Dear all,
as a beginner in work with C. elegans and the lab in general, I have a question that is probably profane for you, but important for me to plan my experiments.
I want to test different mutants for their gene expression upon treatment with substances. I was wondering whether it is possible to induce the expression of a knockdown gene.
Then I stumbled across different descriptions for different mutant strains. Some are knockout mutants, others have a deletion, others are deficient. What is the difference here and can these genes still be up- or down-regulated in a PCR analysis when treated and untreated worms are compared?
I would appreciate your feedback!
LabNewbie,
Mutants that are labelled “knockout” or “deletion” are missing part of the coding sequence for the gene. So there is no way to increase functional protein levels - the coding sequence for the protein is absent. Mutations that are “partial loss of function” may have mutations in the coding sequence that cause the protein to have lower activity (most common) or may have differences in the non-coding regions that decrease expression (less common). Of course, if you are looking at RT-PCR, you will be looking at mRNA levels and not protein expression. If you are interested in whether chemicals cause acute increases in mRNA levels for a set of genes, then you may just want to examine normal worms. I recommend that you go to the wormbook.org and read some of the basic sections on genetics to become more familiar with worm genetics.
Janet