scholarly journals Septins are involved at the early stages of macroautophagy inS. cerevisiae

2016 ◽  
Author(s):  
Gaurav Barve ◽  
Shreyas Sridhar ◽  
Amol Aher ◽  
Sunaina Singh ◽  
Lakshmeesha K.N. ◽  
...  
Keyword(s):  
Membrane Vesicle ◽  
Degradation Pathway ◽  
Permissive Temperature ◽  
Autophagosome Formation ◽  
Double Membrane ◽  
Early Stages ◽  
Gtp Binding ◽  
Bud Neck ◽  
Ts Mutant

Autophagy is a conserved cellular degradation pathway wherein a double membrane vesicle, called as an autophagosome captures longlived proteins, damaged or superfluous organelles and delivers to the lysosome for degradation1. We have identified a novel role for septins in autophagy. Septins are GTP-binding proteins that localize at the bud-neck and are involved in cytokinesis in budding yeast2. We show that septins under autophagy prevalent conditions are majorly localized to the cytoplasm in the form of punctate structures. Further, we report that septins not only localize to pre-autophagosomal structure (PAS) but also to autophagosomes in the form of punctate structures. Interestingly, septins also form small non-canonical rings around PAS during autophagy. Furthermore, we observed that in one of the septin Ts" mutant,cdc10-5, the anterograde trafficking of Atg9 was affected at the non-permissive temperature (NPT). All these results suggest a role of septins in early stages of autophagy during autophagosome formation.

scholarly journals The conserved oligomeric Golgi complex is involved in double-membrane vesicle formation during autophagy

2010 ◽  
Vol 188 (1) ◽  
pp. 101-114 ◽  
Author(s):  
Wei-Lien Yen ◽  
Takahiro Shintani ◽  
Usha Nair ◽  
Yang Cao ◽  
Brian C. Richardson ◽  
...  
Keyword(s):  
Membrane Vesicle ◽  
Autophagosome Formation ◽  
Double Membrane ◽  
Complex Part ◽  
Cog Complex ◽  
Conserved Oligomeric Golgi Complex ◽  
Conserved Oligomeric Golgi ◽  
Critical Components ◽  
Molecular Components ◽  
Related Proteins

Macroautophagy is a catabolic pathway used for the turnover of long-lived proteins and organelles in eukaryotic cells. The morphological hallmark of this process is the formation of double-membrane autophagosomes that sequester cytoplasm. Autophagosome formation is the most complex part of macroautophagy, and it is a dynamic event that likely involves vesicle fusion to expand the initial sequestering membrane, the phagophore; however, essentially nothing is known about this process including the molecular components involved in vesicle tethering and fusion. In this study, we provide evidence that the subunits of the conserved oligomeric Golgi (COG) complex are required for double-membrane cytoplasm to vacuole targeting vesicle and autophagosome formation. COG subunits localized to the phagophore assembly site and interacted with Atg (autophagy related) proteins. In addition, mutations in the COG genes resulted in the mislocalization of Atg8 and Atg9, which are critical components involved in autophagosome formation.

scholarly journals INVOLVEMENT OF GENE 49 IN RECOMBINATION OF BACTERIOPHAGE T4

Genetics ◽  
1983 ◽  
Vol 104 (1) ◽  
pp. 1-9
Author(s):  
Junichi Miyazaki ◽  
Yeikou Ryo ◽  
Teiichi Minagawa
Keyword(s):  
Dna Replication ◽  
Gene Function ◽  
Bacteriophage T4 ◽  
Temperature Sensitive ◽  
Permissive Temperature ◽  
Nonpermissive Temperature ◽  
Recombinant Frequency ◽  
Defective Mutant ◽  
Ts Mutant

ABSTRACT The role of T4 gene 49 in recombination was investigated using its conditional-lethal amber (am) and temperature-sensitive (ts) mutants. When measured in genetic tests, defects in gene 49 produced a recombination-deficient phenotype. However, DNA synthesized in cells infected with a ts mutant (tsC9) at a nonpermissive temperature appeared to be in a recombinogenic state: after restitution of gene function by shifting to a permissive temperature, the recombinant frequency among progeny increased rapidly even when DNA replication was blocked by an inhibitor. Growth of a gene 49-defective mutant was suppressed by an additional mutation in gene uvs X, but recombination between rII markers was not.

scholarly journals RAB18 impacts autophagy via lipid droplet-derived lipid transfer and is rescued by ATG9A

2018 ◽  
Author(s):  
Fazilet Bekbulat ◽  
Daniel Schmitt ◽  
Anne Feldmann ◽  
Heike Huesmann ◽  
Stefan Eimer ◽  
...  
Keyword(s):  
Lipid Droplet ◽  
Transmembrane Protein ◽  
Degradation Pathway ◽  
Rab Gtpase ◽  
Lipid Transfer ◽  
Lysosomal Degradation ◽  
Autophagosome Formation ◽  
Autophagic Activity ◽  
Rescue Mechanism

AbstractAutophagy is a lysosomal degradation pathway that mediates protein and organelle turnover and maintains cellular homeostasis. Autophagosomes transport cargo to lysosomes and their formation is dependent on an appropriate lipid supply. Here, we show that the knockout of the RAB GTPase RAB18 interferes with lipid droplet (LD) metabolism, resulting in an impaired fatty acid mobilization. The reduced LD-derived lipid availability influences autophagy and provokes adaptive modifications of the autophagy network, which include increased ATG2B expression and ATG12-ATG5 conjugate formation as well as enhanced ATG2B and ATG9A phosphorylation. Phosphorylation of ATG9A directs this transmembrane protein to the site of autophagosome formation and this particular modification is sufficient to rescue autophagic activity under basal conditions in the absence of RAB18. However, it is incapable of enabling an increased autophagy under inductive conditions. Thus, we illustrate the role of RAB18 in connecting LDs and autophagy, further emphasize the importance of LD-derived lipids for the degradative pathway, and characterize an ATG9A phosphorylation-dependent autophagy rescue mechanism as an adaptive response that maintains autophagy under conditions of reduced LD-derived lipid availability.

scholarly journals The Atg8 Conjugation System Is Indispensable for Proper Development of Autophagic Isolation Membranes in Mice

2008 ◽  
Vol 19 (11) ◽  
pp. 4762-4775 ◽  
Author(s):  
Yu-shin Sou ◽  
Satoshi Waguri ◽  
Jun-ichi Iwata ◽  
Takashi Ueno ◽  
Tsutomu Fujimura ◽  
...  
Keyword(s):  
Essential Role ◽  
Degradation Pathway ◽  
Conjugation System ◽  
Autophagosome Formation ◽  
Gene Encoding ◽  
Genetic Studies ◽  
Evolutionarily Conserved ◽  
Deficient Mice ◽  
Mouse Genetic

Autophagy is an evolutionarily conserved bulk-protein degradation pathway in which isolation membranes engulf the cytoplasmic constituents, and the resulting autophagosomes transport them to lysosomes. Two ubiquitin-like conjugation systems, termed Atg12 and Atg8 systems, are essential for autophagosomal formation. In addition to the pathophysiological roles of autophagy in mammals, recent mouse genetic studies have shown that the Atg8 system is predominantly under the control of the Atg12 system. To clarify the roles of the Atg8 system in mammalian autophagosome formation, we generated mice deficient in Atg3 gene encoding specific E2 enzyme for Atg8. Atg3-deficient mice were born but died within 1 d after birth. Conjugate formation of mammalian Atg8 homologues was completely defective in the mutant mice. Intriguingly, Atg12–Atg5 conjugation was markedly decreased in Atg3-deficient mice, and its dissociation from isolation membranes was significantly delayed. Furthermore, loss of Atg3 was associated with defective process of autophagosome formation, including the elongation and complete closure of the isolation membranes, resulting in malformation of the autophagosomes. The results indicate the essential role of the Atg8 system in the proper development of autophagic isolation membranes in mice.

The role of ‘maengyak’ in early stages of relationship between Joseon and Qing

2016 ◽  
Vol 78 ◽  
pp. 51-85
Author(s):  
Ho-Hyun Nam
Keyword(s):  
Early Stages

Injecting Knowledge

2017 ◽  
Author(s):  
Lucia Dacome
Keyword(s):  
Eighteenth Century ◽  
Blood Vessels ◽  
Comparative Perspective ◽  
Anatomical Models ◽  
Early Stages ◽  
The Creation ◽  
Cabinet Of Curiosities

Chapter 7 furthers the analysis of the role of anatomical models as cultural currencies capable of transferring value. It does so by expanding the investigation of the early stages of anatomical modelling to include a new setting. In particular, it follows the journey of the Palermitan anatomist and modeller Giuseppe Salerno and his anatomical ‘skeleton’—a specimen that represented the body’s complex web of blood vessels and was presented as the result of anatomical injections. Although Salerno was headed towards Bologna, a major centre of anatomical modelling, he ended his journey in Naples after the nobleman Raimondo di Sangro purchased the skeleton for his own cabinet of curiosities. This chapter considers the creation and viewing of an anatomical display in di Sangro’s Neapolitan Palace from a comparative perspective that highlights how geography and locality played an important part in shaping the culture of mid-eighteenth-century anatomical modelling.

Limited Influence? The Role of the Party of European Socialists in Shaping Social Democracy in Central and Eastern Europe

2011 ◽  
Vol 46 (1) ◽  
pp. 32-55 ◽  
Author(s):  
Michael Holmes ◽  
Simon Lightfoot
Keyword(s):  
Eastern Europe ◽  
Central And Eastern Europe ◽  
Social Democracy ◽  
Social Democratic ◽  
Academic Literature ◽  
Early Stages ◽  
European Norm ◽  
Democratic Parties ◽  
Social Democratic Parties

AbstractThis article looks at the role of the Party of European Socialists (PES) in its attempts to shape social democratic parties in Central and Eastern Europe (CEE) towards a West European norm. It discusses how existing views in the academic literature on the role of transnational parties are inadequate. We argue that the PES did not play a key role in encouraging the establishment and development of parties in the CEE states from the 2004 enlargement in the early stages of accession. We contend that the overall influence of party federations has been limited, and that these limitations were as much in evidence before enlargement took place as they were afterwards.

134 Analysis of the role of small GTP binding protein Rab in intracellular melanosome transport

1996 ◽  
Vol 12 (2) ◽  
pp. 204
Author(s):  
K. Araki ◽  
T. Horikawa ◽  
K. Nakagawa ◽  
Y. Funasaka ◽  
M. Ichihashi
Keyword(s):  
Binding Protein ◽  
Gtp Binding Protein ◽  
Gtp Binding

The role of digital artefacts in early stages of distributed innovation processes

2021 ◽  
Vol 50 (10) ◽  
pp. 104349
Author(s):  
Markus C. Becker ◽  
Francesco Rullani ◽  
Francesco Zirpoli
Keyword(s):  
Early Stages ◽  
Innovation Processes

scholarly journals A Gnotobiotic Model to Examine Plant and Microbiome Contributions to Survival under Arsenic Stress

2020 ◽  
Vol 9 (1) ◽  
pp. 45
Author(s):  
María del Carmen Molina ◽  
James F. White ◽  
Sara García-Salgado ◽  
M. Ángeles Quijano ◽  
Natalia González-Benítez
Keyword(s):  
Seedling Growth ◽  
Endophytic Bacteria ◽  
Root Hairs ◽  
Resistant Bacteria ◽  
Relative Importance ◽  
Early Stages ◽  
Bacterial Interaction ◽  
Arsenic Stress ◽  
Free Media

So far, the relative importance of the plant and its microbiome in the development of early stages of plant seedling growth under arsenic stress has not been studied. To test the role of endophytic bacteria in increasing plant success under arsenic stress, gnotobiotic seeds of J. montana were inoculated with two endophytic bacteria: Pantoea conspicua MC-K1 (PGPB and As resistant bacteria) and Arthrobacter sp. MC-D3A (non-helper and non-As resistant bacteria) and an endobacteria mixture. In holobiotic seedlings (with seed-vectored microbes intact), neither the capacity of germination nor development of roots and lateral hairs was affected at 125 μM As(V). However, in gnotobiotic seedlings, the plants are negatively impacted by absence of a microbiome and presence of arsenic, resulting in reduced growth of roots and root hairs. The inoculation of a single PGPB (P. conspicua-MCK1) shows a tendency to the recovery of the plant, both in arsenic enriched and arsenic-free media, while the inoculation with Arthrobacter sp. does not help in the recovery of the plants. Inoculation with a bacterial mixture allows recovery of plants in arsenic free media; however, plants did not recover under arsenic stress, probably because of a bacterial interaction in the mixture.

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