How far would you be willing to push yourself to increase your life span of 500% ? A species of ant engages in brutal fights across the colony to replace the recently deceased queens, and the victor not only wins the throne but also gains a dramatic increase in her longevity.
When a queen dies, Indian jumping ants (Arpegnathos jumper) fight over which worker will take his place. To win the crown it is not enough to lay eggs, you also have to live 500% longer than the average worker. Now scientists may have discovered how surrogate queens slow their aging.
The secret lies in a protein called Imp-L2, which counteracts some of the effects of insulin in the surrogate queen ant’s body, according to a new study published Thursday (Sept. 1) in the journal Science.
In general, the hormone insulin helps direct sugar from the circulatory system to the cells, where it can be used as fuel. Surrogate queens – officially called pseudo-queens or gamergates, referring to the Greek words for “married worker” and not the misogynist GamerGate online harassment campaign – must increase their insulin production to cope with the staggering amount of food they need. to eat.
“If you want to lay eggs, you have to have a lot of insulin because you are constantly eating,” Claude Desplan, a professor of biology and neural sciences at New York University, co-lead author, told Live Science.
While necessary, this influx of insulin should theoretically pose a problem: in addition to helping transport sugar into cells, insulin triggers several molecular chain reactions, some of which contribute to the aging process. Specifically, the “Akt signaling pathway” – which mediates many cellular functions, from metabolism to cell survival – can be activated by insulin and has long been linked to aging and age-related diseases.
So if a pseudo-queen starts producing huge amounts of insulin, she should theoretically age faster than the average worker ant, which doesn’t produce as much of this hormone. “But in the case of these ants, it’s the exact opposite,” Desplan said. The average lifespan of a typical worker ant is nearly eight months, while pseudoregins can live about three years and three months. “This is a huge lifespan extension,” he said.
Interestingly, if a pseudoregina is placed in another colony with an already established ruler, she will go back to being a normal worker, Desplan said. These ancient pseudo-queens are called “revertants” and have a lifespan similar to workers. Somehow only queens and pseudo-queens, despite all their insulin, manage to survive for years.
To resolve this apparent paradox, Desplan teamed up with his longtime collaborator, Danny Reinberg, a professor of biochemistry and molecular pharmacology at New York University’s Grossman School of Medicine.
Their team took tissue samples from workers, regressives and pseudo-employees of H. jumper, focusing on the tissues involved in metabolism and reproduction. These included the brain, ovaries, adipose tissue, an organ similar to the human liver, and adipose (fat). Using a technique called mass RNA sequencing, the team analyzed which proteins were being built in the sampled tissues. A molecular cousin of DNA, RNA carries genetic instructions on how to build proteins, passing those blueprints from the cell’s command center to one of the cell’s protein building sites.
Taking a look at these instructions for RNA (yes, like that good old vaccine), the team found that, compared to female workers and revertants, pseudo-queens produced significantly more insulin in the brain and started producing more fat. and vitellogenin, a precursor to egg yolk – in the fat body. Some of these resources from the fat body have been transported to the ovaries, to support egg production, and some of the fat has been used to create a unique pheromone that only exudes queens and pseudoregins. (It is the disappearance of this pheromone in a nest that prompts worker ants to fight a duel after the death of their queen.)
When pseudo-queens produce insulin, their ovaries grow and develop so they can carry eggs. Insulin directs this process of ovarian maturation through the “MAPK signaling pathway”, another chain of chemical reactions that can be triggered by insulin. At the same time, the team found that the ovaries produce Imp-L2, which essentially blocks the Akt signaling pathway, which could otherwise cause rapid aging in pseudo-queens.
The team determined that the Imp-L2 secreted by the ovaries also travels in the fat body and acts as an anti-aging shield for this organ as well.
“The two main branches of the insulin signaling pathway, MAPK and Akt, appear to differentially regulate fertility and lifespan, with an increase in signaling in one promoting reproduction in pseudoregins and a decrease in signaling in pseudoregins. other than that it is consistent with their increased longevity, “Reinberg said in a statement.
The next step for the team will be figuring out how Imp-L2 only blocks the pathway related to aging and not the one related to reproduction, Desplan told Live Science. The team plans to study the effects of the insulin-blocking protein in other insects, including fruit flies, and thus possibly in mammals.
“We don’t know exactly what’s going to happen,” Desplan said. “Flies and ants aren’t exactly alike.” And it’s even more difficult to predict whether the anti-aging benefits that Imp-L2 brings to Indian jumping ants will apply to non-insects, such as mammals, he added.