Meiosis and Development

Research Interests

I use Drosophila melanogaster as a model to study the links between meiosis and oocyte polarity. In Drosophila females, the integrity of the meiotic chromatin is monitored by a checkpoint mechanism whose activation affects gamete viability. Persistent double strand breaks (DSBs) from the meiotic recombination activate a conserved DNA damage response (DDR), which causes reduction in Gurken, a TGF-like ligand necessary to establish the dorsal-ventral (DV) polarity of the eggshell. With a collection of germ line mutations that cause DV polarity defects I will pursue three major lines of research:
1. Characterization of a new DDR pathway that monitors aspects of meiotic progression different from DSB repair. This novel pathway is in parallel to the one already described but converges to the same Gurken production machinery. My work is focused on new components of this pathway and new meiotic mechanisms under surveillance.
2. Dissection of the process that controls timing of DDR along oogenesis. The germ line-specific mobilization of transposable elements is under DDR surveillance. However, the DSBs produced in transposon silencing mutants occur later than the endogenous DSBs. I am interested in responses caused by DNA damage occurring at different points of oogenesis.
3. Study of sister chromatid cohesion during meiosis. Cohesion is also monitored by the meiotic checkpoint and affects the transcriptional state of the chromatin during meiosis. Because cohesion is also required for DNA repair I want to understand how the function of cohesion in transcription relates to DSB repair.
Funding: Marie Curie International Reintegration Grant

Graduate students and posdocs interested in joining this research unit, please send CV and two reference letters to Vitor Barbosa.

Group Members

Patrícia Silva	Research Technician
	Tel: 21 446 4561
Triin Laos	Trainee
	Tel: 21 446 4561
Raquel Santos	2009 PIBS
	Tel: 21 446 4561

Publications

Pimenta-Marques, Tostões, Marty, Barbosa, V., Lehmann, and Martinho (2008). Differential requirements of a mitotic acetyltransferase in somatic and germ line cells Dev Biol 323(2) :197-206

Kunwar, Sano, Renault, Barbosa, V., Fuse, and Lehmann (2007). Tre1 GPCR initiates germ cell transepithelial migration by regulating Drosophila E-cadherin J Cell Biol 183(1) :157-68

Barbosa, V., Kimm, and Lehmann (2007). A maternal screen for genes regulating Drosophila oocyte polarity uncovers new steps in meiotic progression Genetics 176(4) :1967-77

Yohn, Pusateri, Barbosa, V. and Lehmann (2003). l(3)malignant brain tumor and three novel genes are required for Drosophila germ-cell formation Genetics 165(4) :1889-900