Describe the function of the oriC. What do you predict will happen to the cell if 100 bp between the 13-mer and 9-mer sequence is deleted as indicated in the figure?
What will be an ideal response?
A consensus sequence is the portion of a conserved region that carries out the essential function that is the focus of natural selection. The 13-mer and 9-mer consensus sequences that are part of oriC have been maintained by natural selection because they have essential functional roles in replication initiation, as we explain in the following section. Beyond the presence of the consensus sequences themselves, natural selection also acts to maintain specific spacing between the consensus sequences. Spacing is important because DNA-binding proteins must assemble at sites where consensus sequences are located. Different proteins are attracted to different consensus sequences, and each protein must have the physical space to bind to DNA and to interact with the other proteins bound to the consensus sequence region. The spacing between consensus sequence elements is also important to allow room on the DNA molecule for protein binding and interaction between bound proteins. If you delete this region, replication will not proceed because there is not enough space for replisome assembly.
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because of
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A) European B) Asian C) African D) Australian E) North American
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