scholarly journals Does environmental stress affect cortisol biodistribution in freshwater mussels?

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
A Ronja D Binder ◽  
Michael W Pfaffl ◽  
Felix Hiltwein ◽  
Juergen Geist ◽  
Sebastian Beggel
Keyword(s):  
Sodium Chloride ◽  
Environmental Stress ◽  
Steroid Hormones ◽  
Freshwater Mussels ◽  
Model Organism ◽  
Cortisol Extraction ◽  
Different Tissues

Lay summaries: Since little is known about invertebrate steroid hormones, we established a cortisol extraction and quantification protocol via ELISA in mussels, in the model organism Anodonta anatina. Additionally, we quantified cortisol biodistribution and redistribution in five different tissues after treatment with either copper (II) chloride, sodium chloride or algae feed.

Effect of dietary potassium chloride in borderline hypertensive rats.

1992 ◽  
Vol 3 (2) ◽  
pp. 188-195
Author(s):  
G F DiBona ◽  
S Y Jones
Keyword(s):  
Sodium Chloride ◽  
Environmental Stress ◽  
Potassium Chloride ◽  
Spontaneously Hypertensive Rat ◽  
Dietary Sodium ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Hypertensive Rat ◽  
Dietary Potassium ◽  
Sodium Chloride Intake

The borderline hypertensive rat is the first filial offspring of the spontaneously hypertensive rat and the Wistar-Kyoto rat. With increased dietary sodium chloride intake, the borderline hypertensive rat develops hypertension and exaggerated cardiovascular and renal responses to acute environmental stress, similar to those observed in the hypertensive spontaneously hypertensive rat parent. In other models of sodium chloride-sensitive hypertension with different genetic background (Dahl rat), dietary potassium chloride supplementation protects against the development of hypertension, increased sympathetic nervous system activity, and exaggerated responses to acute environmental stress. This investigation sought to determine whether the dietary sodium chloride-induced development of both the hypertension and the exaggerated responses to acute environmental stress could be reversed or prevented by increased dietary potassium chloride intake. Dietary potassium chloride intake was increased with a 1% potassium chloride drinking solution either after 12 wk of 8% sodium chloride intake (reversal) or concomitant with the onset of 12 wk of 8% sodium chloride intake (prevention). An increase in dietary potassium chloride intake did not reverse or prevent the development of either the hypertension or the exaggerated cardiovascular and renal responses to acute environmental stress in borderline hypertensive rats fed 8% sodium chloride. It is concluded that the difference in genetic background between borderline hypertensive rats and other models of sodium chloride-sensitive hypertension is an important determinant of the protective effect of dietary potassium chloride supplementation.

scholarly journals Enhancement of de novo sequencing, assembly and annotation of the Mongolian gerbil genome with transcriptome sequencing and assembly from several different tissues

2019 ◽  
Author(s):  
Shifeng Cheng ◽  
Yuan Fu ◽  
Yaolei Zhang ◽  
Wenfei Xian ◽  
Hongli Wang ◽  
...  
Keyword(s):  
Genome Size ◽  
Mongolian Gerbil ◽  
Transcriptome Sequencing ◽  
De Novo ◽  
Model Organism ◽  
Meriones Unguiculatus ◽  
Transcriptome Data ◽  
Illumina Hiseq ◽  
Tissue Samples ◽  
Different Tissues

Abstract BACKGROUND: The Mongolian gerbil (Meriones unguiculatus) has historically been used as a model organism for the auditory and visual systems, stroke/ischemia, epilepsy and aging related research since 1935 when laboratory gerbils were separated from their wild counterparts. In this study we report genome sequencing, assembly, and annotation further supported by transcriptome sequencing and assembly from 27 different tissues samples. RESULTS: The genome was assembled using Illumina HiSeq 2000 and resulted in a final genome size of 2.54 Gbp with contig and scaffold N50 values of 31.4 Kbp and 500.0 Kbp, respectively. Based on the k-mer estimated genome size of 2.48 Gbp, the assembly appears to be complete. The genome annotation was supported by transcriptome data that identified 31 769 (>2000bp) predicted protein-coding genes across 27 tissue samples. A BUSCO search of 3023 mammalian groups resulted in 86% of curated single copy orthologs present among predicted genes, indicating a high level of completeness of the genome. CONCLUSIONS: We report a de novo assembly of the Mongolian gerbil genome that was further enhanced by assembly of transcriptome data from several tissues. Sequencing of this genome increases the utility of the gerbil as a model organism, opening the availability of now widely used genetic tools.

scholarly journals I Spy in the Developing Fly a Multitude of Ways to Die

2018 ◽  
Vol 6 (4) ◽  
pp. 26 ◽  
Author(s):  
Alla Yalonetskaya ◽  
Albert Mondragon ◽  
Johnny Elguero ◽  
Kimberly McCall
Keyword(s):  
Cell Proliferation ◽  
Cell Death ◽  
Nervous System ◽  
Programmed Cell Death ◽  
Apoptotic Cell ◽  
Model Organism ◽  
Cell Numbers ◽  
Genetic Techniques ◽  
Developmental Cell Death ◽  
Different Tissues

Cell proliferation and cell death are two opposing, yet complementary fundamental processes in development. Cell proliferation provides new cells, while developmental programmed cell death adjusts cell numbers and refines structures as an organism grows. Apoptosis is the best-characterized form of programmed cell death; however, there are many other non-apoptotic forms of cell death that occur throughout development. Drosophila is an excellent model for studying these varied forms of cell death given the array of cellular, molecular, and genetic techniques available. In this review, we discuss select examples of apoptotic and non-apoptotic cell death that occur in different tissues and at different stages of Drosophila development. For example, apoptosis occurs throughout the nervous system to achieve an appropriate number of neurons. Elsewhere in the fly, non-apoptotic modes of developmental cell death are employed, such as in the elimination of larval salivary glands and midgut during metamorphosis. These and other examples discussed here demonstrate the versatility of Drosophila as a model organism for elucidating the diverse modes of programmed cell death.

scholarly journals Sterol metabolism in the filasterean Capsaspora owczarzaki has features that resemble both fungi and animals

Open Biology ◽  
2016 ◽  
Vol 6 (7) ◽  
pp. 160029 ◽  
Author(s):  
Sebastián R. Najle ◽  
María Celeste Molina ◽  
Iñaki Ruiz-Trillo ◽  
Antonio D. Uttaro
Keyword(s):  
Transcriptional Regulation ◽  
Life Cycle ◽  
Steroid Hormones ◽  
Lipid Rafts ◽  
De Novo ◽  
Model Organism ◽  
Signalling Pathways ◽  
Sterol Metabolism ◽  
Physiological Processes ◽  
Biochemical Analyses

Sterols are essential for several physiological processes in most eukaryotes. Sterols regulate membrane homeostasis and participate in different signalling pathways not only as precursors of steroid hormones and vitamins, but also through its role in the formation of lipid rafts. Two major types of sterols, cholesterol and ergosterol, have been described so far in the opisthokonts, the clade that comprise animals, fungi and their unicellular relatives. Cholesterol predominates in derived bilaterians, whereas ergosterol is what generally defines fungi. We here characterize, by a combination of bioinformatic and biochemical analyses, the sterol metabolism in the filasterean Capsaspora owczarzaki , a close unicellular relative of animals that is becoming a model organism. We found that C. owczarzaki sterol metabolism combines enzymatic activities that are usually considered either characteristic of fungi or exclusive to metazoans. Moreover, we observe a differential transcriptional regulation of this metabolism across its life cycle. Thus, C. owczarzaki alternates between synthesizing 7-dehydrocholesterol de novo, which happens at the cystic stage, and the partial conversion—via a novel pathway—of incorporated cholesterol into ergosterol, the characteristic fungal sterol, in the filopodial and aggregative stages.

Relationship of cytochrome content to the sensitivity of bacteria to NaCl on freezing and thawing

1977 ◽  
Vol 23 (4) ◽  
pp. 413-419 ◽  
Author(s):  
Sai K. Lee ◽  
Peter H. Calcott ◽  
Robert A. MacLeod
Keyword(s):  
Sodium Chloride ◽  
Respiratory Activity ◽  
Membrane Integrity ◽  
Model Organism ◽  
Salt Sensitivity ◽  
Freezing And Thawing ◽  
Whole Cells ◽  
E Coli ◽  
Membrane Components ◽  
Cytochrome Content

Eight species of bacteria representing rod, coccus, gram-positive, and gram-negative forms were tested for their sensitivity to sodium chloride during freezing and thawing. Six of the eight species tested were salt-sensitive, though to different degrees, while Lactobacillus casei and Streptococcus faecalis were resistant. Escherichia coli grown anaerobically exhibited only 38% of the salt sensitivity of aerobically grown cells. Analysis of cytochrome pigments in the organisms revealed that the six sensitive organisms all contained these pigments but in varying amounts, while the two resistant ones were devoid of them. Anaerobically grown E. coli contained 50% of the cytochromes of aerobically grown cells. A relationship between cytochrome content of the organisms and salt sensitivity during freezing and thawing was demonstrated with a correlation coefficient of 0.76 (P < 0.05); the higher the cytochrome content, the more salt-sensitive the organism. This indicated that 58% of the salt sensitivity was due to the cytochrome content.Using a model organism, E. coli, the effect of salt during freezing and thawing on the respiratory activity was examined. Freezing and thawing in water or saline decreased the respiration by whole cells of substrates expected to be NAD-linked while NADH-stimulated respiration was increased. In cell-free extracts derived from unfrozen cells or those frozen and thawed in water or saline, the respiration of ascorbate plus N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD) was constant. The respiration of NADH, succinate, and lactate in cell-free extracts derived from cells frozen and thawed in saline was reduced compared with those extracts derived from unfrozen cells or cells frozen and thawed in water. Studies with E. coli showed that the decreased respiratory activity caused by disruptions in the electron-transport chain could not account for the salt sensitivity on freezing and thawing. More likely, salt sensitivity is related to the presence of bonds between cytochromes and other membrane components which are disrupted by sodium chloride on freezing and thawing. This would then result in loss of membrane integrity and function.

scholarly journals A comprehensive rat transcriptome built from large scale RNA-seq-based annotation

2020 ◽  
Vol 48 (15) ◽  
pp. 8320-8331
Author(s):  
Xiangjun Ji ◽  
Peng Li ◽  
James C Fuscoe ◽  
Geng Chen ◽  
Wenzhong Xiao ◽  
...  
Keyword(s):  
Gene Expression ◽  
Significant Influence ◽  
Large Scale ◽  
Expression Patterns ◽  
Model Organism ◽  
Rna Seq ◽  
Disease Mechanisms ◽  
Expression Studies ◽  
Gene Expression Studies ◽  
Different Tissues

Abstract The rat is an important model organism in biomedical research for studying human disease mechanisms and treatments, but its annotated transcriptome is far from complete. We constructed a Rat Transcriptome Re-annotation named RTR using RNA-seq data from 320 samples in 11 different organs generated by the SEQC consortium. Totally, there are 52 807 genes and 114 152 transcripts in RTR. Transcribed regions and exons in RTR account for ∼42% and ∼6.5% of the genome, respectively. Of all 73 074 newly annotated transcripts in RTR, 34 213 were annotated as high confident coding transcripts and 24 728 as high confident long noncoding transcripts. Different tissues rather than different stages have a significant influence on the expression patterns of transcripts. We also found that 11 715 genes and 15 852 transcripts were expressed in all 11 tissues and that 849 house-keeping genes expressed different isoforms among tissues. This comprehensive transcriptome is freely available at http://www.unimd.org/rtr/. Our new rat transcriptome provides essential reference for genetics and gene expression studies in rat disease and toxicity models.

scholarly journals CSN5A Subunit of COP9 Signalosome Temporally Buffers Response to Heat in Arabidopsis

Biomolecules ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 805
Author(s):  
Amit Kumar Singh ◽  
Brijesh Singh Yadav ◽  
Shanmuhapreya Dhanapal ◽  
Mark Berliner ◽  
Alin Finkelshtein ◽  
...  
Keyword(s):  
Heat Stress ◽  
Environmental Stress ◽  
Lateral Roots ◽  
Model Organism ◽  
Immunoblot Analysis ◽  
Auxin Signaling ◽  
Plant Responses ◽  
Stress Studies ◽  
Evolutionarily Conserved

The COP9 (constitutive photomorphogenesis 9) signalosome (CSN) is an evolutionarily conserved protein complex which regulates various growth and developmental processes. However, the role of CSN during environmental stress is largely unknown. Using Arabidopsis as model organism, we used CSN hypomorphic mutants to study the role of the CSN in plant responses to environmental stress and found that heat stress specifically enhanced the growth of csn5a-1 but not the growth of other hypomorphic photomorphogenesis mutants tested. Following heat stress, csn5a-1 exhibits an increase in cell size, ploidy, photosynthetic activity, and number of lateral roots and an upregulation of genes connected to the auxin response. Immunoblot analysis revealed an increase in deneddylation of CUL1 but not CUL3 following heat stress in csn5a-1, implicating improved CUL1 activity as a basis for the improved growth of csn5a-1 following heat stress. Studies using DR5::N7-VENUS and DII-VENUS reporter constructs confirm that the heat-induced growth is due to an increase in auxin signaling. Our results indicate that CSN5A has a specific role in deneddylation of CUL1 and that CSN5A is required for the recovery of AUX/IAA repressor levels following recurrent heat stress to regulate auxin homeostasis in Arabidopsis.

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