Title |
Phosphorylation of the nucleocapsid protein of Hantaan virus by casein kinase II |
Author |
Jeong-Joong Yoon1, Yun-Tai Lee2, Hin Chu3, Seung-yeol Son2, and Manbok Kim4* |
Address |
1Department of Microbiology, Dankook University Graduate School, Cheonan 330-714, Republic of Korea, 2Department of Microbiology, School of Natural Sciences, Dankook University, Cheonan 330-714, Republic of Korea, 3Department of Microbiology, The University of Hong Kong, Hong Kong Special Administrative Region, P. R. China, 4Department of Medical Science, Dankook University College of Medicine, Cheonan 330-714, Republic of Korea |
Bibliography |
Journal of Microbiology, 53(5),343-347, 2015,
|
DOI |
10.1007/s12275-015-5095-3
|
Key Words |
Hantaan virus, nucleocapsid protein, phosphorylation,
casein kinase II |
Abstract |
Hantaanvirus (HTNV) is the prototype of the genus Hantavirus,
which belongs to the family Bunyaviridae. Hantaviruses
are carried and transmitted by rodents and are known to
cause two serious disease syndromes in humans i.e., hemorrhagic
fever with renal syndrome (HFRS) and the hantavirus
pulmonary syndrome (HPS). HTNV is an enveloped
virus that contains a tripartite genome consisting of three
negative-sense RNA segments (L, M, S), and the S and M
segment of HTNV, respectively, encode the viral nucleocapsid
protein (NP) and envelope glycoproteins. Possible
phosphorylation motifs of casein kinase II (CKII) and protein
kinase C (PKC) were identified in HTNV NP through
bioinformatics searches. Sucrose gradient SDS-PAGE analysis
indicated that dephosphorylated HTNV NP migrated
faster than non-dephosphorylated NP, suggesting that HTNV
NP is phosphorylated in infected Vero E6 cells. Immunoblot
anaylsis of HTNV particles with anti-phosphoserine antibody
and anti-phosphothreonine antibody after immunoprecipitation
showed that viral particles are readily phosphorylated
at threonine residues. In vitro kinase assay further
showed that HTNV NP is phosphorylated by CK II,
but not by PKC. Full length or truncated HTNV NPs expressed
in E. coli were phosphorylated in vitro by CKII suggesting
that phosphorylation may occur in vivo at multiple
sites. Site specific mutagenesis studies suggest that HTNV
NP phosphorylation might occur at unknown sites excluding
the site-directly mutagenized locations. Taken together,
HTNV NP can be phosphorylated mainly at threonine residues
in vivo by CK II treatment. |