A Role for Water Transport in the Regulation of the Optical Power in the Developing Mammalian and Zebrafish Lens: Professor Paul Donaldson and Dr. Irene Vorontsova

Professor Donaldson

Director of the Molecular Vision Research Cluster
University of Auckland

Dr. Irene Vorontsova

Research Fellow
University of Auckland

“A role for water transport in the regulation of the optical power in the developing mammalian and zebrafish lens”

Abstract: In this seminar Professor Paul Donaldson and Dr Irene Vorontsova from the Molecular Vision Research Cluster at the University of Auckland, New Zealand, will each present on their ongoing research into how water transport establishes, maintains, and modulates the refractive power of the ocular lens to ensure that light is corrected focussed on the retina as the eye grows.  Professor Donaldson will first provide an overview of how the adult lens generates an internal microcirculation system that generations a circulating flux of ions and water which has been shown to regulate the optical power of the lens by controlling the volume (geometry) and water to protein ratio (refractive index gradient), the two key factors that determine lens power. He will then discuss how changes to the key proteins (Aquaporin water channels, gap junctions) involved in lens water transport change during the phases of embryonic and postnatal development that occur before eye opening in the mouse lens. Then after eye opening, how the optical properties of the lens change to ensure that light is corrected focussed on the retina as the mouse eye grows.

Dr Vorontsova will then present insights from zebrafish into mechanisms of how water transport mediated by aquaporin 0a (Aqp0a) regulates the formation of lens anatomy and optics and how this system is being utilized to learn about optical development and what may lead to refractive error, such as myopia. Besides determining the water to protein ratio that ultimately determines the refractive index, Aqp0a also regulates the shift of the lens nucleus from an initial anterior location to a central location during development, as well as determines the morphology of the lens sutures – a junction at the poles of the lens where the elongated lens fibre cells meet. By studying the mechanisms that coordinate optical development with axial length, our work will provide not only new insights into normal optical development, but also how its dysfunction can lead to refractive error.

Seminar will be held in person only.