Content advisory
This digitised material is free to access, but contains information or visuals that may:
- include personal details of living individuals
- be upsetting or distressing
- be explicit or graphic
- include objects and images of objects decontextualised in a way that is offensive to the originating culture.
Licence: In copyright
Credit: Spetsai, Greece. Source: Wellcome Collection.
5/12
![J. CAIBNS »NA rvnth.^ir? Ir. bnotcria The mechanism of DNA synthesis is being worked out (1) by studying the structure of replicating DNA in the electron microscope (2) by developing systems that replicate DNA in vi tro in which the various macromolecular components of replication can be tested (3) by collecting mutants that ore defective in DNA synthesis and then finding out the exact nature of their defect and (4) by looking at the properties of the intermediate products of DNA synthesis in vivo . All these methods are somewhat interrelated. Reference ^: M, Goulian. Biosynthesis of DNA. Ann. Rev. Biochem. 40 . 855-898, 1971. D.R. Helinski, D.E. Clewell. Ann. Rev. Biochem. 40, 899-9^2, 1971. R.B. Inman, M, Schnos. J. Mol. Biol. ¿6, 319, 1971. D.W. Smith, H. Schaller, F. Bcnhoeffer. Nature 226 , 711, Î97O. J- ROBERTS Lecture 1 . P?cte-ial Tr^ircripjlnn The expression of genetic information proceeds through the synthesis of a messenger RNA molecule which is a copy of the gene nucleotide sequence, and which serves as a template for synthesis of the polypeptide gene product. Our understanding of the details of this process in E. coli will be discussed. Reference; Chamberlin, M.J. Summary article in Cold Spring Harbor Symposium on Quanti tative Biology, I97O. Lecture 2. Bacteriophage L^bda The temperate bacteriophage lambda provides a system for study of trans criptional controls which is both well characterized genetically and premis ing for biochemical analysis.• An introduction to the study of lambda will be given. Reference ; Herskowitz and Signer in Cold Spring Harbor Symposium on Quantitative Biology, I97O. and The Bacteriophage Lambda, edited by Hershey and published by Cold Spring Harbor, I97I. M. GB. UNBDR G -MANA C C Lee tu.re 1. Rpy-y — Tv^.-crirt-i:-c The RNA tumor viruses contain an enzyme capable of transcribing the 60 to 703 viral RNA into DNA. An important biological role for the viral RNA- dependent DNA polymerase has been suggested by evidence indicating the 2xis tene« of a DNA intermedial il vira] •> j 3 i cation. This led to the pro- virus hypothesis ; multiplication of RNA oncogenic viruses would imply a DNA intermediate, and it wouli be as DNA (provirus) that th< viral genetic i for mation could be integrated into the host cell. : role of th< se polymer ses in the ri plie tion of oncogenic viruses](https://iiif.wellcomecollection.org/image/b18180747_PP_CRI_E_1_20_8_0005.jp2/full/800%2C/0/default.jpg)
