Analysis on site variation of amino acid of nucleoprotein of measles virus in Jilin province in 2013

Abstract

Objective To study the site variation of amino acid of nucleoprotein (NP) of measles viruses in Jilin province in 2013.Methods All the throat swab specimen from measles cases in Jilin province in 2013 were detected the NP gene by the reverse transcription-polymerase chain reaction (RT-PCR) and then the RT-PCR positive products were sequenced.To analyze the variation of the deduced amino acid sequence.Results The measles virus genotype in Jilin province in 2013 were H1a genotype.There were 4 amino acids variations in NP in some of 50 specimen in 2013 compared with those of 2001.On the 3 amino acids variations on 422 site(G→S),457 site(S→G),497 site(R→K),there were only very few strains showed variation on these 3 sites in 2001-2008,and there were 100％,76.9％ and 32.0％-32.6％ of strains in 2009,2010 and 2013 respectively which showed variations on these 3 sites.There were 44.0％ of positive specimen of measles virus showed P→S variation only in 2013.Conclusions The measles virus showed diversified variations,remind us to pay close attention to the amino acids variations trend of the NP. Key words: Measles virus; Nucleoproteins; Amino acid sabstitution