Interaction of the myristoylated M-PMV matrix protein and his mutants with phospholipids

Tomáš Kroupa^1,2, Ladislav Bumba³, Michal Doležal², Jan Prchal², Richard Hrabal²

¹Department of Biochemistry and Microbiology, Institute of Chemical Technology,

Technická 5, 166 28 Prague 6, Czech Republic

²Laboratory of NMR Spectroscopy, Institute of Chemical Technology,

Technická 5, 166 28 Prague 6, Czech Republic

³Institute of Microbiology, Academy of Sciences of the Czech Republic,

Vídeňská 1083, 142 20 Prague 4, Czech Republic

tomas.kroupa@vscht.cz

Mason-Pfizer monkey virus (M-PMV) is widely used as a model organism for studies of the late phase of the retroviral life cycle. Matrix protein forms the N-terminus of a polyprotein Gag and plays key role in the transport of the immature viral particle (IVP) to the cell membrane and in its interaction with membranes. Previous studies suggest that matrix protein interacts with the phospholipids of the cell membrane and thus allows budding of the IVP. This work focuses on the interaction of the matrix protein with the main components of the cell membrane: phosphatidylcholine, phosphatidylserine, phosphatidylethanolamine and, the marker of the cytoplasmic membrane, phosphatidylinositol-4,5-bisphosphate. The wild type matrix protein and his two mutants (T41I/T78I and Y28F/Y67F) were used. Both mutants have decreased budding capability, which could be explained by their impaired interaction with the cell membrane. We studied the interaction by a combination of surface plasmon resonance (SPR) and nuclear magnetic resonance (NMR).