AFM OF RNA AND RNA-PROTEINS COMPLEXES

O.I. Kiselyova

Joint SPM Group,
Moscow State University & Advanced Technologies Center
 
      By means of AFM we studied RNA-protein interactoin in RNA-containing tobacco mosaic virus (TMV): TMV RNA release from virus capsid and TMV-coded movement protein (MP) complexes with TMV RNA.
     It was found out that:
  • TMV RNA-MP complexes and RNA protruded from partly uncoated TMV particles can be visualized on freshly cleaved mica
  • Length distribution of denatured TMV RNA visualized on mica has 3 peaks: 0.7 microns, 1.4 microns and 2.0 microns
  • The structure of TMV RNA-MP complexes depends on RNA:MP molar ratio, which is in "beads-on-a-string" and "thick string" conformations at the MP:RNA molar ratio of 20:1 and 60:1 respectively.
  • MP molecules are distributed along the polynucleotide chain of RNA
  • Interaction of RNA with MP leads to unfolding of RNA
 
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