Slide 1
Sequencing of the human genome was completed by 2007
DNA sequencing has depended on advances in technology, starting with making recombinant DNA
In recombinant DNA, nucleotide sequences from two different sources, often two species, are combined in vitro into the same DNA molecule
Slide 2
Methods for making recombinant DNA are central to genetic engineering, the direct manipulation of genes for practical purposes
DNA technology has revolutionized biotechnology, the manipulation of organisms or their genetic components to make useful products
An example of DNA technology is the microarray, a measurement of gene expression of thousands of different genes
Slide 3
Fig. 20-1
Slide 4
Concept 20.1: DNA cloning yields multiple copies of a gene or other DNA segment
To work directly with specific genes, scientists prepare gene-sized pieces of DNA in identical copies, a process called DNA cloning
Slide 5
Most methods for cloning pieces of DNA in the laboratory share general features, such as the use of bacteria and their plasmids
Plasmids are small circular DNA molecules that replicate separately from the bacterial chromosome
Cloned genes are useful for making copies of a particular gene and producing a protein product
Slide 6
Gene cloning involves using bacteria to make multiple copies of a gene
Foreign DNA is inserted into a plasmid, and the recombinant plasmid is inserted into a bacterial cell
Reproduction in the bacterial cell results in cloning of the plasmid including the foreign DNA
This results in the production of multiple copies of a single gene
Slide 7
Fig. 20-2
DNA of chromosome
Cell containing gene of interest
Gene inserted into plasmid
Plasmid put into bacterial cell
Recombinant DNA (plasmid)
Recombinant bacterium
Bacterial chromosome
Bacterium
Gene of interest
Host cell grown in culture to form a clone of cells containing the “cloned” gene of interest
Plasmid
Gene of Interest
Protein expressed by gene of interest
Basic research and various applications
Copies of gene
Protein harvested
Basic research on gene
Basic research on protein
Gene for pest resistance inserted into plants