Postdoctoral position in electrophysiology
Biology Department, Lancaster University, UK
Applications are invited for a post-doctoral position for 2 years.
The project will take advantage of recent advances in the use of the
yeast Pichia pastoris as a heterologous protein expression system to
investigate the kinetic properties of K+ and Ca2+plant transporters.
Applicants should have experience or an interest in electrophysiology
and ion transport across membranes. Applicants should have, or expect to
have, a PhD or equivalent in an appropriate discipline.
Salary: according to qualifications and experience.
Closing date: 02/07/02
Informal enquiries to Dr Stephen Roberts (s.k.roberts at lancaster.ac.uk)
or Professor Brian G. Forde (b.g.forde at lancaster.ac.uk).
This is a fixed term post, funded by the BBSRC, for a maximum of 2
years. The post will be in the Department of Biological Sciences at
Lancaster University under the supervision of Dr S. Roberts and
Professor B. G. Forde.
Ion transporters play important roles in many diverse aspects of cell
biology and physiology. Insights into these processes therefore require
a detailed understanding of the molecular mechanisms and regulatory
controls which determine the activity of these transporters. In recent
years, major advancements have been made in the understanding of
transporters using a combination of electrophysiological and molecular
biological techniques. Of particular importance has been the cloning of
ion transporters and the use of heterologous expression systems in which
isolated transporters are functionally studied using
In animal research, much success has been achieved by the functional
expression and electrophysiological characterisation of transporters in
Xenopus oocytes and, to a lesser extent, cell cultures. However, the use
of animal expression systems has been much less successful for the
investigation of plant and fungal transporter with a number of reports
that a variety of transporters fail to express functionally. By
contrast, the budding yeast, Saccharomyces cerevisiae, has been
considerably more successful for the expression of plant and fungal
transporters than either of the animal expression systems. However, the
inability to gain sufficient level of expression in yeast cells has
often precluded functional analysis of many plant and fungal
transporters using electrophysiological techniques.
The present proposal aims to take advantage of the much higher
expression levels which can be attained using the methylotropic yeast,
Pichia pastoris, to allow the electrophysiological characterisation of
transporters which, to date, has not been possible. The project will
focus on the characterisation of two cloned plant transporters (HvHAK
and LCT1) for which there is no electrophysiological analysis of
transporter activity. However, the development of the patch clamp
technique for its application to Pichia pastoris will provide a unique
opportunity to investigate the biophysical properties of a wide variety
of transporter types.