Biology Reference
In-Depth Information
Fig. 2.
Structures of the carboxyl-terminal regions in VP1-pentamer.
(
A
)C-
backbone drawing of SV40 virion reconstructed from the structural
unit of the SV40 VP1 capsid (1SVA) using VIPER. Pentavalent VP1-pen-
tamers (VP1-pentamers surrounded by five VP1-pentamers) are marked in
light blue. The C-terminal arm regions, VP1(301-312), (313-329), (330-
344) and (345-361), are colored in red, green, yellow, and purple, respec-
tively. The positions of three distinct interaction-types of the C-terminal arm
in the SV40 particle are shown in (
B
) (
α
α
′
α
′′
β
′
α
-
-
), (
C
) (
β
-
), and (
D
)(
γ
-
γ
).
VP1-partner. X-ray crystallographic data of the C-terminal portion of
the polyomavirus VP2 (residues 269-296) showed that the C-terminus
of VP2/3 associates with VP1-pentamer tightly and specifically through
hydrophobic interactions.
8
The larger N-terminal part of the internal
protein is flexible and sensitive to gentle proteolysis. At the center of the
virion, it locates the virus genome as minichromosome arranged with
histones electron density at the center of the SV40 is smeared, suggest-
ing that the minichromosome is not organized with icosahedral sym-
metry matching the capsid symmetry (Fig. 3).
9
