Armbrust, E. Virginia. University of Washington, armbrust@ocean.washington.edu
, . Virginia. ,

 
IDENTIFICATION OF GENES EXPRESSED DURING THE ONSET OF SEXUAL REPRODUCTION IN A CENTRIC DIATOM
 
Diatoms are a major component of both marine and freshwater ecosystems. A molecular approach has been taken to identify unique aspects of the diatom life cycle that may help to make these organisms so successful. An intriguing feature of diatoms is that each mitotic division results in the formation of two differently sized daughter cells, one that is the same size as the parent and one that is slightly smaller. Only relatively small cells respond to environmental signals and undergo sexual reproduction, an event that ultimately restores cell size. A PCR-based technique has been used to isolate genes expressed specifically as small cells initiate the sexual cycle. Ten genes unique to sexual cells have been identified thus far. Three of the genes encode related extracellular matrix proteins, which in other organisms are required for cell/cell and cell/substrate adhesion. Because these newly identified cell adhesion-type genes are expressed specifically during the onset of sexual reproduction, they are hypothesized to play a role in sperm/egg recognition. The study of these genes should provide insight into how centric diatom gametes are able to find one another in the dilute environment in which they live.
 
Day: Thursday, Feb. 4
Time: 08:30 - 08:45am
Location: Sweeney Center
 
Code: CS62TH0830S