Ff. Maree et H. Huismans, CHARACTERIZATION OF TUBULAR STRUCTURES COMPOSED OF NONSTRUCTURAL PROTEIN NS1 OF AFRICAN HORSESICKNESS VIRUS EXPRESSED IN INSECT CELLS, Journal of General Virology, 78, 1997, pp. 1077-1082
The characteristic tubules that are produced during the orbivirus infe
ction cycle are composed of a major viral nonstructural protein, NS1.
To characterize the NS1 gene and gene product of African horsesickness
virus (AHSV), a full-length cDNA copy of the NS1 gene of AHSV-6 was c
loned and the nucleotide sequence determined. NS1 was highly conserved
within the AHSV serogroup with between 95-98% conservation of amino a
cids among NS1 of AHSV-6, AHSV-4 and AHSV-9. The structure of AHSV NS1
tubules was investigated by in vitro translation of the AHSV-6 NS1 ge
ne followed by expression of the gene in insect cells. The NS1 protein
assembled in tubular structures with a diameter of approximately 23 n
m and lengths of up to 4 mu m. The absence of a ladder-like structure
and lower sedimentation value of AHSV NS1 tubules clearly distinguishe
d them from those of bluetongue virus.