Annexins are a family of structurally related proteins whose common property is calcium-dependent binding to phospholipids. Although this common property may be due to highly conserved sequences, the existence of at least ten different annexins in the mammalian species suggests that they have specific and diverse biological functions. Specificity and diversity may be carried by the N-termini, different for all annexins, but may also be the consequence of interactions of annexins either with other annexins or other cellular partners. Indeed, the knowledge of the three-dimensional structure of the conserved core of some annexins has not given sufficient understanding of their biological function. To address the issue of the complexity and diversity of the biological functions of annexins, therefore, we wish to investigate the interactions of annexins with other proteins combining the following structural, cell and molecular biology methods:
- preparation of annexins and interactive proteins by recombinant molecular techniques
- production of large quantities of these proteins to a high degree of purity for crystallographic purposes
- X-ray crystallography
- low- and high-resolution electron microscopy
- electrophysiology experiments (patch-clamping and calcium imaging) - static and dynamic fluorescence spectroscopy using synchrotron radiation - search for cellular partners of annexins using the yeast double hybrid system - immunolocalization of proteins within cells
- transfection experiments on the partners for annexins: the overexpression of either a wild type or a mutated form of the partner.
With the following aims:
- the 3D structure determination of intact annexin molecules. - characterization of annexins in solution.
- study of interactions between annexins and other proteins. - analysis of the formation of annexin homo- and hetero-complexes. - analysis of the biological function of annexin homo- and hetero complexes. - exploitation of our results for medical purposes.
The partners in the project have all worked in the field of annexins, or related proteins, for several years. By combining our efforts we hope to advance much faster toward the common goal of better understanding of how annexins regulate diverse activities in complex multicellular organisms, and by correlating annexin structure with function, we hope to contribute to the design of novel therapeutic strategies for the treatment of inflammatory and cardiovascular diseases. Furthermore, we hope to promote exchanges between our groups and, where possible, join forces in training young people across national borders.
Funding SchemeCSC - Cost-sharing contracts
82152 Planegg / Krailling
6747 AG Groningen