GMOs & Animal Clones

Class 23

Transgenic organism

genome contains a gene from the same or different species

Pronuclei

time period of fertilization when the two haploid nuclei have not yet fused together

P element

• only in drosophila

• class of DNA transposon that contain the gene for the transposase protein

  • transposon ends are inverted repeats

  • protein binds inverted repeats, cuts the transposon out of genome, and pastes it into a new location

P element vectors

• plasmids that contain P element ends without the transposase gene

• transposase gene is replaced with a marker gene for detection of transgenic flies

P element transformation

process utilizing P elements as vectors to transfer genes into germ-line cells

Ti plasmid vector

• vector from “tumor-inducing” plasmid of a bacterium

• good for putting transgenes in plants

T-DNA

• transferred DNA

• segment of Ti plasmid DNA present in bacteria that infect plants

• integrates into plant genome, causing overgrowth, forming a tumor

Transgenes (uses)

• can figure out which genes’s absence cause a certain phenotype

• can analyze gene expression via reportor transgene

• can create protein drugs in eukaryotic cells

Reporter transgene

foreign genes whose produces are easy to detect

Reproductive cloning

• using somatic cell nuclei of transgenic adults to generate other animals with identical genomes

• a way to enhance the value of a rare, high-producing animal

• better than using transgenic animals from pronuclear injection

  • otherwise would have variable numbers of transgene copies, which would be present a random genomic locations

Somatic cell nuclear transfer

• process used to create reproductive clones

• taking the diploid nucleus of a somatic cell, inserting it into an egg with its original nucleus removed, and planting it into a surrogate mother

  • three mothers, no sperm needed: one provides the nucleus, one provides oocyte, one provides the womb

  • whoever provided the nucleus is who is cloned