Polinators in Peril - Are Illinois Native Bees Getting Smaller?

Why it matters. Pollination services provided by native bees are an important natural process, providing ~150 billion dollars globally in agricultural gains. A bee’s body size is a trait that is an important indicator of the nutritional environment. A loss of habitat results in a loss of rich nutritional environments as flowers and resource become more fragmented and scarcer. It has been discovered that a bee’s body size is a determinant of their foraging range. The smaller the bee, the less distance they can travel for food, therefor, the more susceptible they are to habitat loss and resource limitation

GEMS Student: Can Improved Diet Quality Alleviate Harmful Effects of Pesticides and Viruses in Honey Bees?

This study investigates interacting effects of viruses and pesticides within honey bees and how improved diet quality can mitigate these effects. This experiment allows a multivariate problem which exists in natural conditions of the honey bee community to be observed in a controlled cage bioassay. • The virus used in this study is the Israeli acute-paralysis virus (IAPV). Neonicotinoid thiamethoxam is the pesticide used in both trials shown in the ‘Results’ section. This experiment has not begun the use of the pyrethroid at this time

Effect of Varied Macronutrient Ratios on Honey Bee Tolerance to IAPV Infection

Honey bees are killed by Israeli acute paralysis virus (IAPV). Because this virus has no cure, it is important to lessen its impact on bees through proper nutrition. This project explores the effects of differing protein to lipid (P:L) ratios in pollen on honey bee susceptibility to this virus. Over three trials, bees in cages were incubated for 3 days to resemble hive conditions. Two doses of IAPV (10-3 & 10-2) and a negative control were used, along with five P:L ratios (1.5, 2.5, 11.5, 16.5, & 21.5:1) and a sucrose-only diet. These treatment groups were combined to create a total of 18 treatments (three doses by six diets). After feeding infected bees diets altered with either casein or canola oil (P or L) mortality was measured every 12 hours. Resulting data found significant differences in mortality rates between diet treatments among bees infected with a 10-2 dose. No significant differences between diets were found in the negative control and 10-3 groups

Juvenile hormone regulation of Drosophila aging

Background: Juvenile hormone (JH) has been demonstrated to control adult lifespan in a number of non-model insects where surgical removal of the corpora allata eliminates the hormone’s source. In contrast, little is known about how juvenile hormone affects adult Drosophila melanogaster. Previous work suggests that insulin signaling may modulate Drosophila aging in part through its impact on juvenile hormone titer, but no data yet address whether reduction of juvenile hormone is sufficient to control Drosophila life span. Here we adapt a genetic approach to knock out the corpora allata in adult Drosophila melanogaster and characterize adult life history phenotypes produced by reduction of juvenile hormone. With this system we test potential explanations for how juvenile hormone modulates aging. Results: A tissue specific driver inducing an inhibitor of a protein phosphatase was used to ablate the corpora allata while permitting normal development of adult flies. Corpora allata knockout adults had greatly reduced fecundity, inhibited oogenesis, impaired adult fat body development and extended lifespan. Treating these adults with the juvenile hormone analog methoprene restored all traits toward wildtype. Knockout females remained relatively long-lived even when crossed into a genotype that blocked all egg production. Dietary restriction further extended the lifespan of knockout females. In an analysis of expression profiles of knockout females in fertile and sterile backgrounds, about 100 genes changed in response to loss of juvenile hormone independent of reproductive state. Conclusions: Reduced juvenile hormone alone is sufficient to extend the lifespan of Drosophila melanogaster. Reduced juvenile hormone limits reproduction by inhibiting the production of yolked eggs, and this may arise because juvenile hormone is required for the post-eclosion development of the vitellogenin-producing adult fat body. Our data do not support a mechanism for juvenile hormone control of longevity simply based on reducing the physiological costs of egg production. Nor does the longevity benefit appear to function through mechanisms by which dietary restriction extends longevity. We identify transcripts that change in response to juvenile hormone independent of reproductive state and suggest these represent somatically expressed genes that could modulate how juvenile hormone controls persistence and longevity

Conclusive Evidence of Replication of a Plant Virus in Honeybees Is Lacking

The recent article by Li et al. (1) lacks adequate evidence to support the authors’ assertion that a plant virus propagates or replicates in honeybees. Instead, it is possible that tobacco ringspot virus (TRSV) virions associate with the honeybee and parasitic Varroa mites in the absence of TRSV replication

Transcriptomic responses to diet qualityand viral infection in Apis mellifera

Background Parts of Europe and the United States have witnessed dramatic losses in commercially managed honey bees over the past decade to what is considered an unsustainable extent. The large-scale loss of bees has considerable implications for the agricultural economy because bees are one of the leading pollinators of numerous crops. Bee declines have been associated with several interactive factors. Recent studies suggest nutritional and pathogen stress can interactively contribute to bee physiological declines, but the molecular mechanisms underlying interactive effects remain unknown. In this study, we provide insight into this question by using RNA-sequencing to examine how monofloral diets and Israeli acute paralysis virus inoculation influence gene expression patterns in bees. Results We found a considerable nutritional response, with almost 2000 transcripts changing with diet quality. The majority of these genes were over-represented for nutrient signaling (insulin resistance) and immune response (Notch signaling and JaK-STAT pathways). In our experimental conditions, the transcriptomic response to viral infection was fairly limited. We only found 43 transcripts to be differentially expressed, some with known immune functions (argonaute-2), transcriptional regulation, and muscle contraction. We created contrasts to explore whether protective mechanisms of good diet were due to direct effects on immune function (resistance) or indirect effects on energy availability (tolerance). A similar number of resistance and tolerance candidate differentially expressed genes were found, suggesting both processes may play significant roles in dietary buffering from pathogen infection. Conclusions Through transcriptional contrasts and functional enrichment analysis, we contribute to our understanding of the mechanisms underlying feedbacks between nutrition and disease in bees. We also show that comparing results derived from combined analyses across multiple RNA-seq studies may allow researchers to identify transcriptomic patterns in bees that are concurrently less artificial and less noisy. This work underlines the merits of using data visualization techniques and multiple datasets to interpret RNA-sequencing studies.Ope

Toward an integrative understanding of social behavior: new models and new opportunities.

Social interactions among conspecifics are a fundamental and adaptively significant component of the biology of numerous species. Such interactions give rise to group living as well as many of the complex forms of cooperation and conflict that occur within animal groups. Although previous conceptual models have focused on the ecological causes and fitness consequences of variation in social interactions, recent developments in endocrinology, neuroscience, and molecular genetics offer exciting opportunities to develop more integrated research programs that will facilitate new insights into the physiological causes and consequences of social variation. Here, we propose an integrative framework of social behavior that emphasizes relationships between ultimate-level function and proximate-level mechanism, thereby providing a foundation for exploring the full diversity of factors that underlie variation in social interactions, and ultimately sociality. In addition to identifying new model systems for the study of human psychopathologies, this framework provides a mechanistic basis for predicting how social behavior will change in response to environmental variation. We argue that the study of non-model organisms is essential for implementing this integrative model of social behavior because such species can be studied simultaneously in the lab and field, thereby allowing integration of rigorously controlled experimental manipulations with detailed observations of the ecological contexts in which interactions among conspecifics occur

Uporaba voltmetrije za određivanje tiola i metalotioneina male molekularne mase u krvi svinje (Sus scrofa domestica)

Metallothioneins (MT) play a key role in maintaining the homeostasis of essential metals and in protecting of cells against metal toxicity as well as cell oxidative damaging. The aim of this work is to propose a new approach for processing a biological sample for analysis of thiols including metallothioneins. Moreover, the proposed procedure is tested on quantification of MT and total thiol content in blood serum of pig (Sus scrofa domestica), which has not been previously been performed. The blood serum (10 ml) was collected and transferred to 0.2 M phosphate buffer (990 ml). The sample (100 × diluted) was placed in a thermomixer, where heat denaturation of most of the proteins proceeded. The processed blood serum sample was electrochemically measured to determine total content of thiols (cysteine, glutathione, metallothionein and other low molecular thermostable thiols) and content of MT. The average level of the thiols and MT were estimated as 165 ± 20 mM and 5.2 ± 0.6 mM, respectively.Metalotioneini (MT) igraju ključnu ulogu u održavanju homeostaze esencijalnih metala i u zaštiti od toksičnih metala te od oštećivanja stanice oksidacijom. Cilj ovog rada je predložiti novi pristup obradi bioloških uzoraka za analizu tiola, uključujući metalotioneine. Osim toga, predloženi postupak se testira pri kvantifikaciji MT i ukupnog sadržaja tiola u krvnom serumu svinje (Sus scrofa domestica), što se dosad nije radilo. Prikupljan je krvni serum (10 ml) te prebacivan u 0.2 M fosfatni pufer (990 ml). Uzorak (100 × razrijeđen) je stavljen u termomikser gdje se nastavila toplinska denaturacija većine proteina. Obrađeni uzorak seruma je elektrokemijski izmjeren da bi se odredio ukupni sadržaj tiola (cistein, glutation, metalotionein i drugi termostabilni tioli male molekularne mase) te sadržaj MT. Prosječna razina tiola i MT su procijenjeni na 165 ± 20 mM, odnosno 5.2 ± 0.6 mM