The major structural polypeptide of rotaviruses is p45K (VP6), which forms the morphological subunit of the inner capsid. Such subunits show a trimeric structure when examined with the electron microscope. Treatment of single-capsid rotavirus particles with 1.5 m-CaCl2 removes p45K, resulting in the generation of smooth cores. Sucrose density gradient centrifugation analysis of the removed p45K revealed that it has a sedimentation coefficient close to 7.3S, compatible with an oligomeric (possibly trimeric) structure. Polyacrylamide gel electrophoresis under reducing or non-reducing conditions indicated that p45K has intramolecular but not intermolecular disulphide bonds, suggesting that interactions between p45K monomers may be due to some other type of association, such as hydrophobic or charge interactions. Velocity sedimentation of infected cell extracts revealed that native p45K also behaves as an oligomeric protein. Such results were confirmed using p45K partially purified by DEAE-cellulose chromatography. The evidence obtained indicated that all p45K present in the virion is in the oligomeric form, not associated by disulphide bonding, and that most native p45K present in the infected cells is also in the oligomeric form, probably as a consequence of early protein-protein interaction in rotavirus morphogenesis.
AlloreR. J.,
BarberB. H.1984; A recommendation for visualizing disulphide bonding by one-dimension sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Analytical Biochemistry 137:523–527
AlmeidaI. D.,
HallT.,
BanatvalaJ. E.,
TotterdellB. M.,
ChrystieI. L.1978; The effect of trypsin On the growth of rotavirus. Journal of General Virology 40:213–218
BastardoJ. W.,
Mckimm-BreschkinJ. L.,
SonzaS.,
MercerL. D.,
HolmesI. H.1981; Preparation and characterization of antisera to electrophoretically purified SA 11 virus polypeptides. Infection and Immunity 34:641–647
BothG. W.,
SiegmanL. J.,
BellamyA. R.,
IkegamiN.,
ShatkinA. J.,
FuruichiY.1984; Comparative sequence of rotavirus genomic segment 6 – the gene specifying viral subgroups 1 and 2. Journal of Virology 51:97–101
ChaseyD.,
LabramJ.1983; Electron microscopy of tubular assemblies associated with naturally occurring bovine rotavirus. Journal of General Virology 64:863–872
EricsonB. L.,
GrahamD. Y.,
MasonB. B.,
EstesM. K.1982; Identification, synthesis and modification of simian rotavirus SA 11 polypeptides in infected cells. Journal of Virology 42:825–839
EsparzaJ.,
GorzigliaM.,
GilF.,
RomerH.1980; Multiplication of human rotavirus in cultured cells: an electron microscopic study. Journal of General Virology 47:461–472
EstesM. K.,
MasonB. B.,
CrawfordS.,
CohenI.1984; Cloning and nucleotide sequence of the simian rotavirus gene 6 that codes for the major inner capsid protein. Nucleic Acids Research 12:1875–1887
LeeP. W. K.,
HayesE. C.,
JoklikW. K.1981; Characterization of anti-reovirus immunoglobulins secreted by cloned hybridoma cell lines. Virology 108:131–146
PalmerE. L.,
MartinM. L.,
MurphyF. A.1977; Morphology and stability of infantile gastroenteritis virus: comparison with reovirus and bluetongue virus. Journal of General Virology 35:403–414
PerssonH.,
ObergB.,
PhilipsonL.1978; Purification and characterization of an early protein (E 14K) from adenovirus type 2 infected cells. Journal of Virology 28:119–139
PowellK. F. H.,
HarveyJ. D.,
BellamyA. R.1984; Reovirus RNA transcriptase: evidence for a conformational change during activation of the core particle. Virology 137:1–8
TheilK. W.,
BohlE. H.,
AgnesA. G.1977; Cell culture propagation of porcine rotavirus (reovirus-like agent). American Journal of Veterinary Research 38:1765–1768