The queen ant mates with a male shortly after emergence, and continues to store the sperm received at that time in the "fertilization sac" in the body until it dies, and repeats spawning.Queen ants are known to have an extremely long lifespan compared to other insects, with many species reaching more than 10 years.Considering that male sperm of general animals deteriorate significantly within hours to days after mating and fertilization ability declines, the ability of queen ants to store sperm at room temperature for as long as 10 years or more is extremely special. As can be said, the molecular mechanism has not been understood at all so far.
Collaborative research groups such as Konan University, University of Tsukuba, Kagawa University, and Ryukyu University have comprehensively investigated what genes are actively working in the fertilized sac of Queen Ali to elucidate this mechanism.As a result, we found an antioxidant enzyme gene that was expected to be involved in sperm storage, and a gene whose specific function is unknown but whose expression level is extremely high.Most of these were expressed not only in the fertilization sac but also in active organs such as the ovary and midgut, while 12 genes strongly expressed only in the fertilization sac were found.Since the functions of these 12 genes are completely unknown in the reproductive organs of other organisms, it is possible that they are genes with specialized functions for sperm storage in queen ants.
In the future, we aim to clarify how these fertilization sac-specific genes affect sperm survival and physiological status, and to elucidate the whole picture of the long-term sperm storage mechanism of queen ants.In the future, it is expected to lead to the development of low-energy and high-quality storage technology for sperm in the field of livestock and infertility treatment.
Paper information:[Scientific Reports] Transcriptome profiling of the spermatheca identifies genes potentially involved in the long-term sperm storage of ant queens
