Behavioral Genetics and Animal Science TEMPLE GRANDIN AND MARK J. A bright orange genetic modification research paper is setting on a prehistoric horizon. A lone hunter is on his way home from a bad day at hunting. As he crosses the last ridge before home.
Investigating, he discovers some wolf pups hiding in a shallow den. After a quick scan of the area for adult wolves, he cautiously approaches. Synthetic Biology aims to engineer artificial pathways in cells both to test fundamental notions of how complex biological networks function and to develop new technologies for the treatment of disease. Congratulations to Nili, Miguel, and Sonja on their paper in Science Advances! Congratulations to Nina on beginning her PhD at the University of Washington!
Congratulations to Joe on receiving an NSF graduate research fellowship! Jimenez on defending his thesis and beginning a postdoc in Steve Langer’s lab at MIT Koch Institute! Congratulations to Andrew and Zhixing on their paper in Chemical Communications! Ng on defending his thesis and beginning as a data scientist at Genetic Intelligence!
Sanguineti on defending her thesis and beginning as an assistant program director at Brooklyn College! Patenode on defending her thesis and beginning as a program manager at Womensphere Foundation! Congratulations to Sean on receiving an NSF graduate research fellowship! Congratulations to Andrew and Annie on their paper in Nature Methods! Additional information that is not directly included in AS Biology. However it can help to consolidate other techniques. This makes use of the enzyme reverse transcriptase, which does the reverse of transcription: it synthesises DNA from an RNA template.
It makes genes much easier to find. However a given cell only expresses a few genes, so only makes a few different kinds of mRNA molecule. For example the b cells of the pancreas make insulin, so make lots of mRNA molecules coding for insulin. They are properly called restriction endonucleases because they cut the bonds in the middle of the polynucleotide chain.
DNA by complementary base pairing, but only if they have both been cut with the same restriction enzyme. 4-8 base pairs long, called recognition sequences. Short lengths of DNA cut out by restriction enzymes are called restriction fragments. The sticky ends allow two complementary restriction fragments to anneal, but only by weak hydrogen bonds, which can quite easily be broken, say by gentle heating. DNA ligase completes the DNA backbone by forming covalent bonds. Restriction enzymes and DNA ligase can therefore be used together to join lengths of DNA from different sources. For example the mosquito is a disease vector because it carries the malaria parasite into humans.
It contain marker genes, so that cells containing the vector can be identified. Many different vectors have been made for different purposes in genetic engineering by modifying naturally-occurring DNA molecules, and these are now available off the shelf. Plasmids are short circular bits of DNA found naturally in bacterial cells. The diagram below shows how DNA fragments can be incorporated into a plasmid using restriction and ligase enzymes. Several other products are also formed: some plasmids will simply re-anneal with themselves to re-form the original plasmid, and some DNA fragments will join together to form chains or circles. This heat shock causes some of the cells to take up the vector, though no one knows why.