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• 31. [Article] A Study on the Current State of Contaminants of Concern Research, With a Focus on Biosolids and Regulations

  Wastewater treatment plants are a major source of contaminants of emerging concern, as these facilities are the main receptors of these products via household, commercial, and industrial drains, and transport ...

  Citation × Citation Citation Abstract Copy Title: A Study on the Current State of Contaminants of Concern Research, With a Focus on Biosolids and Regulations Author: Fulton, Maren Year: 2016 Wastewater treatment plants are a major source of contaminants of emerging concern, as these facilities are the main receptors of these products via household, commercial, and industrial drains, and transport via stormwater runoff. Biosolids are composed of numerous constituents, with a number of environmentally persistent and potentially toxic contaminants of emerging concern identified as present in large concentrations. Research is needed to understand the transport and fate mechanisms of these compounds in biosolids. Additionally, this research is needed to determine a new priority framework to regulate CECs, both on the national level and regional levels. Wastewater treatment plant influent and effluent treatment regulations and practices may be improved upon as more knowledge accrues regarding contaminants of emerging concern behavior in the environment. The United States environmental regulatory process is a constant work in progress. Inherited from decades-old public health traditions, environmental regulatory programs arose to address the issues of public health as water and air quality issues surfaced. The Toxic Substances Control Act (TSCA) (15 U.S.C. 2601), enacted in 1976, provided the EPA regulatory authority to protect the environment and consumers’ health against risks posed by chemicals in commerce. TSCA only retroactively addressed chemical hazards, after they had been deemed unsafe and previously unrestricted in the public. A bill to overhaul TSCA, the Frank R. Lautenberg Chemical Safety for the 21st Century Act (House Amendment to the Senate Amendment to H.R. 2576, TSCA Modernization Act of 2015), was passed by the Senate on June 7, 2016 and sent on for President Obama’s signature. The amended law will give the EPA new authority to evaluate the safety of a new chemical before it enters the marketplace. It will also allow EPA to evaluate the safety of chemicals already known to be risks, including chemicals found to persist in the human body and in the environment. The Columbia River is presented as a case study as an example of a significant waterbody with research and regulatory gaps concerning CECs. The Columbia River waterbody was chosen as it represents an important natural resource for which data gaps exist on CEC sources and pathways into the waterbody, and which also does not receive adequate protective regulations under the national regulatory framework. Title: A Study on the Current State of Contaminants of Concern Research, With a Focus on Biosolids and Regulations Author: Fulton, Maren Year: 2016 Wastewater treatment plants are a major source of contaminants of emerging concern, as these facilities are the main receptors of these products via household, commercial, and industrial drains, and transport via stormwater runoff. Biosolids are composed of numerous constituents, with a number of environmentally persistent and potentially toxic contaminants of emerging concern identified as present in large concentrations. Research is needed to understand the transport and fate mechanisms of these compounds in biosolids. Additionally, this research is needed to determine a new priority framework to regulate CECs, both on the national level and regional levels. Wastewater treatment plant influent and effluent treatment regulations and practices may be improved upon as more knowledge accrues regarding contaminants of emerging concern behavior in the environment. The United States environmental regulatory process is a constant work in progress. Inherited from decades-old public health traditions, environmental regulatory programs arose to address the issues of public health as water and air quality issues surfaced. The Toxic Substances Control Act (TSCA) (15 U.S.C. 2601), enacted in 1976, provided the EPA regulatory authority to protect the environment and consumers’ health against risks posed by chemicals in commerce. TSCA only retroactively addressed chemical hazards, after they had been deemed unsafe and previously unrestricted in the public. A bill to overhaul TSCA, the Frank R. Lautenberg Chemical Safety for the 21st Century Act (House Amendment to the Senate Amendment to H.R. 2576, TSCA Modernization Act of 2015), was passed by the Senate on June 7, 2016 and sent on for President Obama’s signature. The amended law will give the EPA new authority to evaluate the safety of a new chemical before it enters the marketplace. It will also allow EPA to evaluate the safety of chemicals already known to be risks, including chemicals found to persist in the human body and in the environment. The Columbia River is presented as a case study as an example of a significant waterbody with research and regulatory gaps concerning CECs. The Columbia River waterbody was chosen as it represents an important natural resource for which data gaps exist on CEC sources and pathways into the waterbody, and which also does not receive adequate protective regulations under the national regulatory framework. Close

• 32. [Article] Rolling Circle Mutagenesis of GST-mCherry to Understand Mutation, Gene Expression, and Regulation

  Undergraduates are often familiar with textbook examples of human mutations that affect coding regions and the subsequent disorders, but they may struggle with understanding the implications of mutations ...

  Citation × Citation Citation Abstract Copy Title: Rolling Circle Mutagenesis of GST-mCherry to Understand Mutation, Gene Expression, and Regulation Author: Cole, Jessica, Ferguson, Amanda, Segarra, Verónica A., Walsh, Susan Year: 2017 Undergraduates are often familiar with textbook examples of human mutations that affect coding regions and the subsequent disorders, but they may struggle with understanding the implications of mutations in the regulatory regions of genes. We have designed a laboratory sequence that will allow students to explore the effect random mutagenesis can have on protein function, expression, and ultimately phenotype. Students design and perform a safe and time-efficient random mutagenesis experiment using error-prone rolling circular amplification of a plasmid expressing the inducible fusion protein glutathione S-transferase (GST)-mCherry. Mutagenized and wild-type control plasmid DNA, respectively, are then purified and transformed into bacteria to assess phenotypic changes. While bacteria transformed with the wild type control should be pink, some bacterial colonies transformed with mutagenized plasmids will exhibit a different color. Students attempt to identify their mutations by isolating plasmid from these mutant colonies, sequencing, and comparing their mutant sequence to the wild-type sequence. Additionally, students evaluate the potential effects of mutations on protein production by inducing GST-mCherry expression in cultures, generating cell lysates, and analyzing them using SDS-PAGE. Students who have a phenotypic difference but do not obtain a coding region mutation will be able to think critically about plasmid structure and regulation outside of the gene sequence. Students who do not obtain bacterial transformants have the chance to contemplate how mutation of antibiotic resistance genes or replication origins may have contributed to their results. Overall, this series of laboratories exposes students to basic genetic techniques and helps them conceptualize mutation beyond coding regions. Title: Rolling Circle Mutagenesis of GST-mCherry to Understand Mutation, Gene Expression, and Regulation Author: Cole, Jessica, Ferguson, Amanda, Segarra, Verónica A., Walsh, Susan Year: 2017 Undergraduates are often familiar with textbook examples of human mutations that affect coding regions and the subsequent disorders, but they may struggle with understanding the implications of mutations in the regulatory regions of genes. We have designed a laboratory sequence that will allow students to explore the effect random mutagenesis can have on protein function, expression, and ultimately phenotype. Students design and perform a safe and time-efficient random mutagenesis experiment using error-prone rolling circular amplification of a plasmid expressing the inducible fusion protein glutathione S-transferase (GST)-mCherry. Mutagenized and wild-type control plasmid DNA, respectively, are then purified and transformed into bacteria to assess phenotypic changes. While bacteria transformed with the wild type control should be pink, some bacterial colonies transformed with mutagenized plasmids will exhibit a different color. Students attempt to identify their mutations by isolating plasmid from these mutant colonies, sequencing, and comparing their mutant sequence to the wild-type sequence. Additionally, students evaluate the potential effects of mutations on protein production by inducing GST-mCherry expression in cultures, generating cell lysates, and analyzing them using SDS-PAGE. Students who have a phenotypic difference but do not obtain a coding region mutation will be able to think critically about plasmid structure and regulation outside of the gene sequence. Students who do not obtain bacterial transformants have the chance to contemplate how mutation of antibiotic resistance genes or replication origins may have contributed to their results. Overall, this series of laboratories exposes students to basic genetic techniques and helps them conceptualize mutation beyond coding regions. Close

• 33. [Article] Mechanisms of Animal Diapause: Recent Developments from Nematodes, Crustaceans, Insects, and Fish

  Life cycle delays are beneficial for opportunistic species encountering suboptimal environments. Many animals display a programmed arrest of development (diapause) at some stage(s) of their development, ...

  Citation × Citation Citation Abstract Copy Title: Mechanisms of Animal Diapause: Recent Developments from Nematodes, Crustaceans, Insects, and Fish Author: Hand, Steven C., Denlinger, David L., Podrabsky, Jason E., Roy, Richard Year: 2016 Life cycle delays are beneficial for opportunistic species encountering suboptimal environments. Many animals display a programmed arrest of development (diapause) at some stage(s) of their development, and the diapause state may or may not be associated with some degree of metabolic depression. In this review, we will evaluate current advancements in our understanding of the mechanisms responsible for the remarkable phenotype, as well as environmental cues that signal entry and termination of the state. The developmental stage at which diapause occurs dictates and constrains the mechanisms governing diapause. Considerable progress has been made in clarifying proximal mechanisms of metabolic arrest and the signaling pathways like insulin/Foxo that control gene expression patterns. Overlapping themes are also seen in mechanisms that control cell cycle arrest. Evidence is emerging for epigenetic contributions to diapause regulation via small RNAs in nematodes, crustaceans, insects, and fish. Knockdown of circadian clock genes in selected insect species supports the importance of clock genes in the photoperiodic response that cues diapause. A large suite of chaperone-like proteins, expressed during diapause, protects biological structures during long periods of energy-limited stasis. More information is needed to paint a complete picture of how environmental cues are coupled to the signal transduction that initiates the complex diapause phenotype, as well as molecular explanations for how the state is terminated. Excellent examples of molecular memory in post-dauer animals have been documented in Caenorhabditis elegans It is clear that a single suite of mechanisms does not regulate diapause across all species and developmental stages. Title: Mechanisms of Animal Diapause: Recent Developments from Nematodes, Crustaceans, Insects, and Fish Author: Hand, Steven C., Denlinger, David L., Podrabsky, Jason E., Roy, Richard Year: 2016 Life cycle delays are beneficial for opportunistic species encountering suboptimal environments. Many animals display a programmed arrest of development (diapause) at some stage(s) of their development, and the diapause state may or may not be associated with some degree of metabolic depression. In this review, we will evaluate current advancements in our understanding of the mechanisms responsible for the remarkable phenotype, as well as environmental cues that signal entry and termination of the state. The developmental stage at which diapause occurs dictates and constrains the mechanisms governing diapause. Considerable progress has been made in clarifying proximal mechanisms of metabolic arrest and the signaling pathways like insulin/Foxo that control gene expression patterns. Overlapping themes are also seen in mechanisms that control cell cycle arrest. Evidence is emerging for epigenetic contributions to diapause regulation via small RNAs in nematodes, crustaceans, insects, and fish. Knockdown of circadian clock genes in selected insect species supports the importance of clock genes in the photoperiodic response that cues diapause. A large suite of chaperone-like proteins, expressed during diapause, protects biological structures during long periods of energy-limited stasis. More information is needed to paint a complete picture of how environmental cues are coupled to the signal transduction that initiates the complex diapause phenotype, as well as molecular explanations for how the state is terminated. Excellent examples of molecular memory in post-dauer animals have been documented in Caenorhabditis elegans It is clear that a single suite of mechanisms does not regulate diapause across all species and developmental stages. Close

• 34. [Article] Allosteric Mechanism of Water Channel Gating by Ca2+–calmodulin

  Calmodulin (CaM) is a universal regulatory protein that communicates the presence of calcium to its molecular targets and correspondingly modulates their function. This key signaling protein is important ...

  Citation × Citation Citation Abstract Copy Title: Allosteric Mechanism of Water Channel Gating by Ca2+–calmodulin Author: Reichow, Steve, Clemens, Daniel M., Freites, J. Alfredo, Németh-Cahalan, Karin L., Heyden, Matthias, Tobias, Douglas J., Hall, James E., Gonen, Tamir Year: 2013 Calmodulin (CaM) is a universal regulatory protein that communicates the presence of calcium to its molecular targets and correspondingly modulates their function. This key signaling protein is important for controlling the activity of hundreds of membrane channels and transporters. However, our understanding of the structural mechanisms driving CaM regulation of full-length membrane proteins has remained elusive. In this study, we determined the pseudo-atomic structure of full-length mammalian aquaporin-0 (AQP0, Bos Taurus) in complex with CaM using electron microscopy to understand how this signaling protein modulates water channel function. Molecular dynamics and functional mutation studies reveal how CaM binding inhibits AQP0 water permeability by allosterically closing the cytoplasmic gate of AQP0. Our mechanistic model provides new insight, only possible in the context of the fully assembled channel, into how CaM regulates multimeric channels by facilitating cooperativity between adjacent subunits. Title: Allosteric Mechanism of Water Channel Gating by Ca2+–calmodulin Author: Reichow, Steve, Clemens, Daniel M., Freites, J. Alfredo, Németh-Cahalan, Karin L., Heyden, Matthias, Tobias, Douglas J., Hall, James E., Gonen, Tamir Year: 2013 Calmodulin (CaM) is a universal regulatory protein that communicates the presence of calcium to its molecular targets and correspondingly modulates their function. This key signaling protein is important for controlling the activity of hundreds of membrane channels and transporters. However, our understanding of the structural mechanisms driving CaM regulation of full-length membrane proteins has remained elusive. In this study, we determined the pseudo-atomic structure of full-length mammalian aquaporin-0 (AQP0, Bos Taurus) in complex with CaM using electron microscopy to understand how this signaling protein modulates water channel function. Molecular dynamics and functional mutation studies reveal how CaM binding inhibits AQP0 water permeability by allosterically closing the cytoplasmic gate of AQP0. Our mechanistic model provides new insight, only possible in the context of the fully assembled channel, into how CaM regulates multimeric channels by facilitating cooperativity between adjacent subunits. Close

• 35. [Article] Coxiella burnetii and Leishmania Mexicana Residing Within Similar Parasitophorous Vacuoles Elicit Disparate Host Responses

  Coxiella burnetii is a bacterium that thrives in an acidic parasitophorous vacuole (PV) derived from lysosomes. Leishmania mexicana, a eukaryote, has also independently evolved to live in a morphologically ...

  Citation × Citation Citation Abstract Copy Title: Coxiella burnetii and Leishmania Mexicana Residing Within Similar Parasitophorous Vacuoles Elicit Disparate Host Responses Author: Millar, Jess A., Valdés, Raquel, Kacharia, Fenil, Landfear, Scott M., Cambronne, Eric D., Raghavan, Rahul, Soong, Lynn, Malchiodi, Emilio Luis Year: 2015 Coxiella burnetii is a bacterium that thrives in an acidic parasitophorous vacuole (PV) derived from lysosomes. Leishmania mexicana, a eukaryote, has also independently evolved to live in a morphologically similar PV. As Coxiella and Leishmania are highly divergent organisms that cause different diseases, we reasoned that their respective infections would likely elicit distinct host responses despite producing phenotypically similar parasite-containing vacuoles. The objective of this study was to investigate, at the molecular level, the macrophage response to each pathogen. Infection of THP-1 (human monocyte/macrophage) cells with Coxiella and Leishmania elicited disparate host responses. At 5 days post-infection, when compared to uninfected cells, 1057 genes were differentially expressed (746 genes up-regulated and 311 genes downregulated) in C. burnetii infected cells, whereas 698 genes (534 genes up-regulated and 164 genes down-regulated) were differentially expressed in L. mexicana infected cells. Interestingly, of the 1755 differentially expressed genes identified in this study, only 126 genes (∼7%) are common to both infections. We also discovered that 1090 genes produced mRNA isoforms at significantly different levels under the two infection conditions, suggesting that alternate proteins encoded by the same gene might have important roles in host response to each infection. Additionally, we detected 257 micro RNAs (miRNAs) that were expressed in THP-1 cells, and identified miRNAs that were specifically expressed during Coxiella or Leishmania infections. Collectively, this study identified host mRNAs and miRNAs that were influenced by Coxiella and/or Leishmania infections, and our data indicate that although their PVs are morphologically similar, Coxiella and Leishmania have evolved different strategies that perturb distinct host processes to create and thrive within their respective intracellular niches. Title: Coxiella burnetii and Leishmania Mexicana Residing Within Similar Parasitophorous Vacuoles Elicit Disparate Host Responses Author: Millar, Jess A., Valdés, Raquel, Kacharia, Fenil, Landfear, Scott M., Cambronne, Eric D., Raghavan, Rahul, Soong, Lynn, Malchiodi, Emilio Luis Year: 2015 Coxiella burnetii is a bacterium that thrives in an acidic parasitophorous vacuole (PV) derived from lysosomes. Leishmania mexicana, a eukaryote, has also independently evolved to live in a morphologically similar PV. As Coxiella and Leishmania are highly divergent organisms that cause different diseases, we reasoned that their respective infections would likely elicit distinct host responses despite producing phenotypically similar parasite-containing vacuoles. The objective of this study was to investigate, at the molecular level, the macrophage response to each pathogen. Infection of THP-1 (human monocyte/macrophage) cells with Coxiella and Leishmania elicited disparate host responses. At 5 days post-infection, when compared to uninfected cells, 1057 genes were differentially expressed (746 genes up-regulated and 311 genes downregulated) in C. burnetii infected cells, whereas 698 genes (534 genes up-regulated and 164 genes down-regulated) were differentially expressed in L. mexicana infected cells. Interestingly, of the 1755 differentially expressed genes identified in this study, only 126 genes (∼7%) are common to both infections. We also discovered that 1090 genes produced mRNA isoforms at significantly different levels under the two infection conditions, suggesting that alternate proteins encoded by the same gene might have important roles in host response to each infection. Additionally, we detected 257 micro RNAs (miRNAs) that were expressed in THP-1 cells, and identified miRNAs that were specifically expressed during Coxiella or Leishmania infections. Collectively, this study identified host mRNAs and miRNAs that were influenced by Coxiella and/or Leishmania infections, and our data indicate that although their PVs are morphologically similar, Coxiella and Leishmania have evolved different strategies that perturb distinct host processes to create and thrive within their respective intracellular niches. Close

• 36. [Article] Regulations of E-Bikes in North America

  Throughout the world, the electric bicycle (e-bike) industry is growing very quickly. The North American market has been somewhat slow to adopt this technology, which is still considered to be in the “early ...

  Citation × Citation Citation Abstract Copy Title: Regulations of E-Bikes in North America Author: MacArthur, John, Kobel, Nicholas Year: 2014 Throughout the world, the electric bicycle (e-bike) industry is growing very quickly. The North American market has been somewhat slow to adopt this technology, which is still considered to be in the “early adopter” phase (Rose & Dill, 2011; Rose, 2011), but in recent years, this has begun to change. But as e-bike numbers increase, so too will potential conflicts (actual or perceived) with other vehicles and non-motorized devices, bicycles and pedestrians, causing policy questions to arise. Indeed, conflicting user groups are petitioning state legislatures and local governments for permission to operate legally on roadways and paths or to ban these devices. Although some states, such as Oregon, Minnesota, and Pennsylvania, have created specific e-bike legislation, other states’ legislation surrounding e-bikes is best described as nebulous. The confusion stems from the wide variety of devices and technologies on the market; perceived overlap of legal entities' jurisdiction over the device, which under certain circumstances can be either a consumer product or a motor vehicle; outdated laws and regulations; and inconsistency of terms. The purpose of this paper is to outline the different classifications of ebikes—what they are and what they are not—and to help shed light on aspects of federal and state legislation of e-bikes. In addition, this paper explores the potential conflicts these regulations may cause for the adoption of this technology. Title: Regulations of E-Bikes in North America Author: MacArthur, John, Kobel, Nicholas Year: 2014 Throughout the world, the electric bicycle (e-bike) industry is growing very quickly. The North American market has been somewhat slow to adopt this technology, which is still considered to be in the “early adopter” phase (Rose & Dill, 2011; Rose, 2011), but in recent years, this has begun to change. But as e-bike numbers increase, so too will potential conflicts (actual or perceived) with other vehicles and non-motorized devices, bicycles and pedestrians, causing policy questions to arise. Indeed, conflicting user groups are petitioning state legislatures and local governments for permission to operate legally on roadways and paths or to ban these devices. Although some states, such as Oregon, Minnesota, and Pennsylvania, have created specific e-bike legislation, other states’ legislation surrounding e-bikes is best described as nebulous. The confusion stems from the wide variety of devices and technologies on the market; perceived overlap of legal entities' jurisdiction over the device, which under certain circumstances can be either a consumer product or a motor vehicle; outdated laws and regulations; and inconsistency of terms. The purpose of this paper is to outline the different classifications of ebikes—what they are and what they are not—and to help shed light on aspects of federal and state legislation of e-bikes. In addition, this paper explores the potential conflicts these regulations may cause for the adoption of this technology. Close

• 37. [Article] Transcriptomic Analysis of Maternally Provisioned Cues for Phenotypic Plasticity in the Annual Killifish, <i>Austrofundulus limnaeus</i>

  Background: Genotype and environment can interact during development to produce novel adaptive traits that support life in extreme conditions. The development of the annual killifsh Austrofundulus limnaeus ...

  Citation × Citation Citation Abstract Copy Title: Transcriptomic Analysis of Maternally Provisioned Cues for Phenotypic Plasticity in the Annual Killifish, <i>Austrofundulus limnaeus</i> Author: Romney, Amie L., Podrabsky, Jason E. Year: 2017 Background: Genotype and environment can interact during development to produce novel adaptive traits that support life in extreme conditions. The development of the annual killifsh Austrofundulus limnaeus is unique among vertebrates because the embryos have distinct cell movements that separate epiboly from axis formation during early development, can enter into a state of metabolic dormancy known as diapause and can survive extreme environmental conditions. The ability to enter into diapause can be maternally programmed, with young females producing embryos that do not enter into diapause. Alternately, embryos can be programmed to “escape” from diapause and develop directly by both maternal factors and embryonic incubation conditions. Thus, maternally packaged gene products are hypothesized to regulate developmental trajectory and perhaps the other unique developmental characters in this species. Results: Using high-throughput RNA sequencing, we generated transcriptomic profles of mRNAs, long non-coding RNAs and small non-coding RNAs (sncRNAs) in 1–2 cell stage embryos of A. limnaeus. Transcriptomic analyses suggest maternal programming of embryos through alternatively spliced mRNAs and antisense sncRNAs. Comparison of these results to those of comparable studies on zebrafsh and other fshes reveals a surprisingly high abundance of transcripts involved in the cellular response to stress and a relatively lower expression of genes required for rapid transition through the cell cycle. Conclusions: Maternal programming of developmental trajectory is unlikely accomplished by diferential expression of diapause-specifc genes. Rather, evidence suggests a role for trajectory-specifc splice variants of genes expressed in both phenotypes. In addition, based on comparative studies with zebrafsh, the A. limnaeus 1–2 cell stage transcriptome is unique in ways that are consistent with their unique life history. These results not only impact our understanding of the genetic mechanisms that regulate entrance into diapause, but also provide insight into the epigenetic regulation of gene expression during development Title: Transcriptomic Analysis of Maternally Provisioned Cues for Phenotypic Plasticity in the Annual Killifish, <i>Austrofundulus limnaeus</i> Author: Romney, Amie L., Podrabsky, Jason E. Year: 2017 Background: Genotype and environment can interact during development to produce novel adaptive traits that support life in extreme conditions. The development of the annual killifsh Austrofundulus limnaeus is unique among vertebrates because the embryos have distinct cell movements that separate epiboly from axis formation during early development, can enter into a state of metabolic dormancy known as diapause and can survive extreme environmental conditions. The ability to enter into diapause can be maternally programmed, with young females producing embryos that do not enter into diapause. Alternately, embryos can be programmed to “escape” from diapause and develop directly by both maternal factors and embryonic incubation conditions. Thus, maternally packaged gene products are hypothesized to regulate developmental trajectory and perhaps the other unique developmental characters in this species. Results: Using high-throughput RNA sequencing, we generated transcriptomic profles of mRNAs, long non-coding RNAs and small non-coding RNAs (sncRNAs) in 1–2 cell stage embryos of A. limnaeus. Transcriptomic analyses suggest maternal programming of embryos through alternatively spliced mRNAs and antisense sncRNAs. Comparison of these results to those of comparable studies on zebrafsh and other fshes reveals a surprisingly high abundance of transcripts involved in the cellular response to stress and a relatively lower expression of genes required for rapid transition through the cell cycle. Conclusions: Maternal programming of developmental trajectory is unlikely accomplished by diferential expression of diapause-specifc genes. Rather, evidence suggests a role for trajectory-specifc splice variants of genes expressed in both phenotypes. In addition, based on comparative studies with zebrafsh, the A. limnaeus 1–2 cell stage transcriptome is unique in ways that are consistent with their unique life history. These results not only impact our understanding of the genetic mechanisms that regulate entrance into diapause, but also provide insight into the epigenetic regulation of gene expression during development Close

• 38. [Article] Associations between the Willingness to Exert Cognitive Effort and Smoking Abstinence

  In decision-making tasks, individuals who prefer smaller, immediate rewards over larger, delayed rewards (delay discounting) are less likely to quit smoking. Indeed, decision-making tasks with delayed ...

  Citation × Citation Citation Abstract Copy Title: Associations between the Willingness to Exert Cognitive Effort and Smoking Abstinence Author: Phanouvong, Austin A. Year: 2017 In decision-making tasks, individuals who prefer smaller, immediate rewards over larger, delayed rewards (delay discounting) are less likely to quit smoking. Indeed, decision-making tasks with delayed reward costs are sensitive to many aspects of substance use disorders. However, other reward costs might also be important. Our study focused on one of these other reward costs, which was cognitive effort (CE). 22 current smokers who were anticipating quitting in the near future were recruited to validate if more CE discounting predicted shorter abstinence times in reinforced smoking lapse period. Each participant had to be over the age of 21, and smoke an average of 10 or more cigarettes daily. Before the smoking lapse period, participants competed a control or regulated ego depletion task, which the regulated version was characterized to lower self-control. It was suspected that participants with larger values of the areas under the curve (AUC) of the CE discounting task would have shorter abstinence times. It would be especially true for the individuals that had self-control lowered by the regulated version of the ego-depletion task. The results show that there was no correlation between the CE discounting task and abstinence times of the lapse periods, but the experiment shows excellent replicability between the two sessions each participant completed. Authors: Austin A. Phanouvong, Darby K. Dyar, Suzanne H. Mitchell Presenter: Austin A. Phanouvong Title: Associations between the Willingness to Exert Cognitive Effort and Smoking Abstinence Author: Phanouvong, Austin A. Year: 2017 In decision-making tasks, individuals who prefer smaller, immediate rewards over larger, delayed rewards (delay discounting) are less likely to quit smoking. Indeed, decision-making tasks with delayed reward costs are sensitive to many aspects of substance use disorders. However, other reward costs might also be important. Our study focused on one of these other reward costs, which was cognitive effort (CE). 22 current smokers who were anticipating quitting in the near future were recruited to validate if more CE discounting predicted shorter abstinence times in reinforced smoking lapse period. Each participant had to be over the age of 21, and smoke an average of 10 or more cigarettes daily. Before the smoking lapse period, participants competed a control or regulated ego depletion task, which the regulated version was characterized to lower self-control. It was suspected that participants with larger values of the areas under the curve (AUC) of the CE discounting task would have shorter abstinence times. It would be especially true for the individuals that had self-control lowered by the regulated version of the ego-depletion task. The results show that there was no correlation between the CE discounting task and abstinence times of the lapse periods, but the experiment shows excellent replicability between the two sessions each participant completed. Authors: Austin A. Phanouvong, Darby K. Dyar, Suzanne H. Mitchell Presenter: Austin A. Phanouvong Close

• 39. [Article] Insulin-like growth factor signaling regulates developmental trajectory associated with diapause in embryos of the annual killifish Austrofundulus limnaeus

  Annual killifishes exhibit a number of unique life history characters including the occurrence of embryonic diapause, unique cell movements associated with dispersion and subsequent reaggregation of the ...

  Citation × Citation Citation Abstract Copy Title: Insulin-like growth factor signaling regulates developmental trajectory associated with diapause in embryos of the annual killifish Austrofundulus limnaeus Author: Woll, S. Cody, Podrabsky, Jason E. Year: 2017 Annual killifishes exhibit a number of unique life history characters including the occurrence of embryonic diapause, unique cell movements associated with dispersion and subsequent reaggregation of the embryonic blastomeres, and a short postembryonic life span. Insulin-like growth factor (IGF) signaling is known to play a role in the regulation of metabolic dormancy in a number of animals but has not been explored in annual killifishes. The abundance of IGF proteins during development and the developmental effects of blocking IGF signaling by pharmacological inhibition of the insulin-like growth factor I receptor (IGF1R) were explored in embryos of the annual killifish Austrofundulus limnaeus. Blocking of IGF signaling in embryos that would normally escape entrance into diapause resulted in a phenotype that was remarkably similar to that of embryos entering diapause. IGF-I protein abundance spikes during early development in embryos that will not enter diapause. In contrast, IGF-I levels remain low during early development in embryos that will enter diapause II. IGF-II protein is packaged at higher levels in escape-bound embryos compared with diapause-bound embryos. However, IGF-II levels quickly decrease and remain low during early development and only increase substantially during late development in both developmental trajectories. Developmental patterns of IGF-I and IGF-II protein abundance under conditions that would either induce or bypass entrance into diapause are consistent with a role for IGF signaling in the regulation of developmental trajectory and entrance into diapause in this species. We propose that IGF signaling may be a unifying regulatory pathway that explains the larger suite of characters that are associated with the complex life history of annual killifishes. Title: Insulin-like growth factor signaling regulates developmental trajectory associated with diapause in embryos of the annual killifish Austrofundulus limnaeus Author: Woll, S. Cody, Podrabsky, Jason E. Year: 2017 Annual killifishes exhibit a number of unique life history characters including the occurrence of embryonic diapause, unique cell movements associated with dispersion and subsequent reaggregation of the embryonic blastomeres, and a short postembryonic life span. Insulin-like growth factor (IGF) signaling is known to play a role in the regulation of metabolic dormancy in a number of animals but has not been explored in annual killifishes. The abundance of IGF proteins during development and the developmental effects of blocking IGF signaling by pharmacological inhibition of the insulin-like growth factor I receptor (IGF1R) were explored in embryos of the annual killifish Austrofundulus limnaeus. Blocking of IGF signaling in embryos that would normally escape entrance into diapause resulted in a phenotype that was remarkably similar to that of embryos entering diapause. IGF-I protein abundance spikes during early development in embryos that will not enter diapause. In contrast, IGF-I levels remain low during early development in embryos that will enter diapause II. IGF-II protein is packaged at higher levels in escape-bound embryos compared with diapause-bound embryos. However, IGF-II levels quickly decrease and remain low during early development and only increase substantially during late development in both developmental trajectories. Developmental patterns of IGF-I and IGF-II protein abundance under conditions that would either induce or bypass entrance into diapause are consistent with a role for IGF signaling in the regulation of developmental trajectory and entrance into diapause in this species. We propose that IGF signaling may be a unifying regulatory pathway that explains the larger suite of characters that are associated with the complex life history of annual killifishes. Close

• 40. [Article] Epigenetic Regulation of Alternative Developmental Trajectories

  The annual killifish, Austrofundulus limnaeus, is capable of entering into a state of metabolic and developmental dormancy during embryogenesis termed diapause. However, individuals may also follow an ...

  Citation × Citation Citation Abstract Copy Title: Epigenetic Regulation of Alternative Developmental Trajectories Author: Romney, Arnie Lynn T., Podrabsky, Jason E. Year: 2017 The annual killifish, Austrofundulus limnaeus, is capable of entering into a state of metabolic and developmental dormancy during embryogenesis termed diapause. However, individuals may also follow an alternative phenotypic trajectory and instead "escaped" entry into diapause and develop continuously until hatching. Early development along the two trajectories is morphologically indistinguishable, and gene regulatory mechanisms are currently unknown. Phenotype appears to be influenced by maternal provisioning based on the observation that young females produce predominately escape embryos and older females produce diapausing embryos. Additionally, the incubation temperature of embryos can override this maternal pattern and alter trajectory. Maternal provisioning is known in many vertebrates to direct early development prior to the initiation of embryonic gene transcription. Using RNA-seq, we have generated transcriptomic profiles of messenger RNAs (mRNAs) during embryogenesis of A. limnaeus. Embryos that are destined for either the diapause or escape phenotypes have unique profiles of mRNA isoforms at fertilization; well before they are morphologically distinct. We hypothesize that maternally packaged gene products coordinate the cellular events that determine developmental trajectory in A. limnaeus. In addition, we propose the expression of environmentally responsive microRNAs during development that can override maternal provisioning. RNA-seq data during early development, after the maternal-to-zygotic transition, suggest distinct profiles of microRNA expression that are phenotype specific. Our findings suggest maternal programming of diapause through the packaging of specific mRNAs as well as temperature induced microRNAs that target maternal transcripts allowing an escape from the diapause trajectory. This presents a novel example of maternal-embryonic-conflict in gene regulation that provides the embryo with alternatives in developmental trajectories in the face of fluctuating environmental patterns. These results will not only impact our understanding of genetic mechanisms that regulate entrance into diapause, but will also provide insight into epigenetic control of development. Title: Epigenetic Regulation of Alternative Developmental Trajectories Author: Romney, Arnie Lynn T., Podrabsky, Jason E. Year: 2017 The annual killifish, Austrofundulus limnaeus, is capable of entering into a state of metabolic and developmental dormancy during embryogenesis termed diapause. However, individuals may also follow an alternative phenotypic trajectory and instead "escaped" entry into diapause and develop continuously until hatching. Early development along the two trajectories is morphologically indistinguishable, and gene regulatory mechanisms are currently unknown. Phenotype appears to be influenced by maternal provisioning based on the observation that young females produce predominately escape embryos and older females produce diapausing embryos. Additionally, the incubation temperature of embryos can override this maternal pattern and alter trajectory. Maternal provisioning is known in many vertebrates to direct early development prior to the initiation of embryonic gene transcription. Using RNA-seq, we have generated transcriptomic profiles of messenger RNAs (mRNAs) during embryogenesis of A. limnaeus. Embryos that are destined for either the diapause or escape phenotypes have unique profiles of mRNA isoforms at fertilization; well before they are morphologically distinct. We hypothesize that maternally packaged gene products coordinate the cellular events that determine developmental trajectory in A. limnaeus. In addition, we propose the expression of environmentally responsive microRNAs during development that can override maternal provisioning. RNA-seq data during early development, after the maternal-to-zygotic transition, suggest distinct profiles of microRNA expression that are phenotype specific. Our findings suggest maternal programming of diapause through the packaging of specific mRNAs as well as temperature induced microRNAs that target maternal transcripts allowing an escape from the diapause trajectory. This presents a novel example of maternal-embryonic-conflict in gene regulation that provides the embryo with alternatives in developmental trajectories in the face of fluctuating environmental patterns. These results will not only impact our understanding of genetic mechanisms that regulate entrance into diapause, but will also provide insight into epigenetic control of development. Close