תפריט נגישות
ניגודיות עדינהניגודיות גבוהה
מונוכרום
הדגשת קישורים
חסימת אנימציה
פונט קריא
סגור
איפוס הגדרות נגישות
להורדת מודול נגישות חינם תפריט נגישותניגודיות עדינהניגודיות גבוההמונוכרוםהדגשת קישוריםחסימת אנימציהפונט קריאסגוראיפוס הגדרות נגישותלהורדת מודול נגישות חינםKatzav-Gozansky, T. and Hefetz, A. - Dept. of Zoology, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel Aviv 69978
Despite the genetic similarity between queen and worker honeybees, the two castes differ in their behavior and physiology. Queen presence is mediated by queen-specific pheromones that direct many worker behaviors. These pheromones are produced by multiple glands, each of which produces a multi-component bouquet. One of the main differences between the castes is worker sterility. Worker sterility is known to be queen-dependent, because under hopeless queenless conditions workers rapidly develop ovaries and produce males. In addition, recently it was found that castespecific pheromones in the honeybee do not result from a fixed caste-specific biosynthetic pathway, but rather show plasticity affected by the social environment and correlated with the physiological condition. Queenless (QL), but not queenright (QR), workers develop ovaries and possess in their Dufour's gland the long-chain esters characteristic of the queen's secretion. Moreover, in vivo incorporation studies showed that esters biosynthesis reflects the social environment of the bee studies. In contrast, glands incubated in vitro always showed ester biosynthesis. These results led us to the hypothesis that pheromone biosynthesis in workers' Dufour's gland is under neuroendocrine regulation, which in turn is queen-regulated by the queen through primary pheromone(s), resulting in esters inhibition. To test this hypothesis we monitored the effect of brain extracts of queens or QR workers on the biosynthesis of queen Dufour's esters in isolated glands of QR workers in vitro. Unpredictably, worker crude brain extract activated, rather than inhibited, the queen-like esters biosynthesis. One possibility is that the queen pheromone inhibits the release of Dufour's activating factor(s) from worker brains. In the absence of the queen, the inhibition is activated and the release of the brain-activating factor occurs, triggering a queen-like biosynthetic pathway in the Dufour's gland. Understanding the regulation of pheromone production in view of reproductive skew and its regulation is an important issue for understanding the evolution of sociality. [L]
Katzav-Gozansky, T. and Hefetz, A. - Dept. of Zoology, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel Aviv 69978
Despite the genetic similarity between queen and worker honeybees, the two castes differ in their behavior and physiology. Queen presence is mediated by queen-specific pheromones that direct many worker behaviors. These pheromones are produced by multiple glands, each of which produces a multi-component bouquet. One of the main differences between the castes is worker sterility. Worker sterility is known to be queen-dependent, because under hopeless queenless conditions workers rapidly develop ovaries and produce males. In addition, recently it was found that castespecific pheromones in the honeybee do not result from a fixed caste-specific biosynthetic pathway, but rather show plasticity affected by the social environment and correlated with the physiological condition. Queenless (QL), but not queenright (QR), workers develop ovaries and possess in their Dufour's gland the long-chain esters characteristic of the queen's secretion. Moreover, in vivo incorporation studies showed that esters biosynthesis reflects the social environment of the bee studies. In contrast, glands incubated in vitro always showed ester biosynthesis. These results led us to the hypothesis that pheromone biosynthesis in workers' Dufour's gland is under neuroendocrine regulation, which in turn is queen-regulated by the queen through primary pheromone(s), resulting in esters inhibition. To test this hypothesis we monitored the effect of brain extracts of queens or QR workers on the biosynthesis of queen Dufour's esters in isolated glands of QR workers in vitro. Unpredictably, worker crude brain extract activated, rather than inhibited, the queen-like esters biosynthesis. One possibility is that the queen pheromone inhibits the release of Dufour's activating factor(s) from worker brains. In the absence of the queen, the inhibition is activated and the release of the brain-activating factor occurs, triggering a queen-like biosynthetic pathway in the Dufour's gland. Understanding the regulation of pheromone production in view of reproductive skew and its regulation is an important issue for understanding the evolution of sociality. [L]
