Outline the two ways that piRNAs and PIWI proteins inhibit transposable elements.

IIVY is a LysR regulator, and it helps control transcription of a neighboring gene, ilvC. IlvY can either bend the DNA and block RNAP's access to ilvC's -35 promoter site, or it can allow access to the ilvC -35 site, thereby promoting ilvC transcription. What determines whether llvY is repressing or activating transcription from the ilvC promoter? The presence of the co-inducer acetolactate - acetolactate binds to llvY and changes llvY's shape such that it doesn't block the -35 of the ilvC promoter. IlvY represses ilvC transcription when the IlvC protein is bound to llvY, and it activates ilvC transcription when the lvC protein is not present to bind to llvY. The presence of the co-inducer valine - when valine is present, it binds llvY and causes llvY to repress transcription from the ilvC promoter. The presence of the co-inducer acetolactate - acetolactate induces negative supercoiling at the ilvC promoter, which represses ilvC transcription.

Describe two ways that piRNA can suppress the activity of transposable elements.

What are the    types of transposable elements in eukaryotic cells?