The determination of a number of pheromone structures from species of Euplotes provided direct evidence that these cell typespecific signals are represented by families of homologous proteins, consistently with their genetic control through series of single-locus multiple alleles. Due to their structural homology, unequivocally manifested by the organization of similar three-dimensional topolog...

The basal fungus Allomyces macrogynus (A. macrogynus) produces motile male gametes displaying well-studied chemotaxis toward their female counterparts. This chemotaxis is driven by sirenin, a sexual pheromone released by the female gametes. The pheromone evokes a large calcium influx in the motile gametes, which could proceed through the cation channel of sperm (CatSper) complex. Herein, we rep...

Attractiveness is a major component of sexual selection that is dependent on sexual characteristics, such as pheromone production, which often reflect an individual's fitness and reproductive potential. Aging is a process that results in a steady decline in survival and reproductive output, yet little is known about its effect on specific aspects of attractiveness. In this report we asked how a...

Pheromones can have profound effects on reproductive physiology and behavior in mammals. To investigate the neural circuits underlying these effects, we used a genetic transneuronal tracer to identify neurons that synapse with GnRH (LHRH) neurons, the key regulators of reproduction. We then asked whether the connected neurons are presynaptic or postsynaptic to GnRH neurons and analyzed their re...

The role of olfactory sexual attractants in the sex behavior of primates is discussed. These olfactory cues can prompt mounting, masturbation, and ejaculation, increase grooming behavior, and reduce aggressive behavior. In rhesus monkeys, the addition of phenylpropanoic and parahydroxyphenylpropanoic acids to a synthetic acid mixture has been shown to enhance the effectiveness of the syntheti...

Males of the noctuid moths, Heliothis virescens and H. subflexa locate mates based on species-specific responses to female-emitted pheromones that are composed of distinct blends of volatile compounds. We conducted genetic crosses between these two species and used AFLP marker-based mapping of backcross families (H. subflexa direction) to determine which of the 30 autosomes in these moths conta...

Electroantennogram (EAG) responses of male obliquebanded leafrollers, Choristoneura rosaceana (Harris), to the main component of its pheromone blend and traces of geometric isomer ((Z)11-14:Ac and (E)11-14:Ac, respectively) were recorded before and after 1 h of continuous exposure to pheromone in laboratory experiments, and 24h of exposure under field conditions. Concentrations of pheromone ran...

Throughout the animal kingdom, sexual pheromones are used for the attraction of mates and as courtship signals but also enable sexual isolation between species. In the parasitic wasp Lariophagus distinguendus, male courtship behaviour consisting of wing fanning, antennal stroking of the female antenna, and head nodding stimulates female receptivity leading to copulation. Recently L. distinguend...

The sex-inducing pheromone of the multicellular green alga Volvox carteri is a glycoprotein that triggers development of males and females at a concentration <10(-16) M. By differential screening of a cDNA library, two novel genes were identified that are transcribed under the control of this pheromone. Unexpectedly, one gene product was characterized as a lysozyme/chitinase, and the other gene...

Sexual reproduction occurs in two fundamentally different ways: by outcrossing, in which two distinct partners contribute nuclei, or by self-fertilization (selfing), in which both nuclei are derived from the same individual. Selfing is common in flowering plants, fungi, and some animal taxa. We investigated the genetic basis of selfing in the homothallic fungus Aspergillus nidulans. We demonstr...