LIFESCI 3 Chapter Notes - Chapter 7.1: Restriction Enzyme, Dna Ligase, Recognition Sequence
Document Summary
Dna cloning: separate a specific gene or dna segment from a larger chromosome attach it to a small molecule of carrier dna introduce to host cell replicate the dna. Restriction endonucleases recognize specific sequences and cleave genomic. Genomic dna can also be sheared randomly into fragments of a desired size. Some dna segments that are known can simply be synthesized. Select a small molecule of dna capable of self-replication. Cloning vectors: modified versions of naturally occurring small dna molecules. Dna ligase links cloning vector to dna fragment creating recombinant dna. Move recombinant dna from test tube to host organism. Host provides enzymatic machinery for dna replication. Select or identify host cells that contain recombinant dna. Cells containing the vector are selectable in certain environments where cells lacking the vector would usually die. Genes are cloned by insertion into cloning vectors. Restriction endonucleases recognize dna at specific recognition sequences and cleave it to generate smaller fragments.
