It has been a bug-like, sexual head-scratcher for years.of Japanese blue earthworm Megacilis nipponica Separate the butt to reproduce. But how do algae-eating invertebrates do this? According to one researcher, the process may be due to several developmental genes. The study was published Nov. 22 in the journal scientific report.
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Bye bye, ass
Some segmented sea worms, such as silid worms, undergo a reproductive process called. Creeping. The stolon is the posterior organ of the nematode and is filled with eggs or sperm, depending on the sex of the worm. During stolon formation, the stolon is completely separated from the rest of the nematode’s body for reproduction.
This detached butt swims around on its own and lays eggs when it encounters a stolon of another sex. This autonomous swimming protect the worm’s original body It protects against environmental hazards and allows eggs and sperm to travel longer distances.
To swim independently, creeping birds must develop their own eyes, antennae, and swimming hairs while remaining attached to their original body. How this could happen was a mystery.The formation of the stolon itself It begins when the gonads near the insect’s butt mature.. A head then forms at the front of the developing stolon, followed closely behind by eyes, antennae, and swimming hairs. Before the stolon separates from the rest of the body, nerves develop and the ability to sense and act independently develops.
hot hox gene
new study, a team from the University of Tokyo investigated how the stolon head forms in the first place. The researchers investigated developmental gene expression patterns as the worms reach sexual maturity.A well-known group of genes that determine the formation of body parts called hox gene Helps define the head areas of different animals. The research team found that the hox gene was more expressed in the head region of the stolon. Genes are usually less expressed in the midsection of the body, except when the gonads are developing. During this period, hox genes are highly expressed in the midsection and rump of the worm.
“This shows how normal developmental processes are modified to suit the life history of animals with unique reproductive styles,” said study co-author Toru Miura, a marine biologist at the University of Tokyo. he said. stated in a statement.
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Hox genes also determine division along the worm’s body. The researchers suspected that hox genes would be differentially expressed along an invisible line that runs from the head to the rear end of the worm.
“Interestingly, the expression of Hox genes, which determine the identity of body parts, remained constant throughout the process,” Miura said.
Because of this consistency, stolons do not have a separate digestive tract. It also has repeated homogeneous body segments, except for the head and tail.
“This indicates that only the head is guided in the hind body to control spawning behavior for reproduction,” Professor Miura said.
This study revealed for the first time the mechanism of stolon development and prompted further research into this reproductive method. In future studies, Miura and his research team hope to elucidate the sex-determining mechanism and endocrine regulation of the nematode’s reproductive cycle.