title: Comparative analysis of sialidase protein in velogenic and lentogenic strains of Newcastle disease virus.
abstract: The sialidase protein is a  major part of hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV), which is an important multifunctional envelope protein. This protein plays key roles in virus attachment to cells and virus-cell fusion. In this study, we compared the sialidase protein of Iranian virulent velogenic field strains with that of avirulent lentogenic strains. Six of seventeen variations in amino acid 395, 523, 550 432, 479 and 540 were observed near the catalytic and glycosylation sites in the sialidase protein. The obtained results showed fundamental differences in various biological parameters such as post-translational modification, antigenic index and electrostatic potential of tertiary structure of the sialidase protein. We suggest these six amino acids might play an effective role in the pathogenesis of NDV.
authors.forename: M
authors.initials: M
authors.lastname: Esmaelizad
authors.forename: M P
authors.initials: MP
authors.lastname: Ashtiani
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002645:Chickens; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009439:Neuraminidase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D009521:Newcastle Disease / Q000821:virology*; D009522:Newcastle disease virus / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity; D011201:Poultry Diseases / Q000821:virology*; D016415:Sequence Alignment; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D014774:Virulence
chemical_list: D014764:Viral Proteins; D009439:Neuraminidase
keywords: Newcastle disease virus; sialidase; pathogenesis.