Foster is principal investigator (with professors Lipson and Saranak)
of the grant "Nonlinear Dynamics of Cellular Signal Transduction"
from the National Institutes of Health.
Foster and Jureepan Saranak's overall research goals are to understand
how biological sensors -- in particular light sensors --work, and
how they have evolved over the last few billion years on Earth.
We are studying model cell systems from three major biological Kingdoms:
the Green Alga, Chlamydomonas reinhardtii
Fungal zoospores of Allomyces reticulatus, and
Stramenopiles, Mallomonas and Fucus sperm.
Various aspects are under investigation at different
biological levels. For example, for unicellular vision we are studying
the architecture of its light capturing structure, a dielectric
antenna or eye. At the cellular level, the nonlinear ciliary responses
that enable the cell to use its eye to track the direction of light
are being analyzed. At the intermolecular level, we are employing
systems analysis to describe the network of sensory signals within
a single cell. Some of these signals come from light receptors at
the eye and are used to steer the cell with its cilia. At the molecular
level, we are studying how the light receptor molecules work. Specifically,
we seek the mechanism of activation of the rhodopsin and other G-protein-activating
receptors is being sought. With the conservation of nature, hundreds
of different receptors in human would appear to be in the same superfamily,
first evolved 3.5 billion years ago.
Techniques developed for this work are also being
applied, in collaboration with others, to understand the ubiquitous
pathways by which light can control of gene expression.
Professor Foster is principal investigator (with professors
Lipson and Saranak) of the grant "Nonlinear Dynamics of Cellular
Signal Transduction" from the National Institutes of Health.