April 30, 2024

The “Sayonara” Gene: Flies Aren’t Freaks When It Comes to Cell Death

Figure 1: Expression of the sayonara gene in the wings of a fruit fly causes the wings to shrivel due to apoptosis. Despite whats composed in books, fruit flies utilize a comparable cell-stress sensing unit as mammals to start programmed cell death.
“We utilized the hereditary sequence for a human BH3-only protein and examined whether the genome of fruit flies has a similar series– its a really common method to discover genes in fruit flies that correspond to human ones.”
The fruit flys lack of a BH3-only protein subsequently became enshrined in textbooks. The finding indicates that fruit flies, and probably other bugs, arent so different when it comes to apoptosis.

Harmed cells in our bodies eliminate themselves by initiating a suicidal process of configured cell death known as apoptosis. This procedure is essential for our health and for ensuring that cells dont become cancerous.
The molecular cascade behind this process is highly complicated, however it is activated by a single protein that belongs to a household of proteins known as BH3-only proteins. These proteins notice stress in cells and are found in many animals including mammals and nematodes.
However, for the last twenty years, fruit flies, and possibly all insects, were believed to lack BH3-only proteins. Rather, they were thought to depend on a different cell-death program.
Now, in a surprise discovery, Sa Kan Yoo of the RIKEN Center for Biosystems Dynamics Research and co-workers have actually discovered that fruit flies do certainly harbor a BH3-only protein. They called the gene that encodes for it sayonara after the Japanese word for goodbye.
Sa Kan Yoo (left) and Yuko Ikegawa. Credit: © 2023 RIKEN
When the team triggered the sayonara gene to be revealed in fruit-fly wings, they observed apoptosis taking place, resulting in withering of the wings (Fig. 1).
According to Yoo, the gene was concealed in plain sight. “We didnt do anything fancy,” he states. “We used the genetic series for a human BH3-only protein and checked whether the genome of fruit flies has a comparable sequence– its a really typical way to discover genes in fruit flies that correspond to human ones.”
Yoo presumes that insufficient sequencing of the fruit flys genome might explain why researchers didnt discover the gene in fruit flies 20 years ago. “Genomic sequencing was insufficient back then, so probably researchers could not discover the gene and after a while they simply quit.”
The fruit flys lack of a BH3-only protein consequently ended up being preserved in books. “And after just a couple of hours, I discovered something that looked suspiciously like a BH3-only protein.”
The finding suggests that fruit flies, and most likely other pests, arent so different when it pertains to apoptosis. “It indicates that fruit flies arent an exception or a bit unusual,” states Yoo. “Rather we found they have a similar system for managing apoptosis as nematodes and humans.”
The team is now exploring exactly what takes place after the BH3-only protein is activated. They are likewise investigating if other insects have BH3-only proteins.
Recommendation: “Evidence for existence of an apoptosis-inducing BH3-only protein, sayonara, in Drosophila” by Yuko Ikegawa, Christophe Combet, Mathieu Groussin, Vincent Navratil, Sabrina Safar-Remali, Takuya Shiota, Abdel Aouacheria and Sa Kan Yoo, 2 February 2023, The EMBO Journal.DOI: 10.15252/ embj.2021110454.

Figure 1: Expression of the sayonara gene in the wings of a fruit fly causes the wings to shrivel due to apoptosis. Despite whats composed in books, fruit flies use a similar cell-stress sensor as mammals to initiate set cell death.
Contrary to established understanding, RIKEN scientists have actually discovered a BH3-only protein in fruit flies that activates programmed cell death or apoptosis. This discovery recommends and challenges previous assumptions that fruit flies share a similar apoptosis mechanism with human beings and nematodes.
RIKEN geneticists have actually uncovered a protein in fruit flies that numerous textbooks say does not exist. When they are extremely stressed, the protein spots tension in cells and sets them on a pathway to self-destruction.