Molecular cloning of recombinant DNA : proceedings of the Miami winter symposia, January 1977 / edited by W.A. Scott, R. Werner ; sponsored by the Department of Biochemistry, University of Miami, School of Medicine, Miami, Florida.

Date:: 1977

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Molecular cloning of recombinant DNA : proceedings of the Miami winter symposia, January 1977 / edited by W.A. Scott, R. Werner ; sponsored by the Department of Biochemistry, University of Miami, School of Medicine, Miami, Florida. Source: Wellcome Collection.

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$12 paul berg Restriction endonucleases have played a crucial part in defining the genetic and functional organization of the SV40 genome (25). The restriction or cleavage sites serve as coordinates for a molecular map of the DNA and permit one to locate, accurately, particular physical features or genetic loci. The single EcoRI endonuclease cleavage site serves as the reference marker and is assigned map position 0/1.0; all other positions in the DNA are given map coordinates in SV40 DNA fractional lengths measured clockwise from 0/1.0 (Fig. 5). Geography of SV40 Chromosome Proteins vpi (45k) vp2(35k) vp3(25k) Complementation Groups [b,c.bc],d,e a(70-95k) tsta (?) и (?) Figure 5. The early proteins (A, TSTA and U antigen) are expressed from the early region, while the capsid pro¬ teins, VPI, VP2, and VP3 are coded for by the late region. The SV40 chromosome, after it enters the nucleus of in¬ fected primate cells, is expressed in a regulated temporal sequence. Initially, a viral RNA transcript, complementary to one strand (the E-strand) of about one half of the DNA, appears in cytoplasmic polysomes. This transcript, synthe-$