SECONDARY STRUCTURE PREDICTION OF THE HEMAGGLUTININ-NEURAMINIDASE FROM A PORCINE RUBULAVIRUS

The Hemagglutinin-Neuraminidase (HN) from 'La Piedad, Michoacan' porci ne rubulavirus (LPMV) interacts specifically with NeuAc alpha 2,3 lact ose residues on the target cell. In this work we report the secondary structure of this protein, determined with five different theoretical algorithms. Results indicate that the HN protein is organized in: an i ntracellular region (from amino acid 1 to 25); in a beta-strand transm embrane region (residue 26 to 47), typically hydrophobic, rigid and so lvent inaccessible; and extracellular region (residue 48 to 576), whic h possesses hemagglutinating and neuraminidase activity. The secondary structure in this region is organized in a beta-loop-beta alternated with few alpha-helices. Regions with structural and functional implica tions were determined by pattern search and multiple alignment of the HN from LPM with 12 rubulaviruses and paramyxoviruses HN sequences. Th e low diversity observed among the HN sequences evaluated indicates th at in general the structural organization of the protein, and in parti cular its sugar binding domain, is closely related among both genera, thus suggesting that the sugar binding domain is well preserved throug h evolution.