Book of Abstracts - Geyseco

03 - S - Selected Abstracts for Oral Presentations
sperm cells, suggesting active epigenetic reprogramming as well
as posttranscriptional regulation of gene expression. Our deep sequencing
analysis of small RNA libraries from pollen and sperm
cells revealed that 49 known miRNA families are enriched in the
male gametes. We could predict 31 potentially novel miRNAs
in sperm cells and can show cleavage of some of their predicted
target transcripts in pollen samples. Thus our comparative
sRNA sequencing coupled with the transcriptome data and pollen
5’RACE analysis suggest that miRNA pathways are active during
sperm cell specification. Moreover, we are testing the hypothesis
that some miRNAs accumulate in the male gametes to be
delivered to the female gametes upon fertilization and only play
a role during early embryonic development.
S05-001: MOLECULAR APPROACHES TO IMPROVING
SORGHUM QUALITY: A CEREAL CROP FOR FOOD,
FEED AND BIOMATERIALS
Godwin, I. D.¹* - Gilding, E.¹ - Prentis, P.¹ - Frere, C.¹ - Mudge,
A.¹ - Liu, G.¹ - Lambrides, C.¹ - William, S. B.¹ - Campbell, B.C.¹
- Mace, E.S.² - Cruickshank, A.² - Jordan, D.R.²
¹The University of Queensland
²AgriScience Queensland
*Corresponding author e-mail: i.godwin@uq.edu.au
The sorghum genome sequence will facilitate the development
of more highly saturated genome maps with database mining for
Single Nucleotide Polymorphisms (SNP). This will also enable
rapid in silico identification of candidate genes in mapped regions
known to be involved in the expression of Quantitative
Trait Loci (QTL) and allelic diversity for important grain quality,
cell wall quality, abiotic stress tolerance and developmental genes.
Internationally, great interest in the sorghum genome derives
from its importance as a grain and forage crop, as a model for
the maize and sugarcane genomes, and most recently because
of its emerging potential as a biomass crop. The combination of
new tools such as whole genome mapping and selection, developments
in association mapping, robotics and computational
biology for high throughput sequencing and sorghum transgenics
make for a powerful package for sorghum genetic improvement.
We have produced sorghums with altered protein:starch matrix
by targeting the S-S cross-linking of the beta- and gammakafirins.
We have characterised a range of cultivated and wild
sorghum germplasm for grain quality parameters, and are in the
process of manipulating genes involved in seed storage protein
and starch biosynthesis to alter the nutritional and bio-industrial
quality of the endosperm. Additionally, forward and reverse genetics
approaches are underway to improve stover quality for
nutritional and bio-industrial applications.
S05-002: NOVEL INSIGHTS INTO THE PHYSIOLOGI-
CAL FUNCTION OF LATEX IN TARAXACUM SPP
Wahler, D.¹* - Colby, T.² - Schulze Gronover, C.³ - Prüfer, D.¹
¹University of Münster - Institut für Biochemie und Biotechnologie
der Pflanzen (WWU-IBBP)
²MPIZ Cologne
³Fraunhofer Institute for Molecular Biology and Applied Ecology
(IME), Germany
*Corresponding author e-mail: daniela.wahler@uni-muenster.de
Ten percent of all angiosperms contain specialized cells with a
remarkable milky cytoplasm called latex. The genera Taraxacum
is probably most familiar among latexcontaining plants. So far,
no physiological function of latex could be determined but a
participation in plant defense is discussed. Additionally, some
latex-containing plants such as T. koksaghyz synthesize natural
rubber and the question rose whether this biopolymer also contributes
to defense responses. Here, we present a proteomic approach
on Taraxacum spp. to get a better insight into the biology of
latex and particularly into rubber biosynthesis. Through establishment
of reliable methods for protein purification, visualization
on two-dimensional gels and subsequent crossspecies identification
39% of all visible spots were identified. A high proportion
could be related to plant defense giving yet another hint that a
prime role of latex is defense. By comparative analyses of the latex
proteomes of the closely related rubber producer T.koksaghyz
and non-rubber producer T. officinale, differentially expressed
proteins were detected that are thus likely to be factors of rubber
biosynthesis. Among them three members of the rubber elongation
factor superfamily that are known to be essential factors in
rubber biosynthesis exhibited a deviating expression pattern in
the two Taraxacum species.
S05-003: IMPROVEMENT OF PLANT DEFENSES
THROUGH METABOLIC ENGINEERING OF LIMONE-
NE IN TRANSGENIC ORANGE FRUITS
Rodriguez, A.¹* - San Andres, V.¹ - Redondo, A.¹ - Alquezar, B.¹ -
Cervera, M.¹ - Shimada, T.² - Gadea, J.³ . Rodrigo, M.J.4 - Zacarias,
L.4 - Castañera, P.5 - Palou, L.¹ - Lopez, M.M.¹ - Peña, L.¹
¹IVIA - Instituto Valenciano de Investigaciones agrarias
²National Institute of Fruit Tree Science (NIFTS)
³Instituto de Biología Molecular y Celular de Plantas (IBMCP)
4
Instituto Agroquímica y Tecnología de Alimentos (IATA – CSIC)
5
Centro de Investigaciones Biológicas (CIB – CSIC)
*Corresponding author e-mail: rodriguez_anabai@gva.es
Plants produce a wide diversity of secondary metabolites, many
of which are volatile compounds. Terpenes are major components
of fruits, which suggests that serve for seed protection
against pests and pathogens and as attractants of frugivorous
animals. However, proof that a specific fruit terpene attracts or repels
a specific animal remains to be obtained. The extraordinarily
high amount of limonene that accumulates in orange oil glands
suggests an important biological role for this terpene compound
in interactions with the environment. To test this, we manipulated
oil gland chemistry by antisense downregulation of limonene
expression in orange fruits. Transgenic plants had reduced limonene
accumulation in fruit peel. A gene expression analysis was
performed with a 20K citrus microarray and results indicated that
monoterpene downregulation was activating the immune response
in fruit peel. To test whether antisense suppression resulted
in an improvement in the response of the fruit against pest and
pathogens, antisense (AS) and control (EV) fruits were challenged
with the Medfly Ceratitis capitata, the fungus Penicillium
digitatum, and the bacterium Xanthomonas axonopodis. Medfly
males were more attracted to EV fruits, indicating that limonene
emission was attracting insects to the fruit. Moreover, AS fruits
showed a marked resistance against both pathogens characterised
for their inability to establish infection in peel tissues.
These results provide a more comprehensive view of the role
of terpene volatiles as attractors of insects and microorganisms,
which break the external peel layer, thus promoting pulp and seed
feeding by frugivores. The strategy represents a very promising
alternative for increasing resistance to pests and pathogens in
plants.
S05-004: PENETRATION AND TRANSPORT OF NA-
NOPARTICLES IN LIVING PLANTS AS A TOOL FOR
DIRECTED DELIVERY OF DRUGS IN CROP PROTEC-
TION
Risueño, M.¹* - Corredor, E.¹ - Marquina, C.² - Ibarra, M.R.²
- De La Fuente, J.M.³ - Rubiales, D.4 - Pérez-de-Luque, A.5 -
Testillano, P.S.¹
¹Centro de Investigaciones Biológicas, CSIC
²Inst. Ciencia de Materiales, ICMA, CSIC-Univ. Zaragoza
³Inst. Nanociencia de Aragón, INA, Univ. Zaragoza
4
Inst. Agricultura Sostenible, IAS, CSIC
5
ÍFAPA
*Corresponding author e-mail: risueno@cib.csic.es
The use of nanotechnology for the targeted delivery of substances
has been subject of special attention in biomedicine, being this
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