The detection and amplification of extracellular signals requires the involvement of multiple protein components. In mammalian cells the receptor of activated C kinase (RACK1) is an important scaffolding protein for signal transduction networks. Further, it also performs a critical function in regulating the cell cycle by modulating the G1/S transition. Many eukaryotic cells express RACK1 ortho...

All aphid species studied so far share the same sex pheromone components, nepetalactol and nepetalactone. Variation by different enantiomers and blends of the two components released by different aphid species are limited and can only partially explain species-specific attraction of males to females. While some host-plant odours are known to enhance specific attraction of aphid species, herbivo...

Pheromonal signals provide specific information concerning the identity, gender, endocrine, and social status of different members of the population in a variety of mammals (Halpern, 1987; Wysocki and Meredith, 1987). Pheromones in urine excreted from male and female rats induce various changes in gonadal functions such as reflex ovulation in the absence of coitus and mounting (Johns et al., 19...

In all animals, sleep pressure is under continuous tight regulation. It is universally accepted that this regulation arises from a two-process model, integrating both a circadian and a homeostatic controller. Here we explore the role of environmental social signals as a third, parallel controller of sleep homeostasis and sleep pressure. We show that, in Drosophila melanogaster males, sleep pres...

Insect cuticular hydrocarbons (CHCs) serve as important intersexual signaling chemicals and generally show variation between the sexes, but little is known about generation of sexually dimorphic (SDHCs) in insects. In this study, we report molecular mechanism biological significance that underlie SDHC German cockroach Blattella germanica . Sexually mature females possess more C29 CHCs, especial...

BACKGROUND Why do males and females behave differently? Sexually dimorphic behaviors could arise from sex-specific neurons or by the modification of circuits present in both sexes. C. elegans males exhibit different behaviors than hermaphrodites. Although there is a single class of sex-specific sensory neurons in the head of males, most of their neurons are part of a core nervous system also pr...

A conserved MAP kinase cascade is central to signal transduction in both simple and complex eukaryotes. In the yeast Schizosaccharomyces pombe, Byr2, a homolog of mammalian MAPK/ERK kinase kinase and Saccharomyces cerevisiae STE11, is required for pheromone-induced sexual differentiation. A screen for S. pombe proteins that interact with Byr2 in a two-hybrid system led to the isolation of Ste4,...

Organisms partition resources into life-history traits in order to maximise fitness over their expected lifespan. For the males of many species fitness is determined by qualitative and quantitative aspects of costly sexual signals: The notion that epigamic traits are costly forms the cornerstone of those theories that propose parasites drive sexual selection. Consequently studies examining this...

The objective of this work was to characterize the sexual behavior of the citrus leafminer, Phyllocnistis citrella Stainton, as the foundation for the isolation, identification, and synthesis of the complete sex pheromone of this species. Mating occurred in a time window of 2h, starting 1h before the onset of photophase. The large majority of tested insects mated in the first two days after eme...