, more than 50 F-Box mutant lines were screened with
the pathogens Erwinia carotovora and Botrytis cinerea and cold, ozone, salt and different hormones. We
have found many candidates which are showing clear phenotype to pathogen (Erwinia), ozone, and
hormone (ABA) treatments. Our research is focusing on these confirmed candidates.
Acknowledgements
This work is supported by the Academy of Finland Center of Excellence program.
EMBRYO-SPECIFIC PROTEINS IN CYCLAMEN PERSICUM ANALYZED WITH 2-D DIGE
Ragnhild Lyngved, Jenny Renaut, Jean-Francois Hausman, Tor-Henning Iversen, Anne Kathrine Hvoslef-Eide
Sør-Trøndelag University College, Trondheim, Norway
E-mail: ragnhild.lyngved@hist.no
Somatic embryogenesis can be used to produce artificial seeds of Cyclamen persicum, one of the most
important ornamental plants for the European market, both as a potted plant in northern Europe and a
bedding plant in the cool winters in southern Europe. The aim of this study was to obtain new insights into
the molecular biology of somatic embryogenesis, which in turn can be useful for the improvement of tissue
culture methodology. Total proteins were characterized from two isogenic cell lines of Cyclamen persicum,
one that was embryogenic and one that never has shown any embryogenic capacity. The extracted
proteins were separated by two-dimensional differential gel electrophoresis (2-D DIGE) and selected
proteins were treated using the ETTAN Dalt Spot Handling Workstation. Protein identification was
performed using MALDI-TOF-MS. More than 1200 Cyclamen proteins were detected; 943 proteins were
common to both lines. The different protein patterns of the embryogenic and non-embryogenic cell lines
were obvious: One hundred eight proteins were more abundant in the embryogenic cells, and 97 proteins in
the non-embryogenic cells. Among the differentially expressed proteins, 128 were identified. MALDI-TOF-
MS analysis enabled 27 spots to be proposed as candidates for embryo-specific proteins, as they were
unique to the embryogenic cell line. The proteins identified are involved in a variety of cellular processes,
including cell proliferation, protein processing, signal transduction, stress response, metabolism, and
energy state, but the majority are involved in protein processing and metabolism. The main functions of the
putative embryo-specific proteins have been discussed in proportion to their role in the somatic
embryogenesis process.
STUDYING THE MECHANISMS UNDERLYING SUCROSE-DEPENDENT GENE EXPRESSION
IN A. THALIANA CELL CULTURES
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