Last updated: 5 Oct 2015
Read the Materials & Methods sections relevant to the results you are presenting. You should understand this and be able to explain it. Nevertheless, your presentation should NOT be focussed primarily on techniques, but rather the results and discussion. Explain the methods only as much as is necessary to make the results understandable.
floxed - 'flanked by loxP sites'
A 'floxed' gene is one that has engineered 'LoxP' recombination sites on the left and right ('flanking'). When the Cre recombinase protein is expressed, the Lox sites recombine to either remove the DNA between them (Lox sites in same orientation) or invert the segment of DNA (Lox sites in opposite orientations). In the first case, this makes a deletion allele of the gene in question - but only in the cells expressing the Cre protein. (For example, this can be used to avoid a lethal phenotype in a regular homozygous deletion mutant. Or, to study the mutant phenotype in only a specific tissue.) The Cre recombinase protein can be turned on in specific cell or tissue types. In this paper, Cre recombinase protein is induced (expression turned on) in a mouse with the AhCre transgene by β-naphthoflavone injection.
A nice illustration of conditional gene inactivation by Cre-Lox system.
As described at the beginning of the results, a Cre-expressing mouse must be bred with a 'floxed' allele containing mouse first, as illustrated here.
The Wikipedia entry is also decent: floxed
See 'Conditional targeting' on this Mouse transgenics site (you may need to read more of the site to understand this section).
BrdU (BromodeoxyUridine) - a thymidine analog that is taken up and inserted into DNA like 'T' during S phase. The BrdU in cells can be detected with a specific antibody against BrdU. 'BrdU incorporation' is a measure of how many cells are proliferating (that is, in S phase). Such cells may be referred to as 'BrdU positive' cells.
Ki67 - a Ki67 antibody marks a nuclear protein found only in proliferating cells and not in quiescent (non-dividing) cells. So, it provides similar information to BrdU.
IHC - immunohistochemistry - here, using an antibody to a given protein, then an enzyme-linked secondary antibody. The enzyme substrate DAB makes a dark brown precipitate indicating presence of the protein of interest (i.e., β-catenin, c-Myc, Ki67).
Microarray analysis here involves comparing RNA expression levels from many genes in different genotypes.