Oocyte Biology & Cellular Dormancy

Oocyte Biology & Cellular Dormancy

Cell and Developmental Biology

Oocyte Biology & Cellular Dormancy

Group leader
j

Oocyte Biology & Cellular Dormancy

Group leader
j

2008-2012  Graduate Student at Cancer Research UK Manchester Institute (CRUK-MI), Manchester, UK.
2013-2016 Postdoctoral Fellow at the Department of Systems Biology,  Harvard Medical School, Boston, USA. 
January 2017 Group Leader in the Cell & Developmental Biology programme at the Centre for Genomic Regulation, Barcelona, Spain.

Summary

Oocytes, female germ cells that become eggs, are highly specialized cells. They ensure the continuity of species by providing the female genome and mitochondria along with most of the nutrients and housekeeping machinery the early embryo needs after fertilisation. Oocytes are remarkable in their ability to survive for long periods of time, up to 50 years in humans, and retain the ability to give rise to a young organism while other cells age and die.

A key feature of dormant oocytes of virtually all vertebrates is the presence of a Balbiani body, which is a non-membrane bound compartment that contains most of the organelles in dormant oocytes. The Balbiani body can be thought of as a “super-organelle” that clusters other organelles. It is stable only in the dormant oocytes, and disperses upon oocyte activation.

 

Balbiani bodies, labeled “BB” in these images of an immature frog egg (left) and immature human egg (right, larger scale), hold organelles together in one spot next to the nucleus, “n,” in the months or years before an egg matures. Images: Elvan Boke (left), Arthur Hertig (right)

 

Our long term goal is to reveal the mechanisms dormant oocytes employ to remain viable.  My previous research has shown that the Balbiani body forms an amyloid-like cage around organelles that could be protective. This work suggests a number of outstanding problems to investigate, both in the nature of oocyte organelles, and the regulation of amyloid-like structures. We will initially focus on three interlinked directions, which focus on how organelles are organized and how their metabolism is regulated in the dormant oocyte:

1) What is the metabolic nature of organelles in dormant oocytes?

2) How does the Balbiani body disassemble and release the complement of organelles when oocytes start to mature?

3) What is the structure and function of the Balbiani body in mammals?

We use oocytes from two vertebrate species, frogs and mice, which are complementary for their ease of handling and relationship to human physiology. 

Our research has implications both for the structure and function of vertebrate organelles, and the regulation of physiological amyloid-like structures. More generally, it opens up new avenues into the mechanisms that protect organelles from ageing and how oocytes stay dormant for many decades.