368 < mm- i ik 28 



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 W. M.. "The Complete Amino Acid Sequence of the Protein of Tobacco Mosaic 

 Virus," Proc. Nat. Acad. Sci., U.S., 46:1463-1469, I960. 



Weissmann, c .. Borst, P., Burdon, R. H.. Billeter, \1. A., and Ochoa, S.. "Replication 

 oi Viral RNA, IV. Properties of RNA Synthetase and Enzymatic Synthesis ol 

 MS2 Phage RNA." Proc. Nat. Acad. Sci.. U.S.. 51:890-897, 1964. 



QUESTIONS FOR DISCUSSION 



28.1. What conclusions can you draw from the observation that within a day or so 

 alter infection with a single particle of TMV, the cell can produce about 50,000 

 viral nucleic acid molecules and about 100 > 10 6 protein subunits? 



28.2. Using pure TMV RNA for infection, how could you test whether this RNA 

 contains information for manufacturing TMV protein? 



28.3. Compare transformation with infection by pure virus nucleic acid. 



28.4. Discuss the view that cancerous growths may originate as a result of virus in- 

 fection activating RNA replication. 



28.5. What conclusions can you draw from the observation (see reference to J. E. 

 Davis and R. L. Sinsheimer) that the RNA of the parental MS2 phage is rou- 

 tinely excluded from the progeny phage? 



28.(i. What are the similarities and differences in the behavior of DNA polymerase 

 and RNA synthetase? 



28.7. Discuss the possible advantages and disadvantages of double-stranded rather than 

 single-stranded RNA as the genetic material of a mature virus. 



