scholarly journals Juvenile hormone affects the development and strength of circadian rhythms in young bumble bee (Bombus terrestris) workers

2020 ◽  
Author(s):  
Atul Pandey ◽  
Uzi Motro ◽  
Guy Bloch
Keyword(s):  
Circadian Rhythms ◽  
Juvenile Hormone ◽  
Bombus Terrestris ◽  
Bumble Bee ◽  
Early Age ◽  
Ovarian Activity ◽  
Physiological Processes ◽  
The Social ◽  
Free Running ◽  
Wax Production

AbstractThe circadian and endocrine systems influence many physiological processes in animals, but little is known on the ways they interact in insects. We tested the hypothesis that juvenile hormone (JH) influences circadian rhythms in the social bumble bee Bombus terrestris. JH is the major gonadotropin in this species coordinating processes such as vitellogenesis, oogenesis, wax production, and behaviors associated with reproduction. It is unknown however, whether it also influences circadian processes. We topically treated newly-emerged bees with the allatoxin Precocene-I (P-I) to reduce circulating JH titers and applied the natural JH (JH-III) for replacement therapy. We repeated this experiment in three trials, each with bees from different source colonies. Measurements of ovarian activity confirmed that our JH manipulations were effective; bees treated with P-I had inactive ovaries, and this effect was fully reverted by subsequent JH treatment. We found that JH augments the strength of circadian rhythms and the pace of rhythm development in individually isolated newly emerged worker bees. JH manipulation did not affect the free-running circadian period, overall level of locomotor activity, or the amount of sleep. Given that acute manipulation at an early age produced relatively long-lasting effects, we propose that JH effect on circadian rhythms is mostly organizational, accelerating the development or integration of the circadian system.

scholarly journals Krüppel-Homologue 1 Mediates Hormonally-Regulated Dominance Rank in a Social Insect

2021 ◽  
Author(s):  
Atul Pandey ◽  
Guy Bloch
Keyword(s):  
Social Insect ◽  
Bombus Terrestris ◽  
Dominance Rank ◽  
Bumble Bee ◽  
Dominance Behavior ◽  
Social Hierarchies ◽  
Dominance Hierarchies ◽  
Multiple Factors ◽  
The Social ◽  
Wax Production

Dominance hierarchies are ubiquitous in invertebrates and vertebrates, but little is known on how genes influence dominance rank. Our gaps in knowledge are specifically significant concerning female hierarchies and in insects. To start filling these gaps we studied the social bumble bee Bombus terrestris, in which social hierarchies among females are common and functionally significant. Dominance rank in this bee is influenced by multiple factors, including juvenile hormone (JH) that is a major gonadotropin in this species. We tested the hypothesis that the JH responsive transcription factor Krüppel homologue 1 (Kr-h1) mediates hormonal influence on dominance behavior in the bumble bee. We first developed and validated a perfluorocarbon nanoparticles-based RNA interference protocol for knocking down Kr-h1 expression. We then used this procedure to show that Kr-h1 mediates the influence of JH not only on oogenesis and wax production, but also on aggression and dominance rank. To the best of our knowledge, this is the first study causally linking a gene to dominance rank in social insects, and one of only a few such studies in insects or in female hierarchies. These findings are important for determining whether there are general molecular principles governing dominance rank across gender and taxa.

scholarly journals Krüppel-homologue 1 Mediates Hormonally Regulated Dominance Rank in a Social Bee

Biology ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1188
Author(s):  
Atul Pandey ◽  
Guy Bloch
Keyword(s):  
Bombus Terrestris ◽  
Dominance Rank ◽  
Bumble Bee ◽  
Dominance Behavior ◽  
Social Hierarchies ◽  
Dominance Hierarchies ◽  
Multiple Factors ◽  
The Social ◽  
Wax Production ◽  
Social Bee

Dominance hierarchies are ubiquitous in invertebrates and vertebrates, but little is known on how genes influence dominance rank. Our gaps in knowledge are specifically significant concerning female hierarchies, particularly in insects. To start filling these gaps, we studied the social bumble bee Bombus terrestris, in which social hierarchies among females are common and functionally significant. Dominance rank in this bee is influenced by multiple factors, including juvenile hormone (JH) that is a major gonadotropin in this species. We tested the hypothesis that the JH responsive transcription factor Krüppel homologue 1 (Kr-h1) mediates hormonal influences on dominance behavior. We first developed and validated a perfluorocarbon nanoparticles-based RNA interference protocol for knocking down Kr-h1 expression. We then used this procedure to show that Kr-h1 mediates the influence of JH, not only on oogenesis and wax production, but also on aggression and dominance rank. To the best of our knowledge, this is the first study causally linking a gene to dominance rank in social insects, and one of only a few such studies on insects or on female hierarchies. These findings are important for determining whether there are general molecular principles governing dominance rank across gender and taxa.

scholarly journals Maternity-related plasticity in circadian rhythms of bumble-bee queens

2011 ◽  
Vol 278 (1724) ◽  
pp. 3510-3516 ◽  
Author(s):  
Ada Eban-Rothschild ◽  
Selma Belluci ◽  
Guy Bloch
Keyword(s):  
Life Cycle ◽  
Locomotor Activity ◽  
Circadian Rhythms ◽  
Circadian Clock ◽  
Bombus Terrestris ◽  
Colony Founding ◽  
Bumble Bee ◽  
Maternal Behaviour ◽  
Life Cycle Stages ◽  
Worker Caste

Unlike most animals studied so far in which the activity with no circadian rhythms is pathological or linked to deteriorating performance, worker bees and ants naturally care for their sibling brood around the clock with no apparent ill effects. Here, we tested whether bumble-bee queens that care alone for their first batch of offspring are also capable of a similar chronobiological plasticity. We monitored locomotor activity of Bombus terrestris queens at various life cycle stages, and queens for which we manipulated the presence of brood or removed the ovaries. We found that gynes typically emerged from the pupae with no circadian rhythms, but after several days showed robust rhythms that were not affected by mating or diapauses. Colony-founding queens with brood showed attenuated circadian rhythms, irrespective of the presence of ovaries. By contrast, queens that lost their brood switched again to activity with strong circadian rhythms. The discovery that circadian rhythms in bumble-bee queens are regulated by the life cycle and the presence of brood suggests that plasticity in the circadian clock of bees is ancient and related to maternal behaviour or physiology, and is not a derived trait that evolved with the evolution of the worker caste.

scholarly journals Juvenile hormone interacts with multiple factors to modulate aggression and dominance in groups of orphan bumble bee (Bombus terrestris) workers

2019 ◽  
Author(s):  
Atul Pandey ◽  
Uzi Motro ◽  
Guy Bloch
Keyword(s):  
Body Size ◽  
Juvenile Hormone ◽  
Replacement Therapy ◽  
Dominance Hierarchy ◽  
Bombus Terrestris ◽  
Dominance Rank ◽  
Bumble Bees ◽  
Bumble Bee ◽  
Multiple Factors ◽  
Similar Body

AbstractJuvenile hormone (JH) is a key regulator of insect development and reproduction. Given that JH commonly affects adult insect fertility, it has been hypothesized to also regulate behaviors such as dominance and aggression that are associated with reproduction. We tested this hypothesis in the bumble bee Bombus terrestris for which JH has been shown to be the major gonadotropin. We used the allatoxin Precocene-I (P-I) to reduce hemolymph JH titers and replacement therapy with the natural JH to revert this effect. In small orphan groups of workers with similar body size but mixed treatment, P-I treated bees showed lower aggressiveness, oogenesis, and dominance rank compared with control and replacement therapy treated bees. In similar groups in which all bees were treated similarly, there was a clear dominance hierarchy, even in P-I and replacement therapy treatment groups in which the bees showed similar levels of ovarian activation. In a similar experiment in which bees differed in body size, larger bees were more likely to be dominant despite their similar JH treatment and ovarian state. In the last experiment, we show that JH manipulation does not affect dominance rank in groups that had already established a stable dominance hierarchy. These findings solve previous ambiguities concerning whether or not JH affects dominance in bumble bees. JH positively affects dominance, but bees with similar levels of JH can nevertheless establish dominance hierarchies. Thus, multiple factors including JH, body size, and previous experience affect dominance and aggression in social bumble bees.

OPTIMALISASI PENGELOLAAN PERKEMBANGAN SOSIAL EMOSI ANAK USIA DINI

Edupedia ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 59-66
Author(s):  
Khulusinniyah ◽  
Farhatin Masruroh
Keyword(s):  
Early Childhood ◽  
Social Development ◽  
Social Relationships ◽  
Emotional Development ◽  
Emotional Reactions ◽  
Early Age ◽  
Important Thing ◽  
Emotion Development ◽  
Social Emotion ◽  
The Social

The social-emotionaldevelopment of children is important to be developed from an early age. The emotionaldevelopment in early childhood, takes place simultaneously with their social development. Even there is claim that their emotional development is influenced by their social development. Itcaused by the emotional reactions displayed by early childhood as a response to the social relationships that they live with other people. The emotional development of early childhood can also affect the sustainability of social relationships. Stimulation is an important thing to give by early childhood educators and parents so they can optimize their social emotion development. With this treatment, they can grow into the life ready person in facing the complex future.

I doveri della moglie secondo gli insegnamenti di alcuni predicatori e scrittori tardomedievali

2019 ◽  
Vol 110 (1) ◽  
pp. 31-45
Keyword(s):  
Mortality Rate ◽  
Young Children ◽  
Social Status ◽  
Free Time ◽  
Early Age ◽  
Social Standing ◽  
Raising Children ◽  
The Social ◽  
Medieval Europe ◽  
The Future

The society of medieval Europe had specific expectations for marriageable girls. From an early age girls were taught how to be wives and mothers, for example by being entrusted with the care of their younger siblings. The girls learned everything they would need in the future by observation. According to the teachings of preachers and writers at the time, girls, irrespective of their social status, were not meant to remain idle, as there were fears that with too much free time on their hands, they might spend it contemplating their looks, practising gestures that were to attract the attention of men or spending time alone in the streets and squares, thus exposing themselves to a variety of dangers. A wife was expected to bear a lot of children, preferably boys, because the mortality rate among young children was high at the time. Wifely duties also included raising children, at least until they were taken over by, for example, a tutor hired by the father, managing the household and ensuring every possible comfort for the husband. As Gilbert of Tournai noted, it was the mother who was expected to bring up the children in faith and to teach them good manners. The duties of the wife obviously depended on her social standing — different duties were expected from the wives of noblemen than from women lower down on the social ladder, who often had to help their husbands, in addition to doing everyday chores.

scholarly journals Shared Components of the FRQ-Less Oscillator and TOR Pathway Maintain Rhythmicity in Neurospora

2021 ◽  
pp. 074873042199994
Author(s):  
Rosa Eskandari ◽  
Lalanthi Ratnayake ◽  
Patricia L. Lakin-Thomas
Keyword(s):  
Circadian Rhythms ◽  
Clock Genes ◽  
Nutrient Sensing ◽  
Mass Spectrometry Analysis ◽  
Growth Responses ◽  
Tor Pathway ◽  
Spectrometry Analysis ◽  
Binding Partner ◽  
Binding Partners ◽  
Free Running

Molecular models for the endogenous oscillators that drive circadian rhythms in eukaryotes center on rhythmic transcription/translation of a small number of “clock genes.” Although substantial evidence supports the concept that negative and positive transcription/translation feedback loops (TTFLs) are responsible for regulating the expression of these clock genes, certain rhythms in the filamentous fungus Neurospora crassa continue even when clock genes ( frq, wc-1, and wc-2) are not rhythmically expressed. Identification of the rhythmic processes operating outside of the TTFL has been a major unresolved area in circadian biology. Our lab previously identified a mutation ( vta) that abolishes FRQ-less rhythmicity of the conidiation rhythm and also affects rhythmicity when FRQ is functional. Further studies identified the vta gene product as a component of the TOR (Target of Rapamycin) nutrient-sensing pathway that is conserved in eukaryotes. We now report the discovery of TOR pathway components including GTR2 (homologous to the yeast protein Gtr2, and RAG C/D in mammals) as binding partners of VTA through co-immunoprecipitation (IP) and mass spectrometry analysis using a VTA-FLAG strain. Reciprocal IP with GTR2-FLAG found VTA as a binding partner. A Δ gtr2 strain was deficient in growth responses to amino acids. Free-running conidiation rhythms in a FRQ-less strain were abolished in Δ gtr2. Entrainment of a FRQ-less strain to cycles of heat pulses demonstrated that Δ gtr2 is defective in entrainment. In all of these assays, Δ gtr2 is similar to Δ vta. In addition, expression of GTR2 protein was found to be rhythmic across two circadian cycles, and functional VTA was required for GTR2 rhythmicity. FRQ protein exhibited the expected rhythm in the presence of GTR2 but the rhythmic level of FRQ dampened in the absence of GTR2. These results establish association of VTA with GTR2, and their role in maintaining functional circadian rhythms through the TOR pathway.

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