2009 Dance Your Ph.D. Winner (Graduate Student - Sue Lynn Lau)

PhD title: The role of Vitamin D in beta-cell function.

Graduate student: Sue Lynn Lau

Performers: Members of the Diabetes & Transcription Factors Lab Group

Synopsis: Every PhD begins in the dark, but it takes only a few bright sparks to kindle the flame of discovery...

The crucial role of sunlight exposure as the most important source of vitamin D in humans is highlighted. Vitamin D is newly recognised to be involved in the function of many organ systems, including the beta cells of the endocrine pancreas. These cells make insulin in response to glucose stimulation.

Initially, the beta cells are in an unstimulated state, with minimal activity. At the arrival of the sugar plum fairy (symbolising glucose), the cells are able to sense the presence of glucose through the enzyme glucokinase. When glucose enters the cells through glut 2 transporters (marshmallow feeding), it is metabolised to produce the energy molecule, ATP. Through a number of steps, this leads to a rise in positive charge inside the cell, which ultimately triggers the export of insulin-storing granules by a process known as exocytosis (depicted here by the blowing of bubbles). Normal insulin secretion requires the coordinated function of beta cells via intercellular connections and communications as they work in concert.

We are investigating whether vitamin D has an effect in improving beta-cell function and increasing insulin secretion... are they "walking on sunshine"??