scholarly journals The genome of the jellyfish Clytia hemisphaerica and the evolution of the cnidarian life-cycle

2018 ◽  
Author(s):  
Lucas Leclère ◽  
Coralie Horin ◽  
Sandra Chevalier ◽  
Pascal Lapébie ◽  
Philippe Dru ◽  
...  

Jellyfish (medusae) are a distinctive life-cycle stage of medusozoan cnidarians. They are major marine predators, with integrated neurosensory, muscular and organ systems. The genetic foundations of this complex form are largely unknown. We report the draft genome of the hydrozoan jellyfish Clytia hemisphaerica and use multiple transcriptomes to determine gene use across life-cycle stages. Medusa, planula larva and polyp are each characterised by distinct transcriptome signatures reflecting abrupt life cycle transitions, and all deploy a mixture of phylogenetically old and new genes. Medusa specific transcription factors, including many with bilaterian orthologs, associate with diverse neurosensory structures. Compared to Clytia, the polyp-only hydrozoan Hydra has lost many of the medusa-expressed transcription factors, despite similar overall rates of gene content and sequence evolution. Absence of expression and gene loss among Clytia orthologs of genes patterning the anthozoan aboral pole, secondary axis and endomesoderm support simplification of planulae and polyps in Hydrozoa, including loss of bilateral symmetry. Consequently, although the polyp and planula are generally considered the ancestral cnidarian forms, in Clytia the medusa maximally deploys ancestral cnidarian–bilaterian transcription factor gene complexity.

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Vikas D. Trivedi ◽  
Pramod Kumar Jangir ◽  
Rakesh Sharma ◽  
Prashant S. Phale

Abstract Carbaryl (1-naphthyl N-methylcarbamate) is a most widely used carbamate pesticide in the agriculture field. Soil isolate, Pseudomonas sp. strain C5pp mineralizes carbaryl via 1-naphthol, salicylate and gentisate, however the genetic organization and evolutionary events of acquisition and assembly of pathway have not yet been studied. The draft genome analysis of strain C5pp reveals that the carbaryl catabolic genes are organized into three putative operons, ‘upper’, ‘middle’ and ‘lower’. The sequence and functional analysis led to identification of new genes encoding: i) hitherto unidentified 1-naphthol 2-hydroxylase, sharing a common ancestry with 2,4-dichlorophenol monooxygenase; ii) carbaryl hydrolase, a member of a new family of esterase; and iii) 1,2-dihydroxy naphthalene dioxygenase, uncharacterized type-II extradiol dioxygenase. The ‘upper’ pathway genes were present as a part of a integron while the ‘middle’ and ‘lower’ pathway genes were present as two distinct class-I composite transposons. These findings suggest the role of horizontal gene transfer event(s) in the acquisition and evolution of the carbaryl degradation pathway in strain C5pp. The study presents an example of assembly of degradation pathway for carbaryl.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Oscar Daniel Rivera Baena ◽  
Maria Valentina Clavijo Mesa ◽  
Carmen Elena Patino Rodriguez ◽  
Fernando Jesus Guevara Carazas

PurposeThis paper aims to determine the stage of the life cycle where the trucks of a waste collection fleet from a Colombian city are located through a reliability approach. The reliability analysis and the evaluation of curve of operational costs allow to know the moment in which it is necessary to make decisions regarding an asset, its maintenance or possible replacement.Design/methodology/approachFor a dataset presented as maintenance work orders, the time to failures (TTFs) for each vehicle in the fleet were calculated. Then, a probability density function for those TTFs was fitted to locate each vehicle in a region of the bathtub curve and to calculate the reliability of the whole fleet. A general functional analysis was also developed to understand the function of the vehicles.FindingsIt was possible to determine that the largest proportion of the fleet was in the final stage of the life cycle, in this sense, the entire fleet represent critical assets which in most of cases could be worth replacement or overhaul.Originality/valueIn this study, an address is exposed for the identification of critical equipment by reliability and statistical analysis. This analysis is also integrated with the maintenance management process. This is a broadly interested topic since it allows to support the maintenance and operational decision-making process, indicating the focus of resource allocation all over the entire asset life cycle.


1994 ◽  
Vol 14 (5) ◽  
pp. 2975-2984
Author(s):  
H Charest ◽  
G Matlashewski

Leishmania protozoans are the causative agents of leishmaniasis, a major parasitic disease in humans. During their life cycle, Leishmania protozoans exist as flagellated promastigotes in the sand fly vector and as nonmotile amastigotes in the mammalian hosts. The promastigote-to-amastigote transformation occurs in the phagolysosomal compartment of the macrophage cell and is a critical step for the establishment of the infection. To study this cytodifferentiation process, we differentially screened an amastigote cDNA library with life cycle stage-specific cDNA probes and isolated seven cDNAs representing amastigote-specific transcripts. Five of these were closely related (A2 series) and recognized, by Northern (RNA) blot analyses, a 3.5-kb transcript in amastigotes and in amastigote-infected macrophages. Expression of the amastigote-specific A2 gene was induced in promastigotes when they were transferred from culture medium at 26 degrees C and pH 7.4 to medium at 37 degrees C and pH 4.5, conditions which mimic the macrophage phagolysosomal environment. A2 genes are clustered in tandem arrays, and a 6-kb fragment corresponding to a unit of the cluster was cloned and partially sequenced. An open reading frame found within the A2-transcribed region potentially encoded a 22-kDa protein containing repetitive sequences. The recombinant A2 protein produced in Escherichia coli cells was specifically recognized by immune serum from a patient with visceral leishmaniasis. The A2 protein repetitive element has strong homology with an S antigen of Plasmodium falciparum, the protozoan parasite responsible for malaria. Both the A2 protein of Leishmania donovani and the S antigen of P. falciparum are stage specific and developmentally expressed in mammalian hosts.


2016 ◽  
Vol 36 (1) ◽  
pp. 243-253 ◽  
Author(s):  
Sandra F. Gonçalves ◽  
Maria D. Pavlaki ◽  
Rafael Lopes ◽  
Julia Hammes ◽  
Julián Alberto Gallego-Urrea ◽  
...  

2020 ◽  
Vol 12 (10) ◽  
pp. 4265 ◽  
Author(s):  
Vicent Penadés-Plà ◽  
David Martínez-Muñoz ◽  
Tatiana García-Segura ◽  
Ignacio J. Navarro ◽  
Víctor Yepes

Most of the definitions of sustainability include three basic pillars: economic, environmental, and social. The economic pillar has always been evaluated but not necessarily in the sense of economic sustainability. On the other hand, the environmental pillar is increasingly being considered, while the social pillar is weakly developed. Focusing on the environmental and social pillars, the use of methodologies to allow a wide assessment of these pillars and the integration of the assessment in a few understandable indicators is crucial. This article is structured into two parts. In the first part, a review of life cycle impact assessment methods, which allow a comprehensive assessment of the environmental and social pillars, is carried out. In the second part, a complete environmental and social sustainability assessment is made using the ecoinvent database and ReCiPe method, for the environmental pillar, and SOCA database and simple Social Impact Weighting method, for the social pillar. This methodology was used to compare three optimized bridges: two box-section post-tensioned concrete road bridges with a variety of initial and maintenance characteristics, and a pre-stressed concrete precast bridge. The results show that there is a high interrelation between the environmental and social impact for each life cycle stage.


2018 ◽  
Vol 10 (10) ◽  
pp. 3516 ◽  
Author(s):  
Angelina Roša (Rosha) ◽  
Natalja Lace

Organizations need innovation to be competitive and sustainable on their marketplace. Sustainable performance is an important precondition for growth and development. In spite of a body of literature, non-financial factors of sustainable performance remain an open issue. Coaching has gained considerable attention in the business world for its impact on sustainable performance. The current research investigates the use of coaching interaction to facilitate organizational sustainable growth and development in the context of Miller and Friesen’s five stage life-cycle model. The expert opinion survey is chosen as a central method of research. The questionnaire is developed on the literature review that is focused on the drivers for sustainable development throughout the life cycle, and the features of coaching that accelerate these driving forces. Fifteen experts took part in the survey conducted from November 2017 to January 2018. The results are estimated by considering the competence coefficient for each expert. The findings led to creation of an open innovation model, which displays relationships between the appropriate coaching forms and types and the organizational life cycle stages. The developed model enables choosing the optimal way of coaching delivery at any life cycle stage. This model is particularly valuable for the coaching support programs.


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