Very little is known about how oocyte identity is established.Unlike somatic cells, oocyte specification occurs not at the single cell level, but inside a cyst of interconnected germ cells, only one or a few of which become oocytes, in a process that relies on intercellular transport between germ cells. This makes it difficult to model oocyte specification in vitro, particularly in mammals, where differentiation occurs in a short time window shortly before birth. Drosophila provides a unique in vivo model system to study the phylogenetically conserved principles of oocyte specification, since germline cyst formation and oocyte specification occur continuously in adult females, allowing the observation and genetic manipulation of all stages of the cyst development and oocyte selection. In Drosophila, oocyte selection depends on the formation of a polarised noncentrosomal microtubule network that directs dynein-dependent transport of oocyte fate determinants into only one cell of the cyst. My research in St Johnston group at Gurdon Institute focuses on understanding molecular mechanisms behind germline cyst polarisation and oocyte fate determination.
