bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acute Hypoxia Alters Ryanodine Receptor Activity in Pulmonary Arterial Myocytes of High Altitude Acclimatized Fetal and Adult Sheep
Authors: Thomas Jonathan , Yoo Timothy , Romero Monica , Puglisi Jose , Zhang Lubo , Wilson Sean M. 
Published: June 2021

Intrauterine stress, such as long term high altitude hypoxia (LTH), can alter pulmonary function and reprogram fetal pulmonary vascular development, potentially causing respiratory distress and pulmonary hypertension after birth. Our recent data demonstrates that newborn LTH lambs exhibit exaggerated hypoxia‐induced pulmonary vasoconstriction (HPV). Previous evidence shows Ryanodine Receptor (RyR) activation is central to the HPV response. Furthermore, LTH disrupts RyR activated Ca2+ sparks in pulmonary arterial (PA) myocytes of sheep. Given the relationship between RyR and HPV responses, we tested the hypothesis that acute hypoxia (exposure to 4% O2) and LTH increase RyR mediated Ca2+ spark activity. This was tested by measuring the Ca2+ spark activity in PA myocytes of near‐term fetal lambs and adult sheep that resided at either low (335m, LA) or high (3801m, HA) altitude. Intracellular Ca2+ was recorded in myocytes of isolated PA tissues loaded with Fluo‐4 using line‐scan techniques on a confocal microscope. Line‐scan images were analyzed using custom software (SparkLab) to determine the number of cells displaying sparks, spark frequency, and spatial‐ temporal characteristics. Adult myocytes had greater prevalence and frequency of Ca2+ sparks relative to those of fetuses, confirming previous studies. Acute hypoxia significantly decreased spark prevalence and frequency in myocytes from both HA fetal and LA adult groups; however, acute hypoxia increased spark prevalence and frequency in HA adult sheep. Spark amplitude was decreased by acute hypoxia in the LA fetus but increased in the HA adult. Acute hypoxia also reduced spark duration in the fetus independent of altitude but increased the duration in HA adult. These results provide new insight into the influence of high altitude reprogramming of RyR function in PA of the fetus and adult and the roles their activity have during acute hypoxic exposures.Support or Funding InformationThis work is supported by The National Institutes of Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development grant number HD083132, by the National Science Foundation under Grant No. MRI 0923559, and the Loma Linda University School of Medicine. JT was a Loma Linda University Summer Undergraduate Research Fellow while TY was a Walter E Macpherson Society Medical Student Summer Research Fellow.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Cyclic Nucleotides Reduce Ryanodine Receptor Mediated Ca2+ Spark Activation Independent of Long Term Hypoxia in Ovine Fetal Pulmonary Arterial Myocytes
Authors: Guerrero Maria , Hough Steven , Romero Monica , Puglisi Jose , Zhang Lubo , Wilson Sean M. 
Published: June 2021

Ryanodine receptors (RyR) release Ca2+ from smooth muscle sarcoplasmic reticulum in rapid events known as Ca2+ sparks. These Ca2+ sparks activate voltage and Ca2+ gated potassium channels (BK channels) that cause cell repolarization. Ca2+ spark‐BK channel mediated cell repolarization dilates many types of vessels and is essential to pulmonary arterial (PA) vasodilation during the fetal transition to breathing air. Infants who do not successfully negotiate this transition are at risk of developing pulmonary hypertension, which has significant morbidity and mortality. Previous work shows that long term hypoxia (LTH) decreases Ca2+ spark events in fetal pulmonary arterial smooth muscle cells (PASMCs) even though the Ca2+ stores have functional RyRs. Additional studies illustrate that cyclic nucleotides can increase RyR activity, which led us to test the hypothesis that cyclic nucleotides could rescue RyR activity in myocytes of LTH fetuses. This was examined by treating PAs isolated from low (700m; LA) and high altitude (3801m; HA) near‐term fetal sheep with exogenous cyclic AMP (cAMP) and cyclic GMP (cGMP) or the methylxanthine IBMX, a non‐specific cAMP and cGMP phosphodiesterase inhibitor. RyR activity was measured by confocal imaging of Ca2+ sparks in fluo‐4 labeled PASMCs. The spatial and temporal aspects to the Ca2+ sparks were evaluated using SparkLab, a custom software package. Contrary to our hypothesis, the prevalence of Ca2+ sparks decreased in the presence of cAMP, cGMP, and IBMX for PASMC from both LA and HA fetal sheep. These data suggest that cyclic nucleotides reduce instead of increase vasodilatory capacity via RyR‐BK channel coupling mechanisms. Furthermore, increased cyclic nucleotides had no effect on the spatial‐temporal aspects to the Ca2+ sparks. Even though the signaling pathway remains unclear, the reduction of Ca2+ sparks by cyclic nucleotides is potentially a novel mechanism of RyR modulation in sheep fetal PASMC. This data suggests that increasing cyclic nucleotides may be contra‐indicated in newborn infants who are at risk of developing pulmonary hypertension.Support or Funding InformationThis work is supported by The National Institutes of Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development grant number HD083132, by the National Science Foundation under Grant No. MRI 0923559, and the Loma Linda University School of Medicine. SH was a Loma Linda University Summer Undergraduate Research Fellow.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Effects Of Ethynylestradiol‐3‐Sulfate (EE‐3‐S) On Blood Volume and Organ Function In Pigs With Severe Traumatic Hemorrhage
Authors: Martini Wenjun Z. , Xia Hui , Dubick Michael A. 
Published: June 2021

IntroductionThe beneficial effects of estrogens to improve survival from hemorrhage have been suggested in experimental studies of rodents and minipigs, as well as some clinical observations. However, the underlying possible protective mechanisms remain unclear. This study investigated the effects of ethynylestradiol‐3‐sulfate (EE‐3‐S) on blood volume and organ functions in pigs following severe traumatic hemorrhage and hypotensive resuscitation.MethodsTwenty anesthetized and instrumented pigs were randomized into saline (n=10) and EE‐3‐S(n=10) groups. Femur fracture was performed in each pig's left leg, followed byhemorrhage of 55% of estimated blood volume and 15 min shock period. Afterwards, pigs were hypotensively resuscitated with a small volume of saline(4 ml/kg) or EE‐3‐S (1 mg/kg at concentration of 1 mg/ml, plus 3 ml saline/kg). Indocyanine green dye (5 ml of 1 mg/ml) was injected before femur fracture and hemorrhage and 15 min after EE‐3‐S administration with serial blood samples taken accordingly to determine changes of blood volume. Pigs remained anesthetized and were monitored for 6 h or until death, and blood samples were taken every 2 h for measurements of blood gases and chemistry.ResultsAll baseline measurements are similar between the two groups. Femur fracture and hemorrhage reduced mean arterial pressure to 54±6% of baseline values and reduced blood volume from 104±4 ml/kg to 67±4 ml/kg (both p<0.05) and reduced Hctfrom 31±1% to 28±1% in the saline resuscitated group. Similar reductions were observed with EE‐3‐S resuscitation in blood volume (from 109±4 ml/kg to 68±3 ml/kg, p<0.05) and Hct (30±1% to 27±1%, p<0.05). Compared to baseline value, creatinine, asparate aminotransferase (AST), and lactate dehydrogenase(LDH) were elevated at 6 h or death from 1.3±0.1 mg/dL to 3.1± 0.2 mg/dL, 33±3 U/L to 98±16 U/L, and 450± 55 U/L to 645±122 U/L, respectively (all p<0.05). Similar increases were observed in creatinine (1.4±0.2 mg/dL to 2.9±0.1 mg/dL), AST (32±3 U/L to 135±46 U/L) and LDH (450±35 U/L to 501±95 U/L) in the EE‐3‐S group (all p<0.05). Survival time was similar between the saline (212±43 min) and EE‐3‐S (212±39 min) groups.ConclusionsFollowing severe traumatic hemorrhage and small volume resuscitation, administration of EE‐3‐S did not affect blood volume, organ function or short term survival in this model.Support or Funding InformationUS Army Medical Research and Materiel CommandThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
SYP73 Is a Novel Membrane‐Associated Actin‐Binding Protein that Anchors the ER to the Actin Cytoskeleton in Arabidopsis
Authors: Cao Pengfei , Renna Luciana , Stefano Giovanni , Brandizzi Federica 
Published: June 2021

The endoplasmic reticulum (ER) is an essential organelle that spreads throughout the cytoplasm and undergoes extensive remodeling. In plants, the remodeling and motility of the ER rely mainly on actin and to a minor extent on microtubules. Although the actomyosin system has been suggested functional for ER streaming in plant cells, the mechanisms underlying stable interaction of the ER membrane with actin are unknown. We demonstrate that SYP73, a member of the plant Syp7 subgroup of SNARE proteins is a novel ER membrane‐associated actin‐binding protein. We show that overexpression of SYP73 causes a striking rearrangement of the ER over actin and that loss of SYP73 reduces ER streaming and affects overall ER network morphology and plant growth. A potential mechanism that regulates SYP73 functions has been investigated. Although conserved domain prediction tools did not detect any actin‐binding domain in SYP73, we identified a fragment that is mainly responsible for SYP73 actin binding. Furthermore, the role of SYP73 in regulating actin reorganization has also been examined. We propose a model for plant ER remodeling whereby the dynamic rearrangement and streaming of the ER network depend on the propelling action of myosin‐XI over actin coupled with a SYP73‐mediated bridging, which dynamically anchors the ER membrane with actin filaments.Support or Funding InformationThis work is support by the Chemical Sciences, Geosciences and Biosciences Division, Office of Basic Energy Sciences, Office of Science, US Department of Energy, the National Science Foundation, and MSU AgBioResearch.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Investigation of Cellular Hyperosmotic Stress Response Pathways using CRISPR in Fishes
Authors: Hamar Jens Carlton , Kültz Dietmar 
Published: June 2021

Osmotic stress is one of the primary challenges faced by aquatic animals and their capacity to osmoregulate in response will dictate its survivability within a given set of conditions. The life history of many fish species includes periods of hyperosmotic stress. Two primary physiological responses a fish can employ to these conditions are systemic, attempting to maintain internal osmotic homeostasis, or cellular by adjusting the intracellular environment to the new osmotic gradient. Cell cultures can serve as an efficient model to study these pathways as seen in a cell line derived from O. mossambicus brain tissue (OmB) that retains much of the osmotically induced proteome phenotypes observed in adult tissues of this animal. Furthermore, cell culture models can facilitate these studies by providing an enhanced means to isolate and examine individual components, such as proteins and the genes that encode them, of the mechanisms behind adaption to osmotic challenges. Valuable functional information can be obtained through observation of specific phenotypes caused by genetic manipulations of these components. CRISPR/Cas9 gene editing systems have proven to be a potent means to induce targeted genetic manipulations in cell culture from a variety of vertebrate taxa including fish. The objective of these experiments is to optimize strategies to implement CRISPR/Cas9 targeting of relevant previously identified genes in OmB cells to help decipher cellular hyperosmotic stress response pathways. In this work using genetically modified OmB cells, we have shown CRISPR/Cas9 gene targeting to be successful in this cell line through targeting and reduction of transgenic enhanced green fluorescent protein (EGFP) expression and established a puromycin selection system through stable integration of puromycin resistance. Additionally, this work has demonstrated multiple interspecies promoters, both fish and mammalian, to be suitable for ectopic gene expression in fish cells that can be used in future applications. The results indicate CRISPR/Cas9 has the potential to be a proficient means to manipulate osmotic stress response relevant genes in the OmB cell model.Support or Funding InformationSupported by NSF award 1656371 and BARD award IS‐4800‐15 R.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Trabecular bone structural variation in the human postcranial skeleton
Authors: Ryan Timothy M , Stephens Nicholas , Doershuk Lily J. , Saers Jaap P. P. , Jashashvili Tea , Carlson Kristian J. , Stock Jay T. , Gordon Adam D. 
Published: June 2021

Modern humans have relatively lightly built skeletons compared to other primates and earlier hominins which may predispose recent humans to bone‐related health risks such as osteopenia and osteoporosis. Although recent work suggests a relationship between higher activity/mobility and increased postcranial trabecular bone structure, the amount of variation in skeletal phenotype across modern humans and the role of declining activity/mobility and other factors in driving this variation remain unclear. The goal of this study is to characterize variation in trabecular bone structure in the human postcranial skeleton in relation to variation in subsistence strategy, mobility, and physical activity. The seventh cervical vertebral body, proximal humerus, proximal femur, and distal tibia from 60 young adult individuals from six populations were microCT scanned. These groups represented a behavioral/mobility gradient spanning from forager to post‐industrial populations. Bone volume fraction (BV/TV) and degree of anisotropy (DA) were quantified in the entire trabecular volume for each bone using Medtool 4.2. Results for each bone were mapped onto a 3D tetrahedral mesh and these meshes were registered using common morphological characters for visualization and analysis. For all groups BV/TV was highest in the cervical vertebra, followed by the proximal femur, distal tibia, and proximal humerus. DA was highest in the distal tibia, followed by the femur, humerus, and vertebra. The hunter‐gatherers had the highest BV/TV and lowest DA. Statistical comparisons of BV/TV and DA found significant differences among groups for the cervical vertebra (BV/TV) and distal tibia (BV/TV, DA). Comparisons of trabecular structure within each bone indicate broad similarities between groups with some unique patterns potentially reflective of behavioral and activity differences. The results demonstrate the potential for identifying functionally‐relevant trabecular bone patterns among skeletal elements, but indicate significant within and between individual variation that may obscure behavioral signals. The data may be useful in medical contexts looking to identify which postcranial elements are more diagnostic of or susceptible to osteopenia/osteoporosis, allowing for more targeted intervention.Support or Funding InformationFunding: NSF BCS‐1719187, NSF BCS‐1719140 RCUK/BBSRC grant BB/R01292X/1.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The plant social network: Volatiles and their release
Authors: Doudareva Natalia 
Published: June 2021

Plants have exploited the language of small chemicals for interacting with their environment more extensively than any other types of living organisms. An amazing diversity of volatile organic compounds (VOCs) released by plants play essential roles in their reproduction, defense, and communication, and influence atmospheric chemistry and climate. Plant VOCs are also used by humans as flavors, fragrances, biofuels, insecticides and pharmaceuticals. To date, the chemistry of plant volatiles is well understood, however, little is known about the biosynthesis of this diverse group of compounds and their release from the cell to the atmosphere. Presented results will show how the integration of metabolic profiling, functional genomic approach, targeted metabolic engineering with metabolic flux analysis and modeling can provide a comprehensive understanding of the regulation of flux through VOC metabolic networks. This presentation will also cover different aspects of volatile emission: from function in protecting plant reproductive organs via natural fumigation to promoting stigma development and seed yield. This presentation will also discuss molecular mechanisms responsible for deploying VOC from plant cells into the atmosphere.Support or Funding InformationThis work was supported by Grant IOS‐16555438 from the National Science Foundation and by the USDA National Institute of Food and Agriculture Hatch project 177845.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Evolution and the single cell: Metabolic diversity in tomato
Authors: Last Robert 
Published: June 2021

Research in the Last group focuses on specialized metabolism in glandular trichomes of tomato and other plants in the Solanaceae. Acylsugars – relatively simple metabolites typically composed of sucrose or glucose and C2 to C12 acylesters – are produced in the tip cell of the long hairs of domesticated and wild tomato. Despite being derived from simple chemical building blocks, tremendous variation in acylsugar structures is observed within and across species. Some of the changes in products and enzymatic activities have occurred over remarkably short evolutionary timeframes. The talk will describe our results documenting ‘recruitment’ of enzymes of central metabolism to acylsugar biosynthesis, as well as studies of BAHD acyltransferase evolution. I will emphasize how comparative biochemistry led to insights into how gene duplication, neofunctionalization and gene loss contributed to the impressive acylsugar diversity observed in domesticated and wild tomato species. Work towards understanding the evolutionary history of this metabolic network over tens of millions of years of evolution of the Solanaceae will be described.Support or Funding InformationNSF IOS‐1546617 NIH 1T32GM110523 NSF CBET‐1565232This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Mutation of a predicted DNA binding site on bacteriophage T4 Rad50 creates a constitutively active ATPase
Authors: Teklemariam Tibebe Antonios , Finnerty Ryan Michael , Nelson Scott William 
Published: June 2021

The Mre11/Rad50 (MR) complex uses ATP to repair DNA double strand breaks. The mechanistic details of how ATP hydrolysis relates to DNA binding and processing, as well as the associated structural changes that occur within the MR complex heterotetramer are not fully understood. An amino acid sequence‐based analysis predicted a patch of positively charged residues on bacteriophage T4 Rad50 as a potential DNA binding site. Specific mutations were generated to neutralize the charge at this site and the mutant proteins were biochemically characterized. Consistent with the bioinformatic predictions, the mutant proteins bound double‐stranded DNA with lesser affinity than the wild‐type enzyme. Surprisingly, ATP hydrolysis assays indicated that the mutations created an enzyme that was fully activated, even in the absence of bound activator DNA. DNA exonuclease assays suggest that the ATP hydrolyzed by the mutant proteins is somehow uncoupled from normal repetitive cleavage of nucleotides by the MR complex. All together, these findings suggest that the point mutations have stabilized a conformational state of Rad50 that is normally induced by DNA binding and clearly demonstrate the allosteric relationship between the substrate DNA and the activator ATP. A complete investigation of these residues and their effect on allostery will lead to a more complete picture of the steps involved in the repair of harmful DNA breaks.Support or Funding InformationNSF. Award number 1716269. The molecular mechanisms of the Mre11/Rad50 DNA repair complexThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Effects of Rfa2 N‐Terminal Phosphorylation on Adaptation Deficient Yeast
Authors: Hernandez Cristian Antonio , Baumgartner Trevor , Haring Stuart 
Published: June 2021

Determining the role of the Replication Factor A2 (Rfa2) N‐terminus on cell cycle regulation and DNA damage checkpoint progression is crucial for studying how cells prevent genetic defects. Cells must be able to efficiently and accurately repair DNA damage in a temporally‐controlled manner. If cells are unable to do so, they are at a very high risk of developing permanent DNA mutations, which are directly correlated with cancer and other cellular diseases. To prevent mutations, it is especially important for cells to be able to address DNA damage before they replicate their DNA or segregate their chromosomes by mitosis. Before the phases of the cell cycle that involve DNA metabolism (i.e., DNA synthesis and mitosis), checkpoints are elicited to provide the necessary time to do one last check to ensure that the genome is intact. The N‐terminus of the single‐stranded DNA‐binding protein Rfa2 plays a crucial role in the response to DNA damage, especially in regulating checkpoint function. Checkpoints are utilized by all eukaryotic cells and require precise coordination of many proteins. Using yeast as a model eukaryotic organism, gene deletions of checkpoint machinery required for checkpoint exit (adaptation) were generated to assess the ability of cells to progress through cell cycle checkpoints. We show here how Rfa2 modification affects adaptation when these genes are deleted, to determine the pathway through which Rfa2 mediates checkpoint exit and the return to cell growth.Support or Funding InformationNational Science Foundation (NSF‐CAREER‐1253723) to Stuart Haring.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.