Objective and Definition
- The genetics laboratory, course number BIOL3452.502, is to conduct a forward genetic screen on the N2 strain of roundworm Caenorhabditis elegans.
- A forward genetic screen involves the observation of a phenotype of interest within a mutagenized germline.
- Through the careful execution of a forward genetic screen on C. elegans, we will acquire a better understanding of the “relationship between gene, allele, wild-type and phenotype.” (padilla 2012)
- Group 2 has chosen to study movement related traits by isolating mutants known as rollers.
- Our hypothesis is that, by isolating roller mutants of C. elegans, we attain a deeper understanding of the genetic mechanisms influencing nematode movement.
- A population of N2 C. elegans, the P0 generation, will be acquired and mutagenized by Ethyl Methanesulfate (EMS). Individual worms from this generation will produce spatially separated F1 offspring. A select few F1 individuals will reproduce further and produce an F2 progeny.
- The F2 generation of this test group will then be screened for the roller mutation. The progeny of these rollers, the F3 generation, will yield the most integral data of our screen.
- Observing the phenotype of all resulting F3 progeny will elucidate how the roller mutation is passed from parent to offspring, i.e. its relationship to the other rol-9 alleles.
- The ways in which the roller mutation effects movement may be the result of rol-9’s role (no pun intended) in a greater genetic/chemical system dictating motility in Caenorhabditis elegans.
- Through further screens and analysis, the “molecular characteristic of the mutant allele…can be mapped and sequenced.” (padilla 2012) Executing PCR analysis coupled with Gel Electrophoresis on the mutant and wild type forms of the rol-9 gene will allow us to understand the nature of the aberrant code within the roller mutants.
- There are 14 classified rol-9 mutations that cause the roller phenotype. Our forward genetic screen is preformed with the intent of locating and characterizing novel rol-9 mutations.
- Once that data has been tabulated, the mutant and wild type gene products (RNA and Proteins) may be compared, lending insight into the requirements of functional motility in Caenorhabditis elegans.
- A BLAST (Basic Local Alignment Search Tool) search will also reveal connections between regulated motility in C. elegans and humans.