What are RNAi pathways?

RNA interference (RNAi) is a form of post-transcriptional gene regulation in which non-translated double-stranded RNA (dsRNA) molecules called small interfering RNA (siRNA) mediate sequence specific degradation of target messenger RNA (mRNA).

What did the chef represent in the NOVA video on RNAi?

In the first analogy, a chef makes bread from a recipe copied from a master recipe. In the second analogy, a second, double-message version of the bread recipe is introduced. This difference is enough to trigger an RNAi response, which keeps both recipes from getting to the chef.

What is the main purpose of the RNAi pathway?

RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is a conserved biological response to double-stranded RNA that mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.

What role did the petunia play in the discovery of RNAi?

Background. In 1998, scientists discovered that petunias, nematodes, fruit flies, mice, and even humans use a built-in cellular mechanism to protect their genome (set of genes) from attacks by viruses.

How do Mirnas function in controlling gene expression?

microRNA controls gene expression mainly by binding with messenger RNA (mRNA) in the cell cytoplasm. Instead of being translated quickly into a protein, the marked mRNA will be either destroyed and its components recycled, or it will be preserved and translated later.

What does RNAi do when we add genes to create more purple petunias Why?

The genes the geneticist added to make more purple pigment in the petunia caused the plant to respond as though it had been infected with a virus, triggering an RNAi response. As a result, the plant stopped making pigment, which resulted in the production of only unpigmented (i.e., white) flowers.