Figure 7-6. Fragments produced by cleavage of the ≈36-kb DNA genome from adenovirus 2 (Ad2) by EcoRI and another restriction enzyme, HindIII from Haemophilus influenzae.

Figure 7-6Fragments produced by cleavage of the ≈36-kb DNA genome from adenovirus 2 (Ad2) by EcoRI and another restriction enzyme, HindIII from Haemophilus influenzae.

Double-stranded DNA is represented by single black lines in this figure. Digestion of Ad2 DNA (center) with EcoRI generates 6 EcoRI fragments (top); these result from cleavage at each EcoRI restriction site (GAATTC) in the Ad2 sequence. Digestion with HindIII cleaves the Ad2 DNA at each HindIII site (AAGCTT), generating 11 specific fragments (bottom), all different from the EcoRI fragments. By convention, restriction fragments are labeled A – Z in order of decreasing size. By techniques described later, the order of fragments in the original DNA can be determined, thus mapping the restriction sites on the uncut DNA (indicated by short arrows). Such a “restriction-site map” for various restriction enzymes is a unique characteristic of each DNA.

From: Section 7.1, DNA Cloning with Plasmid Vectors

Cover of Molecular Cell Biology
Molecular Cell Biology. 4th edition.
Lodish H, Berk A, Zipursky SL, et al.
New York: W. H. Freeman; 2000.
Copyright © 2000, W. H. Freeman and Company.

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