Spermatogenesis in Drosophila melanogaster: Key Features and the Role of the NXF1 (Nuclear Export Factor) Protein

AbstractInteractions between microbial symbionts of metazoan hosts are emerging as key features of symbiotic systems. Little is known about the role of such interactions on the maintenance of symbiosis through host’s life cycle. We studied the influence of symbiotic bacteria on the maintenance of symbiotic yeast through metamorphosis of the fly Drosophila melanogaster. To this end we mimicked the development of larvae in natural fruit. In absence of bacteria yeast was never found in young adults. However, yeast could maintain through metamorphosis when larvae were inoculated with symbiotic bacteria isolated from D. melanogaster faeces. Furthermore, an Enterobacteriaceae favoured yeast transstadial maintenance. Because yeast is a critical symbiont of D. melanogaster flies, bacterial influence on host-yeast association may have consequences for the evolution of insect-yeast-bacteria tripartite symbiosis and their cooperation.Summary statementBacterial symbionts of Drosophila influence yeast maintenance through fly metamorphosis, a novel observation that may have consequences for the evolution of insect-yeast-bacteria interactions.

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The role of serine 190 in FOXO nuclear export and cell death induction in Drosophila melanogaster

Genes & Genomics ◽

10.1007/s13258-014-0182-0 ◽

2014 ◽

Vol 36 (4) ◽

pp. 475-483

Author(s):

Yoon Ki Hong ◽

Dahye Lee ◽

Soojin Hwang ◽

Se Min Bang ◽

Haemin Jeong ◽

...

Keyword(s):

Cell Death ◽

Drosophila Melanogaster ◽

Nuclear Export

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Influence of bacteria on the maintenance of a yeast during Drosophila melanogaster metamorphosis

Animal Microbiome ◽

10.1186/s42523-021-00133-0 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Robin Guilhot ◽

Antoine Rombaut ◽

Anne Xuéreb ◽

Kate Howell ◽

Simon Fellous

Keyword(s):

Saccharomyces Cerevisiae ◽

Drosophila Melanogaster ◽

Life Cycle ◽

Wild Isolate ◽

In The Wild ◽

Key Features

AbstractInteractions between microorganisms associated with metazoan hosts are emerging as key features of symbiotic systems. Little is known about the role of such interactions on the maintenance of host-microorganism association throughout the host’s life cycle. We studied the influence of extracellular bacteria on the maintenance of a wild isolate of the yeast Saccharomyces cerevisiae through metamorphosis of the fly Drosophila melanogaster reared in fruit. Yeasts maintained through metamorphosis only when larvae were associated with extracellular bacteria isolated from D. melanogaster faeces. One of these isolates, an Enterobacteriaceae, favoured yeast maintenance during metamorphosis. Such bacterial influence on host-yeast association may have consequences for the ecology and evolution of insect-yeast-bacteria symbioses in the wild.

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The Geography of Insight

10.1093/oso/9780190865122.001.0001 ◽

2018 ◽

Cited By ~ 2

Author(s):

Richard Foley

Keyword(s):

Collective Knowledge ◽

Key Features

This book, based on a philosopher’s experiences as dean over almost two decades, argues it is appropriate for the sciences and humanities to have different aims and for the values informing their inquiries also to be different. It maintains there are four core differences: (1) it is proper for the sciences but not the humanities to seek insights not limited to particular locations, times, or things; (2) the sciences but not the humanities value findings as independent as possible of the perspectives of the inquirers; (3) the sciences should be wholly descriptive while the humanities can also be concerned with prescriptive claims, which give expression to values; and (4) the sciences are organized to increase collective knowledge, whereas in the humanities individual insight is highly valued independently of its ability to generate consensus. Associated with these differences are secondary distinctions: different attitudes about an endpoint of inquiry; different notions of intellectual progress; different roles for expertise; different assumptions about simplicity and complexity; and different approaches to issues associated with consciousness. Taken together these distinctions constitute an intellectual geography of the humanities and sciences: a mapping of key features of their epistemology. In addition, the book discusses the role of universities in an era attached to sound bites and immediately useful results, and the importance of there being a healthy culture of research for both the sciences and humanities, one that treasures long-term intellectual achievements and whose presiding value is that with respect to many issues it ought not to be easy to have opinions.

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MULTIPLE ALLELE APPROACH TO THE STUDY OF GENES IN DROSOPHILA MELANOGASTER THAT ARE INVOLVED IN IMAGINAL DISC DEVELOPMENT

Genetics ◽

10.1093/genetics/89.2.355 ◽

1978 ◽

Vol 89 (2) ◽

pp. 355-370 ◽

Cited By ~ 2

Author(s):

Allen Shearn ◽

Grafton Hersperger ◽

Evelyn Hersperger ◽

Ellen Steward Pentz ◽

Paul Denker

Keyword(s):

Drosophila Melanogaster ◽

Phenotypic Variation ◽

Mutant Allele ◽

Imaginal Disc ◽

Reference Allele ◽

Multiple Allele ◽

Significant Difference ◽

Chromosome Mutations ◽

Cold Sensitive

ABSTRACT The phenotypes of five different lethal mutants of Drosophila melanogaster that have small imaginal discs were analyzed in detail. From these results, we inferred whether or not the observed imaginal disc phenotype resulted exclusively from a primary imaginal disc defect in each mutant. To examine the validity of these inferences, we employed a multiple-allele method. Lethal alleles of the five third-chromosome mutations were identified by screening EMS-treated chromosomes for those which fail to complement with a chromosome containing all five reference mutations. Twenty-four mutants were isolated from 13,197 treated chromosomes. Each of the 24 was then tested for complementation with each of the five reference mutants. There was no significant difference in the mutation frequencies at these five loci. The stage of lethality and the imaginal disc morphology of each mutant allele were compared to those of its reference allele in order to examine the range of defects to be found among lethal alleles of each locus. In addition, hybrids of the alleles were examined for intracistronic complementation. For two of the five loci, we detected no significant phenotypic variation among lethal alleles. We infer that each of the mutant alleles at these two loci cause expression of the null activity phenotype. However, for the three other loci, we did detect significant phenotypic variation among lethal alleles. In fact, one of the mutant alleles at each of these three loci causes no detectable imaginal disc defect. This demonstrates that attempting to assess the developmental role of a gene by studying a single mutant allele may lead to erroneous conclusions. As a byproduct of the mutagenesis procedure, we have isolated two dominant, cold-sensitive mutants.

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Phosphorylation of Serine 11 and Serine 92 as New Positive Regulators of Human Snail1 Function: Potential Involvement of Casein Kinase-2 and the cAMP-activated Kinase Protein Kinase A

Molecular Biology of the Cell ◽

10.1091/mbc.e09-06-0504 ◽

2010 ◽

Vol 21 (2) ◽

pp. 244-253 ◽

Cited By ~ 47

Author(s):

Matthew Reid MacPherson ◽

Patricia Molina ◽

Serhiy Souchelnytskyi ◽

Christer Wernstedt ◽

Jorge Martin-Pérez ◽

...

Keyword(s):

Nuclear Export ◽

Tumor Metastasis ◽

Epithelial Mesenchymal Transition ◽

Cop9 Signalosome ◽

Mesenchymal Transition ◽

Depth Analysis ◽

Positive Regulators

Snail1 is a major factor for epithelial-mesenchymal transition (EMT), an important event in tumor metastasis and in other pathologies. Snail1 is tightly regulated at transcriptional and posttranscriptional levels. Control of Snail1 protein stability and nuclear export by GSK3β phosphorylation is important for Snail1 functionality. Stabilization mechanisms independent of GSK3β have also been reported, including interaction with LOXL2 or regulation of the COP9 signalosome by inflammatory signals. To get further insights into the role of Snail1 phosphorylation, we have performed an in-depth analysis of in vivo human Snail1 phosphorylation combined with mutational studies. We identify new phosphorylation sites at serines 11, 82, and 92 and confirmed previously suggested phosphorylations at serine 104 and 107. Serines 11 and 92 participate in the control of Snail1 stability and positively regulate Snail1 repressive function and its interaction with mSin3A corepressor. Furthermore, serines 11 and 92 are required for Snail1-mediated EMT and cell viability, respectively. PKA and CK2 have been characterized as the main kinases responsible for in vitro Snail1 phosphorylation at serine 11 and 92, respectively. These results highlight serines 11 and 92 as new players in Snail1 regulation and suggest the participation of CK2 and PKA in the modulation of Snail1 functionality.

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Dual roles for the Drosophila PI 4-kinase Four wheel drive in localizing Rab11 during cytokinesis

The Journal of Cell Biology ◽

10.1083/jcb.200908107 ◽

2009 ◽

Vol 187 (6) ◽

pp. 847-858 ◽

Cited By ~ 88

Author(s):

Gordon Polevoy ◽

Ho-Chun Wei ◽

Raymond Wong ◽

Zsofia Szentpetery ◽

Yeun Ju Kim ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Critical Role ◽

Successful Completion ◽

Dual Roles ◽

Recycling Endosome ◽

Golgi Membranes ◽

Wheel Drive ◽

Dividing Cells ◽

Four Wheel Drive

Successful completion of cytokinesis relies on addition of new membrane, and requires the recycling endosome regulator Rab11, which localizes to the midzone. Despite the critical role of Rab11 in this process, little is known about the formation and composition of Rab11-containing organelles. Here, we identify the phosphatidylinositol (PI) 4-kinase III β Four wheel drive (Fwd) as a key regulator of Rab11 during cytokinesis in Drosophila melanogaster spermatocytes. We show Fwd is required for synthesis of PI 4-phosphate (PI4P) on Golgi membranes and for formation of PI4P-containing secretory organelles that localize to the midzone. Fwd binds and colocalizes with Rab11 on Golgi membranes, and is required for localization of Rab11 in dividing cells. A kinase-dead version of Fwd also binds Rab11 and partially restores cytokinesis to fwd mutant flies. Moreover, activated Rab11 partially suppresses loss of fwd. Our data suggest Fwd plays catalytic and noncatalytic roles in regulating Rab11 during cytokinesis.

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Shame and Honor: Aristotle’s Thumos as a Basic Desire

Apeiron ◽

10.1515/apeiron-2017-0033 ◽

2018 ◽

Vol 51 (1) ◽

pp. 73-95

Author(s):

Victor Saenz

Keyword(s):

Moral Education ◽

Social Value ◽

The Other ◽

Moral Exemplars ◽

Virtuous Agent ◽

Rational Desire ◽

Key Features ◽

Scholarly Attention ◽

Rational Motivation

Abstract One of three basic types of desire, claims Aristotle, is thumos (‘spirit,’ ‘passion,’ ‘heart,’ ‘anger,’ ‘impulse’). The other two are epithumia (‘appetite’) and boulêsis (‘wish,’ ‘rational desire’). Yet, he never gives us an account of thumos; it has also received relatively little scholarly attention. I argue that thumos has two key features. First, it is able to cognize what I call ‘social value,’ the agent’s own perceived standing relative to others in a certain domain. In human animals, shame and honor are especially important manifestations of social value. Second, thumos provides non-rational motivation to pursue what affirms the agent’s social value and avoid what denies it. Interpretations that hold thumos just is anger, or that its object is the fine (kalon), I argue, are mistaken. My account also explains the role of thumos in moral education. In a virtuous agent thumos will be affectively attuned to the correct social rankings; it will take the practically wise, the lovers of the fine, or moral exemplars, as authorities.

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