https://phys.org/news/2018-11-invading-genes-thwarted.html

"Because temperature had been widely known to affect sterility, we decided to quantify the rates of this jumping gene's activity at different temperatures. We discovered that the rate of jumping gene mobilization was seven times greater at 77 degrees F in ovarian stem cells, which means we can simply use temperature to control the invasion intensity from jumping genes," remarked Sungjin Moon, the first author of the paper.

The junior research group, led by Staff Associate, Zhao Zhang included Carnegie's Sungjin Moon, Madeline Cassani, Yu An Lin, Lu Wang, and Kun Dou. With this knowledge the team established the fly adult ovary as a powerful platform to uncover the underlying adaptation mechanism. They found that reproductive stem cells use a novel adaptive response to "rapidly tame" the invading elements by activating the so-called DNA damage checkpoint. This is a process that activates a pause in the cell cycle, before cell division, to repair damaged DNA. A checkpoint component, called Chk2, was found to be key. This pause in the repair process amplified the production of piRNA—those non-coding RNA elements that silence the jumping genes. They found that this pause period is necessary for adaptation and for permanently silencing the invading jumping genes, which allowed for normal egg production that could begin within four days.