organisation - the Instituto Gulbenkian de Ciência

EVOLUTION
AND DEVELOPMENT
Élio Sucena Principal Investigator
PhD in Evolution and Development, Genetics, Cambridge, UK, 2001
Post-Doc at Princeton University, USA
Post-Doc at University of Western Ontario, Canada
Liaison with the Champalimaud Foundation
Principal Investigator at the IGC since 2003
Research in my lab focuses on evolutionary novelties, defined as a novel body
part that is neither homologous to any body part in the ancestral lineage nor
serially homologous to any other body part of the same organism. This concept
can be extended to other traits, for example, physiological or behavioural.
We have identified several instances of novelty, as defined above, that we are
experimentally dissecting:
1. At the genetic level, looking at gene function evolution upon gene duplication;
2. At the cellular level, approaching immune cell function diversity in Drosophila;
3. At the morphological level by studying the evolutionary origin of dorsal
appendage formation in the Drosophila clade.
DISSECTING THE DEVELOPMENTAL GENETIC BASIS OF EVOLUTIONARY NOVELTY
The eggshell's dorsal appendages are structures unique to the Drosophila lineage,
found throughout the lineage in various numbers, shapes and sizes. With
Adrien Fauré and Claudine Chaouiya we have progressed in the establishment
of a model that recapitulates the epithelial patterning, and with which we are
now able to explore the variation in number this structure displays across Drosophila
species. In addition, our research into eggshell patterning of Ceratitis
capitata, a species without dorsal appendages outside of the Drosophila clade,
has led to a renewed understanding of the role played by the Dpp pathway
during oogenesis. With the combination of these two lines of research we continue
to investigate both the possible origin as well as the diversification of this
evolutionary novelty.
GROUP MEMBERS
Nelson Martins (Post-doc)
Kohtaro Tanaka (Post-doc, started in May)
Alexandre Leitão (PhD student)
Barbara Vreede (PhD student)
Vítor Faria (Research Assistant)
COLLABORATORS
Jen Sheen (Massachusetts General Hospital, USA)
Mark Borowsky (Massachusetts General Hospital, USA)
Brad Chapman (Massachusetts General Hospital, USA)
Ignacio Rubio Somoza, (Max Planck Institute for Developmental Biology,
Germany)
Detlef Weigel (Max Planck Institute for Developmental Biology, Germany)
Pedro L. Rodriguez Egea (Instituto de Biología Molecular y Celular
de Plantas, Universidad Politécnica de Valencia, Spain)
Markus Teige (Max F. Perutz Laboratories, Univ. Vienna, Austria)
Andreas Bachmair (Max F. Perutz Laboratories, Univ. Vienna, Austria)
Claudine Chaouiya (IGC, Portugal)
Adrien Fauré (IGC, Portugal)
Thiago Carvalho (IGC, Portugal)
Jocelyne Demengeot (IGC, Portugal)
Luis Teixeira (IGC, Portugal)
Fernando Roch (Centre de Biologie et Developpement, France)
Sara Magalhães (Faculdade de Ciências, Universidade de Lisboa, Portugal)
FUNDING
Fundação para a Ciência e a Tecnologia (FCT), Portugal
Instituto Gulbenkian de Ciência (IGC), Portugal
Comparing the patterning network of Drosophila with a species without dorsal
appendages, the mediterranean fruitfly Ceratitis capitata, has pointed us
toward a key node in the network: the gene mirror. This transcription factor is
absent in Ceratitis oogenesis, but performs a key function in defining the cells
that make up the dorsal appendages, as well as defining the dorso-ventral axis
of the future Drosophila embryo. We are currently exploring this co-option in
more detail.
FUNCTIONAL EVOLUTION UPON GENE DUPLICATION
We have been studying a recently expanded gene family in Drosophila, the
Three Finger Domain Protein (TFDP), in particular the nine genes of clusters III
and V. Given their expression patterns in the Drosophila eye disc, we hypothesise
that, in higher Diptera, TFDP genes have been co-opted by the ancestral
eye development gene network. Different genes of this recently expanded family
have been deployed in specific glial/neural cell subsets as to participate in
the highly dynamic process leading to the formation of both photoreceptor
axonal tracks and their respective myelin sheaths. This study establishes the
TFDP gene family evolution as an example of neo/sub-functionalisation by gene
duplication. Further work will clarify the specific impact of regulatory evolution
over the gene network driving the cellular mechanisms in the developing eye of
holometabolous insects.
In order to have a comprehensive description of expression pattern evolution
of these nine TFDP genes in Drosophila, we extended our analysis to Tribolium,
Anopheles, Megaselia and Ceratitis. With this wide phylogenetic coverage, we have
a clear idea of the duplication history of these genes and hence a strong basis to
define instances of sub- and neo-functionalisation for future promoter dissection.
IMMUNE CELL FUNCTION DIVERSITY IN DROSOPHILA
We had previously shown that, contrary to the current view, Drosophila plasmatocytes
(the functional analogues of vertebrate macrophages) constitute a
heterogeneous population. For this we have established a novel protocol for
PARASITOID WASP EGG SURROUNDED BY HOST IMMUNE CELLS (PLASMATOCYTES).
Heterogeneity of plasmatocyte population is apparent by the differential expression
of green (Cg25C) and red fluorescence (eater).
IGC ANNUAL REPORT ‘11
RESEARCH GROUPS
62