TY - JOUR
T1 - In vitro assembly of virus-like particles of a gammaretrovirus, the murine leukemia virus XMRV
AU - Hadravová, Romana
AU - de Marco, Alex
AU - Ulbrich, Pavel
AU - Štokrová, Jitka
AU - Doležal, Michal
AU - Pichová, Iva
AU - Ruml, Tomáš
AU - Briggs, John A.G.
AU - Rumlová, Michaela
PY - 2012/2
Y1 - 2012/2
N2 - Immature retroviral particles are assembled by self-association of the structural polyprotein precursor Gag. During maturation the Gag polyprotein is proteolytically cleaved, yielding mature structural proteins, matrix (MA), capsid (CA), and nucleocapsid (NC), that reassemble into a mature viral particle. Proteolytic cleavage causes the N terminus of CA to fold back to form a β-hairpin, anchored by an internal salt bridge between the N-terminal proline and the inner aspartate. Using an in vitro assembly system of capsid-nucleocapsid protein (CANC), we studied the formation of virus-like particles (VLP) of a gammaretrovirus, the xenotropic murine leukemia virus (MLV)-related virus (XMRV). We show here that, unlike other retroviruses, XMRV CA and CANC do not assemble tubular particles characteristic of mature assembly. The prevention of β-hairpin formation by the deletion of either the N-terminal proline or 10 initial amino acids enabled the assembly of ΔProCANC or Δ10CANC into immature-like spherical particles. Detailed three-dimensional (3D) structural analysis of these particles revealed that below a disordered N-terminal CA layer, the C terminus of CA assembles a typical immature lattice, which is linked by rod-like densities with the RNP.
AB - Immature retroviral particles are assembled by self-association of the structural polyprotein precursor Gag. During maturation the Gag polyprotein is proteolytically cleaved, yielding mature structural proteins, matrix (MA), capsid (CA), and nucleocapsid (NC), that reassemble into a mature viral particle. Proteolytic cleavage causes the N terminus of CA to fold back to form a β-hairpin, anchored by an internal salt bridge between the N-terminal proline and the inner aspartate. Using an in vitro assembly system of capsid-nucleocapsid protein (CANC), we studied the formation of virus-like particles (VLP) of a gammaretrovirus, the xenotropic murine leukemia virus (MLV)-related virus (XMRV). We show here that, unlike other retroviruses, XMRV CA and CANC do not assemble tubular particles characteristic of mature assembly. The prevention of β-hairpin formation by the deletion of either the N-terminal proline or 10 initial amino acids enabled the assembly of ΔProCANC or Δ10CANC into immature-like spherical particles. Detailed three-dimensional (3D) structural analysis of these particles revealed that below a disordered N-terminal CA layer, the C terminus of CA assembles a typical immature lattice, which is linked by rod-like densities with the RNP.
UR - http://www.scopus.com/inward/record.url?scp=84857098150&partnerID=8YFLogxK
U2 - 10.1128/JVI.05564-11
DO - 10.1128/JVI.05564-11
M3 - Article
C2 - 22090120
AN - SCOPUS:84857098150
VL - 86
SP - 1297
EP - 1306
JO - Journal of Virology
JF - Journal of Virology
SN - 0022-538X
IS - 3
ER -