This website was constructed as a class project for Genetics 564, an undergraduate Genetics course at UW-Madison.
What is RNAi?
RNA-interference (RNAi) is a method of repressing gene expression in vivo. As shown in the diagram below, dsRNA (double-stranded RNA) is synthesized, then broken down into smaller siRNA (small interfering RNA) segments that bind to the mRNA of interest in what is called the RISC complex. The RISC complex is responsible for degrading the mRNA from the gene of interest, which prevents it from being translated into a protein. This method is useful for studying genes and proteins, and how the cell would function when they are "knocked out" or absent because translation is prevented.
RNAi and aldolase B
In 2012, Miller et al. demonstrated that RNAi could be used to induce temperature-sensitive paralysis, shortened lifespan, and neurodegeneration in Drosophila [1]. They knocked out the aldolase gene to determine its importance in neurological function. Instead of one gene for each isozyme (α, β, and γ), Drosophila have one gene that encodes all three isozymes. Since this group used RNAi to degrade mRNA from the aldolase gene as a whole, it prevented all three isozymes from functioning. Aldolase C is expressed in the brain, so these phenotypes are most likely the result of aldolase C, rather than aldolase B, deficiency [2]. It would be interesting, however, to determine if any of these symptoms are also results of just aldolase B deficiency. Using RNAi to look specifically at deficiency of one aldolase isozyme is difficult, but this experiment has inspired me to use a different technique to examine 1) whether any of the symptoms seen by Miller et al. could be associated with aldolase B deficiency, and 2) whether knocking out just aldolase B using a different technique could be used in a genetic screen to research the possibility of an HFI dietary supplement. More information about this can be found in my Specific Aims.
References
1. Miller, D, Hannon, C, and Ganetzky. (2013). A mutation in Drosophila aldolase causes temperature-sensitive paralysis, shortened lifespan, and neurodegeneration. Journal of Neurogenetics. 26 (3-4): 317-327. doi: 10.3109/01677063.2012.706346.
2. NCBI. (2014). ALDOC aldolase C, fructose-bisphosphate. Retrieved May 18, 2014 from http://www.ncbi.nlm.nih.gov/gene/230.
2. NCBI. (2014). ALDOC aldolase C, fructose-bisphosphate. Retrieved May 18, 2014 from http://www.ncbi.nlm.nih.gov/gene/230.