Sexual maturity is an organism’s capacity for reproduction. It is often referred to as adulthood or puberty. In humans, the biological term is puberty, while adulthood is defined by cultural norms. This article will discuss the different types of sexual maturation and explore the effects of JH and 4-VA treatments.
Mechanisms underlying pheromone-mediated sexual maturation
Pheromones are small chemical molecules that regulate sexual behavior in rodents. These compounds are produced by the female house mouse and are believed to control her reproduction and communicate her reproductive status to males. These molecules also inhibit reproduction and regulate mating behavior.
The effects of pheromones on reproduction are well documented in a number of species. For example, exposure to the odor of a nearby adult female has been found to delay the onset of puberty in female mice. It also suppresses the estrus cycle in adult female mice. Exposure to the odor of an unfamiliar adult male also induces a high rate of pregnancy failure in females. Nevertheless, studies are still in progress.
The action of male pheromones on prepubertal females and adult females is similar. In sub-social species, hydrocarbons are important for fertilization. But pheromones do not trigger puberty, but they do accelerate the process of sexual maturation. This mechanism is also reflected in the synchronization of oocyte maturation and oviposition in gregarious females.
Effects of conspecific interactions on female sexual maturation
Studies have shown that female flies are more likely to become sexually mature in the presence of males than in the absence. This may be due to the pheromones released by males, which may have been a cue for the females to become sexually mature. In the same way, chemical signals released by males have been shown to influence the onset of puberty in male house mice.
It has also been shown that males in N. senegalensis can fertilize multiple females, and this may result in a flexible mating strategy for males. Although individual males may visit as many as four females, it is not known how much these males can affect the female’s sexual maturation. However, behavioral mating experiments suggest that males may use the differential mating investment to improve their chances of finding a virgin female.
Females that had previously been courted by heterospecific males were tested for consent to conspecific mating. Whether females consented to interspecific mating was noted as well as the length of the previous courtship between the male and female. Females who had previously interbred with heterospecific males tended to have higher receptivity than those who had mated with the heterospecific male once. However, the results suggest that females from both species may be similarly affected by heterospecific mating costs.
Effects of 4-VA treatment on female sexual maturation
In this study, a compound targeting CA, 4-VA, decreased the amount of JH in females and reduced their ability to mate. These results suggest that JH may be involved in female sexual maturation. Although research is limited at this time, 4-VA treatment is promising.
Effects of JH on female sexual maturation
The effects of JH on female sexual maturation have not been fully understood, but it is suspected that the hormone regulates specific CHCs, including the C27 and C29 dienes. This hormone regulates the synthesis of key female sex pheromones, which are essential for early female sexual maturation. The primary receptor for JH is the Met. In females, the presence of this hormone causes the onset of mating.
In females, the expression of vitellogenin (Vg) is regulated by the hormone JH. Females exposed to 4-VA significantly increased their hemolymph JH titer. The expression of vitellogenin was also increased in both the fat body and the ovary of these females. In contrast, females that were not exposed to 4-VA showed no significant increase in JH titers.
The role of JH in female sexual maturation has been studied in insects. In the female Drosophila melanogaster, JH is necessary for egg maturation, but its removal delays mating and the production of female sex pheromones. Met JH acts through a Methoprene-tolerant JH receptor, which is similar to the Germ-cell JH receptor. This finding provides insights into the molecular mechanisms that regulate reproductive behavior, and may have application to other complex behaviors in animals.