The Extended “Two-Barrel” Polymerases Superfamily: Structure, Function and Evolution

Publication date: 20 September 2019Source: Journal of Molecular Biology, Volume 431, Issue 20Author(s): Ludovic SauguetAbstractDNA and RNA polymerases (DNAP and RNAP) play central roles in genome replication, maintenance and repair, as well as in the expression of genes through their transcription. Multisubunit RNAPs carry out transcription and are represented, without exception, in all cellular life forms as well as in nucleo-cytoplasmic DNA viruses. Since their discovery, multisubunit RNAPs have been the focus of intense structural and functional studies revealing that they all share a well-conserved active-site region called the two-barrel catalytic core. The two-barrel core hosts the polymerase active site, which is located at the interface between two double-psi β-barrel domains that contribute distinct amino acid residues to the active site in an asymmetrical fashion. Recently, sequencing and structural studies have added a surprising variety of DNA and RNA to the two-barrel superfamily, including the archaeal replicative DNAP (PolD), which extends the family to DNA-dependent DNAPs involved in replication. While all these polymerases share a minimal core that must have been present in their common ancestor, the two-barrel polymerase superfamily now encompasses a remarkable diversity of enzymes, including DNA-dependent RNAPs, RNA-dependent RNAPs, and DNA-dependent DNAPs, which participate in critical biological processes such as DNA transcription, DNA replication, a...
Source: Journal of Molecular Biology - Category: Molecular Biology Source Type: research

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CONCLUSIONS Radiation can induce vasogenic edema and is associated with the RBI occurrence and development. VEGF protein is highly relevant to the induction of edema and thrombosis in the acute phase of RBI and in the early delayed phase of RBI, including vascular repair and regeneration, thrombus ablation and other events. Human recombinant endostatin can reduce the progression of cerebral edema during the early onset of RBI. PMID: 31816619 [PubMed - in process]
Source: Medical Science Monitor - Category: Research Tags: Med Sci Monit Source Type: research
CONCLUSIONS: Reported complication rates associated with femoral VCD implantation are low. However, in some cases VCD implantation may account for severe complications including limb losses. Therefore, an adequate patient selection is necessary to detect those cases at higher risk for complications. PMID: 31814376 [PubMed - as supplied by publisher]
Source: International Angiology - Category: Cardiology Tags: Int Angiol Source Type: research
The purpose of this study was to assess whether the lower exercise tolerance in children after coarctation repair is associated with alterations in peripheral tissue oxygenation during exercise. A total of 16 children after coarctation repair and 20 healthy control subjects performed an incremental ramp exercise test to exhaustion. Cerebral and locomotor muscle oxygenation were measured by means of near infrared spectroscopy. The responses of cerebral and muscle tissue oxygenation index (cTOI, mTOI), oxygenated (O2Hb), and deoxygenated hemoglobin (HHb) as a function of work rate were compared. Correlations between residual...
Source: Frontiers in Physiology - Category: Physiology Source Type: research
Animal and human pathogens of the genus Bordetella are not commonly considered to be intracellular pathogens, although members of the closely related classical bordetellae are known to enter and persist within macrophages in vitro and have anecdotally been reported to be intracellular in clinical samples. B. bronchiseptica, the species closest to the ancestral lineage of the classical bordetellae, infects a wide range of mammals but is known to have an alternate life cycle, persisting, replicating and disseminating with amoeba. These observations give rise to the hypothesis that the ability for intracellular survival has a...
Source: Frontiers in Microbiology - Category: Microbiology Source Type: research
Innate lymphoid cells (ILCs) are a group of immune cells that are important for defense against pathogens, tissue repair, and lymphoid organogenesis. They share similar characteristics with various subsets of helper T cells but lack specific antigen receptors. Interleukin-7 (IL-7) and thymic stromal lymphopoietin (TSLP) are cytokines that engage the IL-7Rα and have major roles in dictating the fate of ILCs. Recent advances in the field have revealed transcriptional programs associated with ILC development and function. In this article, we will review recent studies of the role of IL-7 and TSLP in ILC development and ...
Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
Conclusion: In comparison to desensitising-only, desensitising/whitening toothpastes neither accounted for increased surface loss nor impaired tubule occlusion of root dentine.
Source: Oral health and Preventive dentistry - Category: Dentistry Source Type: research
Publication date: 9 December 2019Source: Cancer Cell, Volume 36, Issue 6Author(s): Jianhui Ma, Jorge A. Benitez, Jie Li, Shunichiro Miki, Claudio Ponte de Albuquerque, Thais Galatro, Laura Orellana, Ciro Zanca, Rachel Reed, Antonia Boyer, Tomoyuki Koga, Nissi M. Varki, Tim R. Fenton, Suely Kazue Nagahashi Marie, Erik Lindahl, Timothy C. Gahman, Andrew K. Shiau, Huilin Zhou, John DeGroot, Erik P. Sulman
Source: Cancer Cell - Category: Cancer & Oncology Source Type: research
Authors: Sun L, Liu W, Zhang LJ Abstract As the key defense molecules originally identified in Drosophila, Toll-like receptor (TLR) superfamily members play a fundamental role in detecting invading pathogens or damage and initiating the innate immune system of mammalian cells. The skin, the largest organ of the human body, protects the human body by providing a critical physical and immunological active multilayered barrier against invading pathogens and environmental factors. At the first line of defense, the skin is constantly exposed to pathogen-associated molecular patterns (PAMPs) and damage-associated molecul...
Source: Journal of Immunology Research - Category: Allergy & Immunology Tags: J Immunol Res Source Type: research
This study was performed to determine if strain can supplement the ability of left ventricular ejection fraction (LVEF) to predict post-op ventricular dysfunction in patients undergoing mitral valve (MV) surgery for degenerative mitral regurgitation (DMR).MethodsFrom 2004 to 2017, 520 patients with an LVEF> 60% underwent MV surgery (98% repair) for DMR. All patients had preoperative (pre-op), pre-discharge (pre-dsg) and follow-up (F/U) (mean 5.0±3.6 years) echocardiograms. Speckle tracking was performed in 119/520 (22.9%) patients to determine LV strain, right ventricular (RV) free-wall strain, and left atrial lo...
Source: The Annals of Thoracic Surgery - Category: Cardiovascular & Thoracic Surgery Source Type: research
Condition:   Incisional Hernia Interventions:   Procedure: Laparoscopic incisional ventral hernia repair;   Procedure: Open incisional ventral hernia repair Sponsor:   Salvador Peiro Active, not recruiting
Source: - Category: Research Source Type: clinical trials
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