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Soybean Arogenate Dehydratases (Gmadts): Involvement In The Cytosolic Isoflavonoid Metabolon Or Trans-Organelle Continuity?, Emily J. Clayton, Nishat S. Islam, Kelsey Pannunzio, Kuflom Kuflu, Ramtin Sirjani, Susanne E. Kohalmi, Sangeeta Dhaubhadel Jan 2024

Soybean Arogenate Dehydratases (Gmadts): Involvement In The Cytosolic Isoflavonoid Metabolon Or Trans-Organelle Continuity?, Emily J. Clayton, Nishat S. Islam, Kelsey Pannunzio, Kuflom Kuflu, Ramtin Sirjani, Susanne E. Kohalmi, Sangeeta Dhaubhadel

Biology Publications

Soybean (Glycine max) produces a class of phenylalanine (Phe) derived specialized metabolites, isoflavonoids. Isoflavonoids are unique to legumes and are involved in defense responses in planta, and they are also necessary for nodule formation with nitrogen-fixing bacteria. Since Phe is a precursor of isoflavonoids, it stands to reason that the synthesis of Phe is coordinated with isoflavonoid production. Two putative AROGENATE DEHYDRATASE (ADT) isoforms were previously co-purified with the soybean isoflavonoid metabolon anchor ISOFLAVONE SYNTHASE2 (GmIFS2), however the GmADT family had not been characterized. Here, we present the identification of the nine member GmADT family. We determined that the GmADTs …


Msspl9 Modulates Nodulation Under Nitrate Sufficiency Condition In Medicago Sativa, Vida Nasrollahi, Gamalat Allam, Susanne E. Kohalmi, Abdelali Hannoufa Jun 2023

Msspl9 Modulates Nodulation Under Nitrate Sufficiency Condition In Medicago Sativa, Vida Nasrollahi, Gamalat Allam, Susanne E. Kohalmi, Abdelali Hannoufa

Biology Publications

Nodulation in Leguminous spp. is induced by common environmental cues, such as low nitrogen availability conditions, in the presence of the specific Rhizobium spp. in the rhizosphere. Medicago sativa (alfalfa) is an important nitrogen-fixing forage crop that is widely cultivated around the world and relied upon as a staple source of forage in livestock feed. Although alfalfa’s relationship with these bacteria is one of the most efficient between rhizobia and legume plants, breeding for nitrogen-related traits in this crop has received little attention. In this report, we investigate the role of Squamosa-Promoter Binding Protein-Like 9 (SPL9), a target of miR156, …


Plant Production Of A Virus-Like Particle-Based Vaccine Candidate Against Porcine Reproductive And Respiratory Syndrome, Jordan T. Vanderburgt, Ondre Harper, Christopher P. Garnham, Susanne E. Kohalmi, Rima Menassa Jan 2023

Plant Production Of A Virus-Like Particle-Based Vaccine Candidate Against Porcine Reproductive And Respiratory Syndrome, Jordan T. Vanderburgt, Ondre Harper, Christopher P. Garnham, Susanne E. Kohalmi, Rima Menassa

Biology Publications

Porcine reproductive and respiratory syndrome (PRRS) is a disease leading to spontaneous abortions and stillbirths in sows and lowered life quality and expectancy in growing pigs. PRRS is prevalent worldwide and has significant economic impacts to swine industries around the globe. Co-expression of the two most abundant proteins in the viral envelope, the matrix protein (M) and glycosylated protein 5 (GP5), can produce a neutralizing immune response for the virus providing a potentially effective subunit vaccine against the disease, but these proteins are difficult to express. The goal of this research was to display antigenic portions of the M and …


Localization Of Arabidopsis Glucan Synthase-Like 5, 8, And 12 To Plasmodesmata Andthe Gsl8-Dependent Role Of Pdlp5 In Regulating Plasmodesmal Permeability, Behnaz Saatian, Susanne Kohalmi, Yuhai Cui Jan 2023

Localization Of Arabidopsis Glucan Synthase-Like 5, 8, And 12 To Plasmodesmata Andthe Gsl8-Dependent Role Of Pdlp5 In Regulating Plasmodesmal Permeability, Behnaz Saatian, Susanne Kohalmi, Yuhai Cui

Biology Publications

Cell-to-cell communication via membranous channels called plasmodesmata (PD) plays critical rolesduring plant development and in response to biotic and abiotic stresses. Several enzymes and receptor-like proteins (RLPs), including Arabidopsis thaliana glucan synthase-likes (GSLs), also known as callosesynthases (CALSs), and PD-located proteins (PDLPs), have been implicated in plasmodesmal permeabilityregulation and intercellular communication. Localization of PDLPs to punctate structures at the cellperiphery and their receptor-like identity have raised the hypothesis that PDLPs are involved in theregulation of symplastic trafficking during plant development and in response to endogenous andexogenous signals. Indeed, it was shown that PDLP5 could limit plasmodesmal permeability throughinducing an increase …


A Kin-Selection Model Of Fairness In Heterogeneous Populations, Geoff Wild, Veronica J. Flear, Graham J. Thompson Jan 2023

A Kin-Selection Model Of Fairness In Heterogeneous Populations, Geoff Wild, Veronica J. Flear, Graham J. Thompson

Biology Publications

Humans and other primates exhibit pro-social preferences for fairness. These preferences are thought to be reinforced by strong reciprocity, a policy that rewards fair actors and punishes unfair ones. Theories of fairness based on strong reciprocity have been criticized for overlooking the importance of individual differences in socially heterogeneous populations. Here, we explore the evolution of fairness in a heterogeneous population. We analyse the Ultimatum Game in cases where players’ roles in the game are determined by their status. Importantly, our model allows for non-random pairing of players, and so we also explore the role played by kin selection in …


Long-Term Winter-Site Fidelity In Song Sparrows (Melospiza Melodia), Tosha R. Kelly, Keith A. Hobson, Garth @. Casbourn, Elizabeth A. Macdougall-Shackleton, Scott A. Macdougall-Shackleton Jun 2022

Long-Term Winter-Site Fidelity In Song Sparrows (Melospiza Melodia), Tosha R. Kelly, Keith A. Hobson, Garth @. Casbourn, Elizabeth A. Macdougall-Shackleton, Scott A. Macdougall-Shackleton

Biology Publications

In migratory animals, the degree to which individuals return to the same wintering sites across multiple years can affect fitness and population dynamics, and thus has important implications for conservation. Despite this, long-term evaluations of wintering-site fidelity are rare for migratory birds: many populations are intensively studied on their breeding grounds but tracking the migratory movements of small birds once they leave the breeding grounds is challenging. To evaluate patterns of overwintering location and fidelity, we collected winter-grown claw tissue from 301 Song Sparrows (Melospiza melodia; 449 samples) captured in spring at their breeding grounds over six consecutive …


No Evidence That Songbirds Use Odour Cues To Avoid Malaria-Infected Conspecifics, Leanne A. Grieves, Elizabeth A. Macdougall-Shackleton Jun 2022

No Evidence That Songbirds Use Odour Cues To Avoid Malaria-Infected Conspecifics, Leanne A. Grieves, Elizabeth A. Macdougall-Shackleton

Biology Publications

Many animals have evolved mechanisms to detect and avoid parasitized conspecifics, primarily through odour cues, but whether birds are capable of odour-mediated parasite avoidance is unknown. Recently, we showed that exposing song sparrows (Melospiza melodia) to avian malaria parasites (Plasmodium sp.) alters the chemical composition of their preen oil, which is the major source of body odour in birds. Here, we presented song sparrows with preen oil from uninfected (sham-inoculated) and malaria-infected conspecifics, predicting that birds would spend more time with odour cues from uninfected than infected birds. Birds without detectable malarial infections spent about 50% more …


Seasonal Migration Distance Varies With Natal Dispersal And Predicts Parasitic Infection In Song Sparrows, Tosha R. Kelly, Heather L. Macgillivray, Yanina Sarquis-Adamson, Matthew J. Watson, Keith A. Hobson, Elizabeth A. Macdougall-Shackleton May 2022

Seasonal Migration Distance Varies With Natal Dispersal And Predicts Parasitic Infection In Song Sparrows, Tosha R. Kelly, Heather L. Macgillivray, Yanina Sarquis-Adamson, Matthew J. Watson, Keith A. Hobson, Elizabeth A. Macdougall-Shackleton

Biology Publications

Seasonal migration and natal dispersal represent the major large-scale movements in the lives of animals. Individuals that are relatively prone to movement and exploration might thus be more likely to disperse and also to migrate farther. Such movement might be either negatively associated with parasitic infection (if infection prevents hosts from successful long-distance migration) or positively associated (e.g. if longer-distance migrants encounter more abundant or more diverse parasites). We examined whether natal dispersal tendency predicts seasonal migration distance in song sparrows (Melospiza melodia) and whether migration distance predicts infection with bloodborne parasites upon arrival at the breeding grounds. …


Fear Of Large Carnivores Is Tied To Ungulate Habitat Use: Evidence From A Bifactorial Experiment, Haley K. Epperly, Michael Clinchy, Liana Y. Zanette, Robert A. Mcceery Dec 2021

Fear Of Large Carnivores Is Tied To Ungulate Habitat Use: Evidence From A Bifactorial Experiment, Haley K. Epperly, Michael Clinchy, Liana Y. Zanette, Robert A. Mcceery

Biology Publications

The fear large carnivores inspire in large ungulates has been argued to have cascading effects down food webs. However, a direct link between ungulate habitat use and their fear of large carnivores has not been experimentally tested. To fill this critical gap, we conducted a bi-factorial experiment in an African savanna. We removed shrub cover and broadcast large carnivore vocalizations (leopard, hyena, dog) or non-threatening control vocalizations in both experimentally cleared and shrubby control sites. We recorded the proactive (frequency of visitation) and reactive (fleeing or vigilance) responses of multiple prey (impala, warthog, nyala and bushbuck). Critically, we found a …


Comparing Apples And Oranges (And Blueberries And Grapes): Fruit Type Affects Development And Cold-Susceptibility Of Immature Drosophila Suzukii, Yanira Jiménez Padilla, Laura V. Ferguson, Brent J. Sinclair Aug 2020

Comparing Apples And Oranges (And Blueberries And Grapes): Fruit Type Affects Development And Cold-Susceptibility Of Immature Drosophila Suzukii, Yanira Jiménez Padilla, Laura V. Ferguson, Brent J. Sinclair

Biology Publications

Drosophila suzukii is a cosmopolitan polyphagous pest on unripe soft-skinned fruits. We sought to determine 1) temperature treatments that could be used to kill immature D. suzukii in fruit or packaging, and 2) whether development on different fruits led to differences in cold tolerance of immature D. suzukii. We reared animals from egg on a banana-based laboratory diet and diets made of apple, blueberry, cherry, grape, orange, raspberry, or strawberry homogenate in agar, and measured development time, adult body size, and cold tolerance. Diet type had complex effects on development time; in particular, flies reared on apple- or blueberry-based …


Persistence Of Diet Effects On The Drosophila Suzukii Microbiota, Yanira Jiménez Padilla, Ebenezer Esan, Kevin D. Floate, Brent J. Sinclair Aug 2020

Persistence Of Diet Effects On The Drosophila Suzukii Microbiota, Yanira Jiménez Padilla, Ebenezer Esan, Kevin D. Floate, Brent J. Sinclair

Biology Publications

The insect commensal microbiota consists of prokaryotes and eukaryotes. The effect of diet and the persistence of the gut microbiota in Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) are not well-understood. We transferred subsets of a single population of D. suzukii to different fruit-based diets (blueberry, raspberry, and strawberry) for three generations and then returned them to a common, banana-based, laboratory diet. We used 16S (bacteria) and ITS (fungi) sequencing of female endosymbiont-free flies to identify the microbiota. We identified 2700 bacterial and 350 fungal OTUs; there was no correlation between the number of bacterial and fungal OTUs in a sample. Bacterial …


Dissection Of Anoplophora Glabripennis (Coleoptera: Cerambycidae) Larval Tissues For Physiological And Molecular Studies, Alex S. Torson, Lauren E. Des Marteaux, Susan Bowman, Meng Lei Zhang, Kevin Ong, Daniel Doucet, Brent J Sinclair, Amanda D. Roe Jun 2020

Dissection Of Anoplophora Glabripennis (Coleoptera: Cerambycidae) Larval Tissues For Physiological And Molecular Studies, Alex S. Torson, Lauren E. Des Marteaux, Susan Bowman, Meng Lei Zhang, Kevin Ong, Daniel Doucet, Brent J Sinclair, Amanda D. Roe

Biology Publications

Many biological processes are partitioned among organs and tissues, necessitating tissue-specific or organ-specific analysis (particularly for comparative -omics studies). Standardised techniques for tissue identification and dissection are therefore imperative for comparing among studies. Here we describe dissection protocols for isolating six key tissues/organs from larvae of the Asian longhorned beetle, Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae): the supraoesophageal ganglion, posterior midgut, hindgut, Malpighian tubules, fat body, and thoracic muscle. We also describe how to extract haemolymph and preserve whole larvae for measurements such as protein, lipid, and carbohydrate content. We include dissection protocols for both fresh-killed and previously frozen specimens. Although …


Thermal Variability And Plasticity Drive The Outcome Of A Host-Pathogen Interaction, Laura V. Ferguson, Brent J. Sinclair Apr 2020

Thermal Variability And Plasticity Drive The Outcome Of A Host-Pathogen Interaction, Laura V. Ferguson, Brent J. Sinclair

Biology Publications

Variable, changing, climates may affect each participant in a biotic interaction differently. We explored the effects of temperature and plasticity on the outcome of a host-pathogen interaction to try to predict the outcomes of infection under fluctuating temperatures. We infected Gryllus veletis crickets with the entomopathogenic fungus Metarhizium brunneum under constant (6 °C, 12 °C, 18 °C or 25 °C) or fluctuating temperatures (6 °C to 18 °C or 6 °C to 25 °C). We also acclimated crickets and fungi to constant or fluctuating conditions. Crickets acclimated to fluctuating conditions survived best under constant conditions if paired with warm-acclimated fungus. …


Playback Of Predator Calls Inhibits And Delays Dawn Singing In A Songbird Community, Peter Santema, Mihai Valcu, Michael Clinchy, Liana Zanette, Bart Kempenaers Sep 2019

Playback Of Predator Calls Inhibits And Delays Dawn Singing In A Songbird Community, Peter Santema, Mihai Valcu, Michael Clinchy, Liana Zanette, Bart Kempenaers

Biology Publications

Recent studies have demonstrated that experimental increases in perceived predation risk can substantially impair breeding behavior and reduce reproductive success. Perceived predation risk may also occur in the context of sexual signaling, with potential consequences for sexual selection. In songbirds, singing at dawn is an important sexual signal but may also attract predators. Here, we report on 2 experiments designed to test whether perceived predation risk affects the occurrence and timing of dawn singing in a songbird community. In a pilot experiment, we broadcast predator playbacks intermittently across half a forest plot and nonpredator playbacks across the other half throughout …


Gut Yeasts Do Not Improve Desiccation Survival In Drosophila Melanogaster, Joanne M. Tang, Yanira Jiménez Padilla, Marc-André Lachance, Brent J. Sinclair Jul 2019

Gut Yeasts Do Not Improve Desiccation Survival In Drosophila Melanogaster, Joanne M. Tang, Yanira Jiménez Padilla, Marc-André Lachance, Brent J. Sinclair

Biology Publications

A healthy gut microbiota generally improves the performance of its insect host. Although the effects can be specific to the species composition of the microbial community, the role of gut microbiota in determining water balance has not been well explored. We used axenic and gnotobiotic (reared with a known microbiota) Drosophila melanogaster to test three hypotheses about the effects of gut yeasts on the water balance of adult flies: 1) that gut yeasts would improve desiccation survival in adult flies; 2) that larval yeasts would improve adult desiccation survival; 3) that the effects would be species-specific, such that yeasts closely …


Laboratory Acclimation To Autumn-Like Conditions Induces Freeze Tolerance In The Spring Field Cricket Gryllus Veletis (Orthoptera: Gryllidae), Jantina Toxopeus, Alexander H. Mckinnon, Tomáš Štětina, Kurtis F. Turnbull, Brent J Sinclair Jan 2019

Laboratory Acclimation To Autumn-Like Conditions Induces Freeze Tolerance In The Spring Field Cricket Gryllus Veletis (Orthoptera: Gryllidae), Jantina Toxopeus, Alexander H. Mckinnon, Tomáš Štětina, Kurtis F. Turnbull, Brent J Sinclair

Biology Publications

Many temperate insects encounter temperatures low enough to freeze their body fluids. Remarkably, some insects are freeze-tolerant, surviving this internal ice formation. However, the mechanisms underlying freeze tolerance are not well-understood, in part due to a lack of tractable model organisms. We describe a novel laboratory model to study insect freeze tolerance, the spring field cricket Gryllus veletis (Orthopera: Gryllidae). Following acclimation to six weeks of decreasing temperature and photoperiod, G. veletis become freeze-tolerant, similar to those exposed to natural autumn conditions in London, Ontario, Canada. Acclimated crickets suppress their metabolic rate by c. 33%, and survive freezing for up …


The Effect Of Cold Acclimation On Active Ion Transport In Cricket Ionoregulatory Tissues., Lauren E Des Marteaux, Soheila Khazraeenia, Gil Y Yerushalmi, Andrew Donini, Natalia G Li, Brent J Sinclair Feb 2018

The Effect Of Cold Acclimation On Active Ion Transport In Cricket Ionoregulatory Tissues., Lauren E Des Marteaux, Soheila Khazraeenia, Gil Y Yerushalmi, Andrew Donini, Natalia G Li, Brent J Sinclair

Biology Publications

Cold-acclimated insects defend ion and water transport function during cold exposure. We hypothesized that this is achieved via enhanced active transport. The Malpighian tubules and rectum are likely targets for such transport modifications, and recent transcriptomic studies indicate shifts in Na+-K+ ATPase (NKA) and V-ATPase expression in these tissues following cold acclimation. Here we quantify the effect of cold acclimation (one week at 12 °C) on active transport in the ionoregulatory organs of adult Gryllus pennsylvanicus field crickets. We compared primary urine production of warm- and cold-acclimated crickets in excised Malpighian tubules via Ramsay assay at a range of temperatures …


Seasonal Shifts In The Insect Gut Microbiome Are Concurrent With Changes In Cold Tolerance And Immunity, Laura V. Ferguson, Pranav Dhakal, Jacqueline E. Lebenzon, David E. Heinrichs, Carol Bucking, Brent Sinclair Jan 2018

Seasonal Shifts In The Insect Gut Microbiome Are Concurrent With Changes In Cold Tolerance And Immunity, Laura V. Ferguson, Pranav Dhakal, Jacqueline E. Lebenzon, David E. Heinrichs, Carol Bucking, Brent Sinclair

Biology Publications

  1. Seasonal changes in the environment, such as varying temperature, have the potential to change the functional relationship between ectothermic animals, such as insects, and their microbiomes. Our objectives were to determine: (a) whether seasonal changes in temperature shift the composition of the insect gut microbiome, and (b) whether changes in the microbiome are concomitant with changes in the physiology of the host, including the immune system and response to cold.
  2. We exposed laboratory populations of the spring field cricket, Gryllus veletis (Orthoptera: Gryllidae), to simulated overwintering conditions in both a laboratory microcosm and a field‐like microcosm containing soil and leaves. …


Effects Of Cold Acclimation On Rectal Macromorphology, Ultrastructure, And Cytoskeletal Stability In Gryllus Pennsylvanicus Crickets., Lauren E Des Marteaux, Joseph R Stinziano, Brent J Sinclair Jan 2018

Effects Of Cold Acclimation On Rectal Macromorphology, Ultrastructure, And Cytoskeletal Stability In Gryllus Pennsylvanicus Crickets., Lauren E Des Marteaux, Joseph R Stinziano, Brent J Sinclair

Biology Publications

Cold-acclimated insects maintain ion and water balance in the cold, potentially by reducing permeability or increasing diffusion distance across ionoregulatory epithelia such as the rectum. We explored whether cold acclimation induces structural modifications that minimize water and ion diffusion across the rectum and maintain rectal cell integrity. We investigated rectal structure and cytoskeletal stability in chill-susceptible adult Gryllus pennsylvanicus crickets acclimated for one week to either warm (25 °C) or cold (12 °C) conditions. After acclimation, we used light and transmission electron microscopy to examine rectal macromorphology and rectal pad paracellular ultrastructure. We also used fluorescence microscopy and a filamentous-actin …


Insect Immunity Varies Idiosyncratically During Overwintering., Laura V Ferguson, Brent J Sinclair Jun 2017

Insect Immunity Varies Idiosyncratically During Overwintering., Laura V Ferguson, Brent J Sinclair

Biology Publications

Overwintering insects face multiple stressors, including pathogen and parasite pressures that shift with seasons. However, we know little of how the insect immune system fluctuates with season, particularly in the overwintering period. To understand how immune activity changes across autumn, winter, and spring, we tracked immune activity of three temperate insects that overwinter as larvae: a weevil (Curculio sp., Coleoptera), gallfly (Eurosta solidaginis, Diptera), and larvae of the lepidopteran Pyrrharctia isabella. We measured baseline circulating hemocyte numbers, phenoloxidase activity, and humoral antimicrobial activity, as well as survival of fungal infection and melanization response at 12°C and 25°C to capture any …


Thermal Preference And Performance In A Sub-Antarctic Caterpillar: A Test Of The Coadaptation Hypothesis And Its Alternatives., Tanya M Haupt, Brent J Sinclair, Steven L Chown Apr 2017

Thermal Preference And Performance In A Sub-Antarctic Caterpillar: A Test Of The Coadaptation Hypothesis And Its Alternatives., Tanya M Haupt, Brent J Sinclair, Steven L Chown

Biology Publications

Physiological ecologists have long assumed that thermoregulatory behaviour will evolve to optimise physiological performance. The coadaptation hypothesis predicts that an animal's preferred body temperature will correspond to the temperature at which its performance is optimal. Here we use a strong inference approach to examine the relationship between thermal preference and locomotor performance in the caterpillars of a wingless sub-Antarctic moth, Pringleophaga marioni Viette (Tineidae). The coadaptation hypothesis and its alternatives (suboptimal is optimal, thermodynamic effect, trait variation) are tested. Compared to the optimal movement temperature (22.5°C for field-fresh caterpillars and 25, 20, 22.5, 25 and 20°C following seven day acclimations …


Do Large Carnivores And Mesocarnivores Have Redundant Impacts On Intertidal Prey?, Justin P. Suraci, Michael Clinchy, Liana Y. Zanette Jan 2017

Do Large Carnivores And Mesocarnivores Have Redundant Impacts On Intertidal Prey?, Justin P. Suraci, Michael Clinchy, Liana Y. Zanette

Biology Publications

The presence of large carnivores can affect lower trophic levels by suppressing mesocarnivores and reducing their impacts on prey. The mesopredator release hypothesis therefore predicts prey abundance will be higher where large carnivores are present, but this prediction assumes limited dietary overlap between large and mesocarnivores. Where dietary overlap is high, e.g., among omnivorous carnivore species, or where prey are relatively easily accessible, the potential exists for large and mesocarnivores to have redundant impacts on prey, though this possibility has not been explored. The intertidal community represents a potentially important but poorly studied resource for coastal carnivore populations, and one …


Immune Profiles Vary Seasonally, But Are Not Significantly Related To Migration Distance Or Natal Dispersal, In A Migratory Songbird, Tosha R. Kelly, Heather L. Macgillivray, Keith A. Hobson, Scott A. Macdougall-Shackleton, Elizabeth A. Macdougall-Shackleton Jan 2017

Immune Profiles Vary Seasonally, But Are Not Significantly Related To Migration Distance Or Natal Dispersal, In A Migratory Songbird, Tosha R. Kelly, Heather L. Macgillivray, Keith A. Hobson, Scott A. Macdougall-Shackleton, Elizabeth A. Macdougall-Shackleton

Biology Publications

A central tenet of ecoimmunology is that an organism’s environment shapes its optimal investment in immunity. For example, the benefits of acquired (relatively pathogen-specific) versus innate (non-specific) immune defences are thought to vary with the risk of encountering familiar versus unfamiliar pathogens. Because pathogen communities vary geographically, individuals that travel farther during seasonal migration or natal dispersal are predicted to have higher exposure to novel pathogens, and lower exposure to familiar pathogens, potentially favoring investment in innate immunity. During the breeding season, migratory animals’ exposure to familiar pathogens should increase, potentially favoring investment in acquired immunity. We hypothesized that song …


Does Cold Activate The Drosophila Melanogaster Immune System?, Golnaz Salehipour-Shirazi, Laura V Ferguson, Brent J Sinclair Jan 2017

Does Cold Activate The Drosophila Melanogaster Immune System?, Golnaz Salehipour-Shirazi, Laura V Ferguson, Brent J Sinclair

Biology Publications

Cold exposure appears to activate aspects of the insect immune system; however, the functional significance of the relationship between cold and immunity is unclear. Insect success at low temperatures is shaped in part by interactions with biotic stressors, such as pathogens, thus it is important to understand how and why immunity might be activated by cold. Here we explore which components of the immune system are activated, and whether those components differ among different kinds of cold exposure. We exposed Drosophila melanogaster to both acute (2h, -2°C) and sustained (10h, -0.5°C) cold, and measured potential (antimicrobial peptide expression, phenoloxidase activity, …


Cold Tolerance Of Third-Instar Drosophila Suzukii Larvae., Ruth Jakobs, Banafsheh Ahmadi, Sarah Houben, Tara D Gariepy, Brent J Sinclair Jan 2017

Cold Tolerance Of Third-Instar Drosophila Suzukii Larvae., Ruth Jakobs, Banafsheh Ahmadi, Sarah Houben, Tara D Gariepy, Brent J Sinclair

Biology Publications

Drosophila suzukii is an emerging global pest of soft fruit; although it likely overwinters as an adult, larval cold tolerance is important both for determining performance during spring and autumn, and for the development of temperature-based control methods aimed at larvae. We examined the low temperature biology of third instar feeding and wandering larvae in and out of food. We induced phenotypic plasticity of thermal biology by rearing under short days and fluctuating temperatures (5.5-19°C). Rearing under fluctuating temperatures led to much slower development (42.1days egg-adult) compared to control conditions (constant 21.5°C; 15.7days), and yielded larger adults of both sexes. …


Freeze Tolerance Of Cyphoderris Monstrosa (Orthoptera: Prophalangopsidae), Jantina Toxopeus, Jacqueline Lebenzon, Alexander H. Mckinnon, Brent J. Sinclair Dec 2016

Freeze Tolerance Of Cyphoderris Monstrosa (Orthoptera: Prophalangopsidae), Jantina Toxopeus, Jacqueline Lebenzon, Alexander H. Mckinnon, Brent J. Sinclair

Biology Publications

The great grig, Cyphoderris monstrosa Uhler (Orthoptera: Prophalangopsidae), is a large (20-30 mm, >1 g), nocturnal ensiferan that in habits montane coniferous forests in northwestern North America. C. monstrosa overwinters as a late-instar nymph, but its cold tolerance strategy has not previously been reported. We collected nymphs from near Kamloops, British Columbia, in late spring to determine their cold tolerance strategy. C. monstrosa nymphs were active at low temperatures until they froze at -4.6 ± 0.3 °C. The nymphs survived internal ice formation (i.e. are freeze tolerant), had a lethal temperature between -9 and -12 °C, and could survive for …


Winter Warming Effects On Overwinter Survival, Energy Use, And Spring Emergence Of Cerotoma Trifurcata (Coleoptera: Chrysomelidae), Emily A. Berzitis, Heather A. Hager, Brent J Sinclair, Rebecca H. Hallett, Jonathan A. Newman Oct 2016

Winter Warming Effects On Overwinter Survival, Energy Use, And Spring Emergence Of Cerotoma Trifurcata (Coleoptera: Chrysomelidae), Emily A. Berzitis, Heather A. Hager, Brent J Sinclair, Rebecca H. Hallett, Jonathan A. Newman

Biology Publications

  1. Bean leaf beetle Cerotoma trifurcata (Förster) (Coleoptera: Chrysomelidae) is a pest of soybean in the U.S.A. and is becoming a concern in Canada. The projected increase in winter temperatures under climate change could affect overwinter survival, timing of spring emergence and, ultimately, the severity of this pest.
  2. We assessed the potential effects of warmer winters in field experiments performed in three consecutive years. Three warming levels were applied: (i) heated approximately 4 °C above ambient; (ii) unheated with snow cover left intact; and (iii) unheated with snow cover removed. Survival and date of emergence were assessed in all years, and …


Ion And Water Balance In Gryllus Crickets During The First Twelve Hours Of Cold Exposure., Lauren E Des Marteaux, Brent J Sinclair Jun 2016

Ion And Water Balance In Gryllus Crickets During The First Twelve Hours Of Cold Exposure., Lauren E Des Marteaux, Brent J Sinclair

Biology Publications

Insects lose ion and water balance during chilling, but the mechanisms underlying this phenomenon are based on patterns of ion and water balance observed in the later stages of cold exposure (12 or more hours). Here we quantified the distribution of ions and water in the hemolymph, muscle, and gut in adult Gryllus field crickets during the first 12h of cold exposure to test mechanistic hypotheses about why homeostasis is lost in the cold, and how chill-tolerant insects might maintain homeostasis to lower temperatures. Unlike in later chill coma, hemolymph [Na(+)] and Na(+) content in the first few hours of …


Reproductive Arrest And Stress Resistance In Winter-Acclimated Drosophila Suzukii., Jantina Toxopeus, Ruth Jakobs, Laura V Ferguson, Tara D Gariepy, Brent J Sinclair Jun 2016

Reproductive Arrest And Stress Resistance In Winter-Acclimated Drosophila Suzukii., Jantina Toxopeus, Ruth Jakobs, Laura V Ferguson, Tara D Gariepy, Brent J Sinclair

Biology Publications

Overwintering insects must survive the multiple-stress environment of winter, which includes low temperatures, reduced food and water availability, and cold-active pathogens. Many insects overwinter in diapause, a developmental arrest associated with high stress tolerance. Drosophila suzukii (Diptera: Drosophilidae), spotted wing drosophila, is an invasive agricultural pest worldwide. Its ability to overwinter and therefore establish in temperate regions could have severe implications for fruit crop industries. We demonstrate here that laboratory populations of Canadian D. suzukii larvae reared under short-day, low temperature, conditions develop into dark 'winter morph' adults similar to those reported globally from field captures, and observed by us …


Possible Radiation-Induced Damage To The Molecular Structure Of Wooden Artifacts Due To Micro-Computed Tomography, Handheld X-Ray Fluorescence, And X-Ray Photoelectron Spectroscopic Techniques, Madalena Kozachuk, Alexandra Suda, Lisa Ellis, Mary Walzak, Mark Biesinger, Sheila Macfie, Robert Hudson, Andrew Nelson, Ronald Martin, Arlen Heginbotham May 2016

Possible Radiation-Induced Damage To The Molecular Structure Of Wooden Artifacts Due To Micro-Computed Tomography, Handheld X-Ray Fluorescence, And X-Ray Photoelectron Spectroscopic Techniques, Madalena Kozachuk, Alexandra Suda, Lisa Ellis, Mary Walzak, Mark Biesinger, Sheila Macfie, Robert Hudson, Andrew Nelson, Ronald Martin, Arlen Heginbotham

Biology Publications

This study was undertaken to ascertain whether radiation produced by X-ray photoelectron spectroscopy (XPS), micro-computed tomography (μCT) and/or portable handheld X-ray fluorescence (XRF) equipment might damage wood artifacts during analysis. Changes at the molecular level were monitored by Fourier transform infrared (FTIR) analysis. No significant changes in FTIR spectra were observed as a result of μCT or handheld XRF analysis. No substantial changes in the collected FTIR spectra were observed when XPS analytical times on the order of minutes were used. However, XPS analysis collected over tens of hours did produce significant changes in the FTIR spectra.