INTAS-01-0045
Molecular
interactions of a plant virus genome with virus-coded and host cell
proteins involved in intercellular virus transport: high-resolution
imaging of protein-protein and protein-RNA complexes
Project
Co-ordinator Prof. Michael Taliansky
General
description
Virus-encoded
movement proteins (MP) are essential for cell-to-cell translocation
of plant viral genomes. It is widely believed that intra- and intercellular
trafficking of viral MP and transport RNP non-virion (MP-RNA) or virion
(CP-RNA) complexes depend on their interactions with cellular receptors,
the MP-binding proteins (MPBPs). The proposed interdisciplinary research
will identify and characterize the architecture and structure of cellular
MPBPs complexes with viral MPs and transport RNP complexes by atomic
force microscopy (AFM) and Biacore system, and elucidating the changes
in the structure of complexes following phosphorylation in relation
to their functions.
These
include:
- Complexes
formed by the MPs and host-plant-coded MPBPs.
-
Purified MPBPs, in particular, the pectin methylesterase (PME).
-
Complexes formed by MPBPs and "MP-RNA" ribonucleoproteins (RNPs).
-
Nontranslatable non-virion "MP-RNA" or virion "CP-RNA" RNP-complexes,
and the same RNPs converted into a translatable form after phosphorylation
of the MP (or CP).
-
Native and phosphorylated viral genome-linked protein (VPg) exposed
on the surface of the potato virus A. A putative complex formed by
the virion VPg with cellular proteins.
Research
Programme
Task
1.
To
image and measure by AFM the structure of cellular MPBPs, their complexes
with viral MPs and nucleoprotein transport complexes (MP-RNA and CP-RNA)
formed in vitro.
Task
2. To
study by AFM the structural changes induced upon translational activation
of: (i) TMV MP-RNA and encapsidated PVX RNA by proteins phosphorylation;
(ii) encapsidated PVX RNA by binding the TGBp1 MP molecules to one
end of the virions.
Task
3. To
visualize by AFM and/or by cryoelectron microscopy the location of
VPg on the surface of PVA potyvirus virions and the complexes formed
by the virion VPg with cellular proteins; to study the effect of VPg
phosphorylation on the structure of virus particles and RNA translatability.
Task
4. The aims are to determine the
rate of association and dissociation of complexes and the effects
of modifications on binding strength and complex stability.
Participating
teams
1.
Scottish
Crop Research Institute, Division
of Pathology, Unit of Virology
team leader Prof.
Michael Taliansky
2. University
of Helsinki, Institute
of Biotechnology
team leader Dr. Kristiina Makinen
3. M.V.Lomonosov
Moscow State University, Plant
Virology Department
team leader Prof. Josheph Atabekov
4. Advanced
Technology Center
team leader Dr. Olga Kiselyova
5. Centre
of Bioengineering, Laboratory
of Genetic Engineering
team leader Prof. Konstantin
Skryabin