Toshie KAI, Ph.D, Senior Principal Investigator

Toshie Kai obtained her university diploma (1993) and doctoral degree (1998) at Osaka University in Japan.  She spent her postdoc years in the laboratory of Dr Allan Spradling (Carnegie Institution/ Howard Hughes Medical Institute). In 2005, she joined Temasek Life Sciences Laboratory as Principal Investigator and established the Germ Line Biology Group.

You may wish to contact Dr Toshie KAI at:

Tel: (65) 6872 7000, 6872 7425 (DID) or 6872 7426 (lab) Email: toshie@tll.org.sg

For information on PhD studies at TLL, click HERE

Research Interests

• Function of nuage
• biogensis of piRNA
• regulation of gametogenesis by nuage

Research Projects

The most important cell lineage for the survival of sexually reproducing metazoans is the germline, due to its unique role in gamete production and species continuity. Although the extensive analysis has been done with the model organisms, such as Drosophila, it remains unclear what confers such a special nature. In order to unveil the nature of germline cells, we’re focused on the nuage, an electron-dense perinuclear structure known to be a hallmark of animal germline cells. The nuage forms an amorphous and fibrous structure that is localized to the cytoplasmic face of the nuclear envelope when visualized by electron microscopy. Although the nuage was reported more than a half century ago, its role(s) and the mechanism(s) by which it functions in the animal germ line remained unknown.

Previously we reported a novel nuage component, Krimper (KRIMP), in Drosophila melanogaster and showed that it ensures the repression of the selfish genetic elements in the female germ line. Selfish genetic elements are mobile RNA elements, which can lead to genome-wide transposition and therefore, result in genome instability. Our previous work, together with recent findings by other groups, has demonstrated that retroelement silencing involves a unique class of germline-specific small RNAs, termed the Piwi-associated small interfering RNAs (piRNAs). Our working model is that, nuage may be the compartment where piRNA are processed. Currently our projects are focused on the molecular function of nuage in some aspects including the role(s) in the production of piRNAs during oogenesis and spermatogenesis.