|Bacillus thuringiensis spore and protein crystals|
Protein crystals made by strains of Bacillus thuringiensis are toxic to certain insects and have been put to use as a biopesticide.
|Biochemical pathway for beta-carotene production in golden rice|
The biochemical pathway for beta-carotene synthesis in "golden rice."
|Cloning animals by nuclear transfer|
A donor cell is fused with enucleated egg cell by subjecting the two cells to pulses of electricity. The cell replicates in culture, generating an embryo, which is then introduced into the uterus of a female for development.
|Gene disruption by homologous recombination|
The plasmid contains a gene interrupted by a marker gene (XR). Recombination involving two crossovers between the plasmid and wild type chromosomal DNA with the interrupted gene and the selectable marker.
A "gene gun"
|Selective breeding of maize|
The ancestor of modern corn had tiny kernels, each protected by a tough husk. Domestication of maize, which began thousands of years ago, selected for large sheathed cobs containing large kernels without husks.
1) DNA fragments are generated using restriction enzymes. 2) The fragments are separated in a gel by the application of an electric charge. 3) The fragments are then blotted onto a piece of nitrocellulose paper, where they retain their same pattern of separation, but are denatured to become single-stranded DNA. 4) A unique single-stranded portion of the gene of interest (the probe) is radioactively labeled and allowed to anneal with the blotted paper. 5) When exposed to a sheet of photographic film, any DNA fragments that annealed with the labeled probe are identified.
|Sporulating Bacillus thuringiensis cell|
Protein crystals made by strains of Bacillus thuringiensis are toxic to certain insects and have been put into use as a biopesticide.