Structural biology: A gallery of protein pumps

An international team of structural biologists has created some of the most detailed images yet of three proteins that help cells shuttle charged ions across their membranes - an important process in maintaining intracellular stores of these chemicals.

The researchers, divided into three research groups, each of which is led by Poul Nissen, have used a technique called X-ray crystallography to study the structures of three different ‘ion pumps’ with unprecedented resolution - down to the level of individual atoms within these protein complexes. The research will provide more detailed insight into the structure of these pumps, each of which break down the energy-giving molecule ATP to force ions across membranes against a concentration gradient.

In three separate research papers Nissen and colleagues unveil the structures of: the proton pump, which shuttles hydrogen ions across cell membranes in plants and fungi; the calcium pump, which moves calcium ions into cellular storage compartments and is essential for muscle function; and the sodium-potassium pump, which is important for a range of functions including transmission of nerve impulses along neurons.

The researchers report several unexpected properties of these protein complexes, including the remarkable similarity shared by the calcium and sodium-potassium pumps, which raises the question of how they manage to bind specifically to these different ions.

CONTACT
Poul Nissen (University of Aarhus, Denmark) Author papers [6], [7] & [8]
Tel: +45 8942 5025; E-mail: pn@mb.au.dk

David Gadsby (Rockefeller University, New York, NY, USA) (N&V Author)
Tel: Please check on the press site for updates
E-mail: gadsby@mail.rockefeller.edu