Protocol describes a method for electroporating DNA into ES cells, as well as selection methods. Pilot studies should be performed to optimize the conditions for each DNA construct. The selection method described here is one of the most complex. It involves targeting constructs in which the bacterial neomycin-resistance gene disrupts the coding sequence of the mouse gene. - [Read Electroporating DNA into Embryonic Stem (ES) Cells and Selection Methods Protocol]
Mice fed with the cytohesin inhibitor SecinH3 for two days develop hepatic insulin resistance that can be identified by reduced liver glycogen levels, increased serum insulin and ketone body levels and decreased serum non-esterified fatty acid. To confirm the presence and identity of SecinH3 in mouse liver, we extracted the compound from liver homogenates with chloroform and identified it by LC/MS. - [Read Extraction of the SecinH3 from Mouse Liver Protocol]
Forward genetics is used to identify genes that are involved in particular biological processes. For example, genes required for disease resistance can be found by identifying mutants with reduced or increased disease resistance, genes that control flower development can be identified by searching for mutants with altered flower morphology, and genes encoding enzymes for tryptophan biosynthesis can be identified by searching for mutants that require exogenous tryptophan for growth. - [Read Forward Genetics in Arabidopsis: Finding Mutations that Cause Particular Phenotypes Protocol]
The most commonly used markers for selection of transgenic Arabidopsis are resistance to the antibiotic kanamycin and to the herbicide glufosinate ammonium. Resistance to kanamycin is conferred by a bacterial gene encoding the enzyme neomycin phosphotransferase (NPT). In this protocol, kanamycin-resistant seedlings are selected on solid medium. - [Read Kanamycin Selection of Transformed Arabidopsis Protocol]
This stage of the procedure describes the transfection with target genes of cell lines already expressing inducible tTA. In this example, the target genes are transfected on a plasmid that carries puromycin resistance as a selectable marker. - [Read Tetracycline as Regulator of Inducible Gene Expression Protocol II]