High-resolution structure of extracellular domain of human CD69

P. Kolenko^1,2, O. Vaněk³, T. Skálová², J. Dohnálek², J. Dušková², A. Štěpánková, K. Bezouška³, J. Hašek²

¹Dept. of Solid State Engineering, FNSPE CTU, Trojanova 13, 120 00 Praha 2

²Institute of Macromolecular Chemistry AS CR, Heyrovského nám. 2, 162 06 Praha 6

³Dept. of Biochem., Faculty of Science, Charles University in Prague, Hlavova 8, 12840 Praha 2

kolenko@imc.cas.cz

Natural killer cells a are part of our innate immune defense able to kill several types of tumor cells. Their activity is regulated by activation or inhibition signals coming from receptors expressed on cell surface. Studies of these receptors provide novel insights into the mechanisms of function of natural killer cells.

The extracellular domain of human CD69 was crystallized using novel polymer screens [1]. The crystals belonging to space group P6₁ diffracted to high resolution (1.37 Å) and were merohedrally twinned. The structure provides the most detailed information on intra- and intermolecular interactions of the human CD69 receptor. A comparative analysis of CD69 including homologous structures is performed.

CD69 belongs to the earliest induced cell surface glycoproteins during natural killer cell activation. Recombinant forms of the extracellular part of the receptor can be potentially used in cancer treatment. However, the mechanism of function of the molecules still remains unclear in spite of the fact that many biochemical and biophysical studies were reported [2].

Acknowledgement

This work was supported by GA AV IAA500500701, GA ČR 305/07/1073 and European Commission Integrated project SPINE2-Complexes, no. 031220.

References

1. J. Hašek, J. Dohnálek, J. Dušková, T. Skálová, P. Kolenko, T. Koval, A. Štěpánková, Acta Cryst., A64, (2008), C233.

2. O. Vaněk et al., FEBS Journal, 275, (2008), 5589.