Translational Control in Eukaryotic Organisms

1973 ◽  
pp. 251-256 ◽  
Author(s):  
William A. Strycharz ◽  
Marjut Ranki ◽  
Kjeld A. Marcker
Keyword(s):  
Translational Control ◽  
Eukaryotic Organisms

Molecular cloning of a centrin homolog from Marsilea vestita and evidence for its translational control during spermiogenesis

1999 ◽  
Vol 77 (2) ◽  
pp. 101-108 ◽  
Author(s):  
Peter E Hart ◽  
Stephen M Wolniak
Keyword(s):  
Translational Control ◽  
De Novo ◽  
Basal Bodies ◽  
Motile Cells ◽  
Marsilea Vestita ◽  
Stored Mrna ◽  
Eukaryotic Organisms ◽  
Alpha Amanitin ◽  
Made In

Spermiogenesis in the water fern Marsilea vestita is a process that reaches completion 11 h after dry microspores are immersed in an aqueous medium at 20°C. Each microspore produces 32 spermatozoids and each spermatozoid has a coiled cell body and approximately 140 cilia. The spermatids make basal bodies de novo, from a structure known as a blepharoplast. From the onset of development, the spores contain a large quantity of protein and stored mRNA. We have found previously that centrin, a protein involved in the function of microtubule organizing centers and present in association with basal bodies in motile cells, is made in large quantity approximately 4 h after the microspores are placed into liquid medium. In this paper, we show that a centrin cDNA (MvCen1) we isolated from M. vestita closely resembles centrin cDNAs from other eukaryotic organisms. MvCen1, synthesized in Escherichia coli as a GST-fusion protein, reacted with anti-centrin monoclonal antibodies on immunoblots. Northern blot analysis demonstrates that centrin mRNA is present in the dry microspore at the time of imbibition, at levels that remain constant over 10 h of development and are unaffected by treatment of spores with alpha-amanitin. The centrin transcripts, stored in dry microspores, cannot be translated in vitro for at least 30 min after imbibition.Key words: Marsilea vestita, spermatozoid, spermiogenesis, centrin, MTOC.

E3 ubiquitin ligases

2005 ◽  
Vol 41 ◽  
pp. 15-30 ◽  
Author(s):  
Helen C. Ardley ◽  
Philip A. Robinson
Keyword(s):  
Protein Complexes ◽  
Loss Of Function ◽  
Direct Role ◽  
Cellular Processes ◽  
Substrate Protein ◽  
Protein Ubiquitination ◽  
C Terminus ◽  
Full Complement ◽  
Spatio Temporal ◽  
Eukaryotic Organisms

The selectivity of the ubiquitin–26 S proteasome system (UPS) for a particular substrate protein relies on the interaction between a ubiquitin-conjugating enzyme (E2, of which a cell contains relatively few) and a ubiquitin–protein ligase (E3, of which there are possibly hundreds). Post-translational modifications of the protein substrate, such as phosphorylation or hydroxylation, are often required prior to its selection. In this way, the precise spatio-temporal targeting and degradation of a given substrate can be achieved. The E3s are a large, diverse group of proteins, characterized by one of several defining motifs. These include a HECT (homologous to E6-associated protein C-terminus), RING (really interesting new gene) or U-box (a modified RING motif without the full complement of Zn2+-binding ligands) domain. Whereas HECT E3s have a direct role in catalysis during ubiquitination, RING and U-box E3s facilitate protein ubiquitination. These latter two E3 types act as adaptor-like molecules. They bring an E2 and a substrate into sufficiently close proximity to promote the substrate's ubiquitination. Although many RING-type E3s, such as MDM2 (murine double minute clone 2 oncoprotein) and c-Cbl, can apparently act alone, others are found as components of much larger multi-protein complexes, such as the anaphase-promoting complex. Taken together, these multifaceted properties and interactions enable E3s to provide a powerful, and specific, mechanism for protein clearance within all cells of eukaryotic organisms. The importance of E3s is highlighted by the number of normal cellular processes they regulate, and the number of diseases associated with their loss of function or inappropriate targeting.

The role of DUBs in the post-translational control of cell migration

2019 ◽  
Vol 63 (5) ◽  
pp. 579-594 ◽  
Author(s):  
Guillem Lambies ◽  
Antonio García de Herreros ◽  
Víctor M. Díaz
Keyword(s):  
Cell Migration ◽  
Translational Control ◽  
Epithelial To Mesenchymal Transition ◽  
Extracellular Matrix Remodeling ◽  
Matrix Remodeling ◽  
Mesenchymal Transition ◽  
Tgfβ Receptors ◽  
Fundamental Process ◽  
Multistep Process

Abstract Cell migration is a multifactorial/multistep process that requires the concerted action of growth and transcriptional factors, motor proteins, extracellular matrix remodeling and proteases. In this review, we focus on the role of transcription factors modulating Epithelial-to-Mesenchymal Transition (EMT-TFs), a fundamental process supporting both physiological and pathological cell migration. These EMT-TFs (Snail1/2, Twist1/2 and Zeb1/2) are labile proteins which should be stabilized to initiate EMT and provide full migratory and invasive properties. We present here a family of enzymes, the deubiquitinases (DUBs) which have a crucial role in counteracting polyubiquitination and proteasomal degradation of EMT-TFs after their induction by TGFβ, inflammatory cytokines and hypoxia. We also describe the DUBs promoting the stabilization of Smads, TGFβ receptors and other key proteins involved in transduction pathways controlling EMT.

Translational Control during Early Development

1997 ◽  
Vol 7 (1-2) ◽  
pp. 73-94 ◽  
Author(s):  
Barbara Stebbins-Boaz ◽  
Joel D. Richter
Keyword(s):  
Early Development ◽  
Translational Control

ANTICYTOKINE ACTIVITY OF THE PROTOZOA BLASTOCYSTIS SPP

2020 ◽  
pp. 44-48
Author(s):  
Bugero N.V. ◽  
Ilyina N.A. ◽  
Aleksandrova S.M.
Keyword(s):  
Gastrointestinal Tract ◽  
Gastrointestinal Diseases ◽  
Control Group ◽  
Ulcer Disease ◽  
Cytokine Balance ◽  
High Prevalence ◽  
Blastocystis Spp ◽  
High Level ◽  
Eukaryotic Organisms ◽  
High Degree

In addition to the classical pathogens, which are well understood and well identified, new pathogens with the potential to spread epidemiologically are being identified. Some of these little-known organisms are the simplest Blastocystis spp. blastocystostosis. The clinical significance of Blastocystis spp. and its pathogenicity are still under discussion. This parasite belongs to a group of single-celled eukaryotic organisms living in the colon of the human intestine. Blastocystis spp. is known to be found both in people with reduced immune status and in individuals without any clinical manifestation. It has been established that a sufficiently high degree of invasiveness is observed in persons with gastrointestinal tract diseases, dermatosis, allergic reactions, in patients with carriers of the human immunodeficiency virus, etc. Possessing persistence factors, protozoa blastocysts contribute to the inactivation of host defensive mechanisms, providing a stable anthogonistic effect. In recent years, many works have been devoted to the characteristics of the persistent properties of Blastocystis spr., however, individual properties of blastocysts, in particular, anticytokine activity (ACA), have not yet been studied. In this regard, the work studied the anticytokine activity of microorganisms isolated from healthy subjects and patients with gastrointestinal tract diseases. A high prevalence of the studied characteristic in the subjects was shown. The expression of anticytokine activity in the obtained isolates of blastocysts was the highest in the group of persons with gastric ulcer disease, which decreased in the order of duodenal ulcer, chronic cholecystitis, chronic gastritis, etc. The data obtained in this work on the high level of ACA expression in blastocyst isolates obtained from individuals with gastrointestinal diseases as compared with the control group enables to conclude that their exometabolites may influence the local cytokine balance [1], which supports the inflammatory process.

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