STRUCTURAL INVESTIGATION OF DISTINCT SPECIFICITY OF TWO ISOFORMS OF RAT RECEPTOR NKR-P1
O. PLÍHAL^1,2, L. MIHÓK², R. ETTRICH³, P. MAN^1,2, V. HAVLÍČEK², P. BYRTUSOVÁ¹, J. PAVLÍČEK¹, K. BEZOUŠKA^1,2

¹Department of Biochemistry, Faculty of Science, Charles University Prague, Hlavova 8, CZ-12840 Prague 2, Czech Republic

²Institute of Microbiology, Academy of Sciences of Czech Republic, Vídeňská 1083, CZ-14220 Prague 4, Czech Republic

³ Laboratory of High Performance Computing, Institute of Physical Biology USB and Institute of Landscape Ecology AS CR, Zámek 136, CZ-37333 Nové Hrady, Czech Republic

Receptor NKR-P1 is one of lectin-like proteins on the surface of rat lymphocytes [1]. Unique isoforms of this receptor can have both activating and inhibitory function in the process of killing of tumor or virus-infected cells. The isoform NKR-P1A is activating receptor, whereas the isoform NKR-P1B has an inhibitory activity. However, the primary sequence of both proteins is very similar. We can conclude from the results of binding experiments with recombinant extracellular portions of both isoforms, that monosacharide specificity of these proteins are the same. On the other hand, we can observe a principal difference if we compare the results of binding experiments with oligosaccharides and glycodendrimers [2]. We use computer modelling to suggest structural basis of such diversity and try to find possible functional implications.

References:

[1] Yokoyama W. M. Curr. Biol., 5 (1995) 982.

[2] Plíhal O. et al., Collection Czech Chem. Commun., in press.