Structural and biochemical characterization of cauliflower mosaic virus reverse transcriptase.

Reverse transcriptases (RTs) are enzymes with DNA polymerase and RNase H activities. They convert ssRNA into dsDNA and are key enzymes for the replication of retroviruses and retroelements. Caulimoviridae is a major family of plant-infecting viruses.

Structure-Based Discovery of High-Affinity Small Molecule Ligands and Development of Tool Probes to Study the Role of Chitinase-3-Like Protein 1.

Chitinase-3-like-1 (CHI3L1), also known as YKL-40, is a glycoprotein linked to inflammation, fibrosis, and cancer. This study explored CHI3L1's interactions with various oligosaccharides using microscale thermophoresis (MST) and AlphaScreen (AS). These investigations guided the development of high-throughput screening assays to assess interference of small molecules in binding between CHI3L1 and biotinylated small molecules or heparan sulfate-based probes.

Structure of human TRPM8 channel.

TRPM8 is a non-selective cation channel permeable to both monovalent and divalent cations that is activated by multiple factors, such as temperature, voltage, pressure, and changes in osmolality. It is a therapeutic target for anticancer drug development, and its modulators can be utilized for several pathological conditions. Here, we present a cryo-electron microscopy structure of a human TRPM8 channel in the closed state that was solved at 2.

Morphology and immunohistochemical characteristics of the otic ganglion in the chinchilla (Chinchilla laniger Molina).

Introduction: The available literature provides relatively little information on the morphology of the autonomic head ganglia in rodents including their neurochemical codding.

Material And Methods: Morphological investigations of the otic ganglion of the chinchilla were performed using the modified acetylcholinesterase method. The cellular structure was investigated with histological techniques and neurochemical properties were studied with the double-labelling immunofluorescence method.

The right coronary artery in the heart of chinchilla (Chinchilla laniger Molina).

The pattern of normal coronary vascularization in a mammalian heart includes the presence of both right and left coronary arteries. According to the literature data, the presence of single major coronary arteries is mainly related to cardiac abnormalities. Previously it has been reported that the right coronary artery is absent in the coronary vascularization of the heart in the chinchilla.

Distribution and neurochemical characteristic of the cardiac nerve structures in the heart of chinchilla (Chinchilla laniger Molina).

Introduction: The heart innervation is made up of plexo-ganglionic formation containing sympathetic, parasympathetic, and sensory components. We examined the distribution and neurochemical coding of the ganglia and nerve fibers in the chinchilla's heart.

Material And Methods: The heart sections of 10 male and 10 female adult chinchillas were processed in accordance with the thiocholine method for acetylcholine esterase (AChE), and the SPG method for detecting the presence of adrenergic fibers was applied.

Structures of Substrate Complexes of Foamy Viral Protease-Reverse Transcriptase.

Reverse transcriptases (RTs) use their DNA polymerase and RNase H activities to catalyze the conversion of single-stranded RNA to double-stranded DNA (dsDNA), a crucial process for the replication of retroviruses. Foamy viruses (FVs) possess a unique RT, which is a fusion with the protease (PR) domain. The mechanism of substrate binding by this enzyme has been unknown.

Cholinergic and adrenergic innervation of the pancreas in chinchilla (Chinchilla Laniger Molina).

Introduction: Cholinergic and adrenergic innervation of the pancreas in chinchilla (Chinchilla Laniger Molina) was examined in this study. The pancreas is both an exocrine and endocrine gland with autonomic and sensory innervation presented by the numerous nerve fibers and small agglomerations of nerve cells.

Material And Methods: Investigations were performed on 16 adult chinchillas of both sexes.

Structural bases of peptidoglycan recognition by lysostaphin SH3b domain.

Staphylococcus simulans lysostaphin cleaves pentaglycine cross-bridges between stem peptides in the peptidoglycan of susceptible staphylococci, including S. aureus. This enzyme consists of an N-terminal catalytic domain and a cell wall binding domain (SH3b), which anchors the protein to peptidoglycan.

5'-Phosphorothiolate Dinucleotide Cap Analogues: Reagents for Messenger RNA Modification and Potent Small-Molecular Inhibitors of Decapping Enzymes.

The 5' cap consists of 7-methylguanosine (mG) linked by a 5'-5'-triphosphate bridge to messenger RNA (mRNA) and acts as the master regulator of mRNA turnover and translation initiation in eukaryotes. Cap analogues that influence mRNA translation and turnover (either as small molecules or as part of an RNA transcript) are valuable tools for studying gene expression, which is often also of therapeutic relevance. Here, we synthesized a series of 15 dinucleotide cap (mGpppG) analogues containing a 5'-phosphorothiolate (5'-PSL) moiety (i.

Structural analysis of mtEXO mitochondrial RNA degradosome reveals tight coupling of nuclease and helicase components.

Nuclease and helicase activities play pivotal roles in various aspects of RNA processing and degradation. These two activities are often present in multi-subunit complexes from nucleic acid metabolism. In the mitochondrial exoribonuclease complex (mtEXO) both enzymatic activities are tightly coupled making it an excellent minimal system to study helicase-exoribonuclease coordination.

The siRNA suppressor RTL1 is redox-regulated through glutathionylation of a conserved cysteine in the double-stranded-RNA-binding domain.

RNase III enzymes cleave double stranded (ds)RNA. This is an essential step for regulating the processing of mRNA, rRNA, snoRNA and other small RNAs, including siRNA and miRNA. Arabidopsis thaliana encodes nine RNase III: four DICER-LIKE (DCL) and five RNASE THREE LIKE (RTL).

mRNA cap analogues substituted in the tetraphosphate chain with CX2: identification of O-to-CCl2 as the first bridging modification that confers resistance to decapping without impairing translation.

Analogues of the mRNA 5'-cap are useful tools for studying mRNA translation and degradation, with emerging potential applications in novel therapeutic interventions including gene therapy. We report the synthesis of novel mono- and dinucleotide cap analogues containing dihalogenmethylenebisphosphonate moiety (i.e.

Polycyclic aromatic hydrocarbons connected with Schiff base linkers: Experimental and theoretical photophysical characterization and electrochemical properties.

A series of polyaromatic hydrocarbons with anthracene, phenanthrene and pyrene units connected with Schiff base junctions were synthesized via condensation of p-phenylenediamine and hydrazine with selected aldehydes. The effect of both hydrocarbon structures and presence of N-N- or phenyl- linked diimines on properties of the prepared azines and azomethines was analyzed. The obtained compounds were soluble in common organic solvents and melted in the range of 226-317°C.

New anthracene-based Schiff bases: Theoretical and experimental investigations of photophysical and electrochemical properties.

The new Schiff bases bearing anthracene unit were synthesized from 2-aminoanthracene and various aldehydes such as: benzaldehyde, 4-(diphenylamino)benzaldehyde, 9-phenanthrenecarboxaldehyde, 9-anthracenecarboxaldehyde, and biphenyl-4-carboxaldehyde, 2-naphthaldehyde. Resulted azomethines were characterized by IR, NMR (H and C), elemental analysis and UV-vis spectroscopy. The imine consists of anthracene and biphenyl moieties exhibited liquid crystal properties and their nematic phase showed Schlieren texture.

Functional and evolutionary analyses of Helicobacter pylori HP0231 (DsbK) protein with strong oxidative and chaperone activity characterized by a highly diverged dimerization domain.

Helicobacter pylori does not encode the classical DsbA/DsbB oxidoreductases that are crucial for oxidative folding of extracytoplasmic proteins. Instead, this microorganism encodes an untypical two proteins playing a role in disulfide bond formation - periplasmic HP0231, which structure resembles that of EcDsbC/DsbG, and its redox partner, a membrane protein HpDsbI (HP0595) with a β-propeller structure. The aim of presented work was to assess relations between HP0231 structure and function.

Helicobacter pylori HP0377, a member of the Dsb family, is an untypical multifunctional CcmG that cooperates with dimeric thioldisulfide oxidase HP0231.

Background: In the genome of H. pylori 26695, 149 proteins containing the CXXC motif characteristic of thioldisulfide oxidoreductases have been identified to date. However, only two of these proteins have a thioredoxin-like fold (i.

Morphology and Topography of the Celiac Plexus in Degu (Octodon Degus).

Here, we investigate the morphology and topography of the celiac plexus components in degu (Octodon degus). The study was performed using six adult individuals of both sexes. Macromorphological observations were performed using a derivative of the thiocholine method specially adapted for this study type (Gienc, 1977).

Crystal structure of the catalytic core of Rad2: insights into the mechanism of substrate binding.

Rad2/XPG belongs to the flap nuclease family and is responsible for a key step of the eukaryotic nucleotide excision DNA repair (NER) pathway. To elucidate the mechanism of DNA binding by Rad2/XPG, we solved crystal structures of the catalytic core of Rad2 in complex with a substrate. Rad2 utilizes three structural modules for recognition of the double-stranded portion of DNA substrate, particularly a Rad2-specific α-helix for binding the cleaved strand.

Ty3 reverse transcriptase complexed with an RNA-DNA hybrid shows structural and functional asymmetry.

Retrotransposons are a class of mobile genetic elements that replicate by converting their single-stranded RNA intermediate to double-stranded DNA through the combined DNA polymerase and ribonuclease H (RNase H) activities of the element-encoded reverse transcriptase (RT). Although a wealth of structural information is available for lentiviral and gammaretroviral RTs, equivalent studies on counterpart enzymes of long terminal repeat (LTR)-containing retrotransposons, from which they are evolutionarily derived, is lacking. In this study, we report the first crystal structure of a complex of RT from the Saccharomyces cerevisiae LTR retrotransposon Ty3 in the presence of its polypurine tract-containing RNA-DNA hybrid.

Organisation of autonomic nervous structures in the large intestine of chinchilla (Chinchilla laniger Molina).

The organization of autonomic nerve structures in the large intestine of chinchilla was investigated using histochemical and immunocytochemical methods. The myenteric plexus formed network nodes of cholinergic neurocyte agglomerations connected with bundles of nerve fibres and localized between the circular and longitudinal layers of the smooth muscles. The highest density of myenteric plexus was observed in the rectum.

Organization of the innervation of the oesophagus and stomach in chinchilla (Chinchilla laniger, Molina).

Using the histochemical and histological techniques the morphology and topography of the autonomic plexuses of the oesophagus and stomach in chinchilla (Chinchilla laniger) was investigated. AChE-positive and adrenergic structures in the myenteric and submucosal plexus were observed. According to the results the cholinergic structures were formed by the different in shape network meshes, various size of the neurons agglomerations and nerve fibres.

Structural analysis of monomeric retroviral reverse transcriptase in complex with an RNA/DNA hybrid.

A key step in proliferation of retroviruses is the conversion of their RNA genome to double-stranded DNA, a process catalysed by multifunctional reverse transcriptases (RTs). Dimeric and monomeric RTs have been described, the latter exemplified by the enzyme of Moloney murine leukaemia virus. However, structural information is lacking that describes the substrate binding mechanism for a monomeric RT.