Becker's World of the Cell 9th Edition by Lewis Kleinsmith, Jeff Hardin, Gregory Paul Bertoni

Exercise 9

TMV Assembly. Each of these statements is an experimental observation concerning the reassembly of tobacco mosaic virus (TMV)virions from TMV RNA and coat protein subunits. In each case, carefully state a reasonable conclusion that can be drawn from the experimental finding.
(a)When RNA from a specific strain of TMV is mixed with coat protein from the same strain, infectious virions are formed.
(b)When RNA from strain A of TMV is mixed with coat protein from strain B, the reassembled virions are infectious, giving rise to strain A virus particles in the infected tobacco cells.
(c)Isolated coat protein monomers can polymerize into a viruslike helix in the absence of RNA.
(d)In infected plant cells, the TMV virions that form contain only TMV RNA and never any of the various kinds of cellular RNAs present in the host cell.
(e)Regardless of the ratio of RNA to coat protein in the starting mixture, the reassembled virions always contain RNA and coat protein in the ratio of three nucleotides of RNA per coat protein monomer.