Capture-and-release of a sulfoquinovose-binding protein on sulfoquinovose-modified agarose.

The solute-binding protein (SBP) components of periplasmic binding protein-dependent ATP-binding cassette (ABC)-type transporters often possess exquisite selectivity for their cognate ligands. Maltose binding protein (MBP), the best studied of these SBPs, has been extensively used as a fusion partner to enable the affinity purification of recombinant proteins. However, other SBPs and SBP-ligand based affinity systems remain underexplored. The sulfoquinovose-binding protein SmoF, is a substrate-binding protein component of the ABC transporter cassette in Agrobacterium tumefaciens involved in importing sulfoquinovose (SQ) and its derivatives for SQ catabolism. Here, we show that SmoF binds with high affinity to the octyl glycoside of SQ (octyl-SQ), demonstrating remarkable tolerance to extension of the anomeric substituent. The 3D X-ray structure of the SmoF·octyl-SQ complex reveals accommodation of the octyl chain, which projects to the protein surface, providing impetus for the synthesis of a linker-equipped SQ-amine using a thiol-ene reaction as a key step, and its conjugation to cyanogen bromide modified agarose. We demonstrate the successful capture and release of SmoF from SQ-agarose resin using SQ as competitive eluant, and selectivity for release versus other organosulfonates. We show that SmoF can be captured and purified from a cell lysate, demonstrating the utility of SQ-agarose in capturing SQ binding proteins from complex mixtures. The present work provides a pathway for development of 'capture-and-release' affinity resins for the discovery and study of SBPs.

Structural basis of dimerization and nucleic acid binding of human DBHS proteins NONO and PSPC1.

The Drosophila behaviour/human splicing (DBHS) proteins are a family of RNA/DNA binding cofactors liable for a range of cellular processes. DBHS proteins include the non-POU domain-containing octamer-binding protein (NONO) and paraspeckle protein component 1 (PSPC1), proteins capable of forming combinatorial dimers. Here, we describe the crystal structures of the human NONO and PSPC1 homodimers, representing uncharacterized DBHS dimerization states. The structures reveal a set of conserved contacts and structural plasticity within the dimerization interface that provide a rationale for dimer selectivity between DBHS paralogues. In addition, solution X-ray scattering and accompanying biochemical experiments describe a mechanism of cooperative RNA recognition by the NONO homodimer. Nucleic acid binding is reliant on RRM1, and appears to be affected by the orientation of RRM1, influenced by a newly identified 'ß-clasp' structure. Our structures shed light on the molecular determinants for DBHS homo- and heterodimerization and provide a basis for understanding how DBHS proteins cooperatively recognize a broad spectrum of RNA targets.

Paraspeckle subnuclear bodies depend on dynamic heterodimerisation of DBHS RNA-binding proteins via their structured domains.

RNA-binding proteins of the DBHS (Drosophila Behavior Human Splicing) family, NONO, SFPQ, and PSPC1 have numerous roles in genome stability and transcriptional and posttranscriptional regulation. Critical to DBHS activity is their recruitment to distinct subnuclear locations, for example, paraspeckle condensates, where DBHS proteins bind to the long noncoding RNA NEAT1 in the first essential step in paraspeckle formation. To carry out their diverse roles, DBHS proteins form homodimers and heterodimers, but how this dimerization influences DBHS localization and function is unknown. Here, we present an inducible GFP-NONO stable cell line and use it for live-cell 3D-structured illumination microscopy, revealing paraspeckles with dynamic, twisted elongated structures. Using siRNA knockdowns, we show these labeled paraspeckles consist of GFP-NONO/endogenous SFPQ dimers and that GFP-NONO localization to paraspeckles depends on endogenous SFPQ. Using purified proteins, we confirm that partner swapping between NONO and SFPQ occurs readily in vitro. Crystallographic analysis of the NONO-SFPQ heterodimer reveals conformational differences to the other DBHS dimer structures, which may contribute to partner preference, RNA specificity, and subnuclear localization. Thus overall, our study suggests heterodimer partner availability is crucial for NONO subnuclear distribution and helps explain the complexity of both DBHS protein and paraspeckle dynamics through imaging and structural approaches.

Derrone Targeting the TGF Type 1 Receptor Kinase Improves Bleomycin-Mediated Pulmonary Fibrosis through Inhibition of Smad Signaling Pathway.

Transforming growth factor-ß (TGF-ß) has a strong impact on the pathogenesis of pulmonary fibrosis. Therefore, in this study, we investigated whether derrone promotes anti-fibrotic effects on TGF-ß1-stimulated MRC-5 lung fibroblast cells and bleomycin-induced lung fibrosis. Long-term treatment with high concentrations of derrone increased the cytotoxicity of MRC-5 cells; however, substantial cell death was not observed at low concentrations of derrone (below 0.05 µg/mL) during a three-day treatment. In addition, derrone significantly decreased the expressions of TGF-ß1, fibronectin, elastin, and collagen1α1, and these decreases were accompanied by downregulation of α-SMA expression in TGF-ß1-stimulated MRC-5 cells. Severe fibrotic histopathological changes in infiltration, alveolar congestion, and alveolar wall thickness were observed in bleomycin-treated mice; however, derrone supplementation significantly reduced these histological deformations. In addition, intratracheal administration of bleomycin resulted in lung collagen accumulation and high expression of α-SMA and fibrotic genes-including TGF-ß1, fibronectin, elastin, and collagen1α1-in the lungs. However, fibrotic severity in intranasal derrone-administrated mice was significantly less than that of bleomycin-administered mice. Molecular docking predicted that derrone potently fits into the ATP-binding pocket of the TGF-ß receptor type 1 kinase domain with stronger binding scores than ATP. Additionally, derrone inhibited TGF-ß1-induced phosphorylation and nuclear translocations of Smad2/3. Overall, derrone significantly attenuated TGF-ß1-stimulated lung inflammation in vitro and bleomycin-induced lung fibrosis in a murine model, indicating that derrone may be a promising candidate for preventing pulmonary fibrosis.

Colwellia maritima sp. nov. and Polaribacter marinus sp. nov., isolated from seawater.

Two Gram-stain-negative, catalase- and oxidase-positive, and aerobic bacteria, strains MSW7T and MSW13T, were isolated from seawater. Cells of strains MSW7T and MSW13T are motile and non-motile rods, respectively. Strain MSW7T optimally grew at 25 °C and pH 7.0 and in the presence of 3 % (w/v) NaCl, whereas strain MSW13T optimally grew at 25 °C and pH 6.0-7.0 and in the presence of 2 % NaCl. As the sole respiratory quinone and the major fatty acids and polar lipids, strain MSW7T contained ubiquinone-8, C16 : 0, C15 : 1 ω8c, C17 : 1 ω8c and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), and phosphatidylethanolamine and phosphatidylglycerol, respectively, whereas strain MSW13T contained menaquinone-6, C15 : 1 ω6c, iso-C15 : 0, anteiso-C15 : 0, and iso-C15 : 0 3-OH, and phosphatidylethanolamine, respectively. The DNA G+C contents of strains MSW7T and MSW13T were 37.3 and 29.9 %, respectively. Phylogenetic analyses based on 16S rRNA gene sequences showed that strains MSW7T and MSW13T were most closely related to Colwellia echini A3T and Polaribacter atrinae WP25T with 98.8 and 98.1 % sequence similarities, respectively. The average nucleotide identity and digital DNA-DNA hybridization values between strain MSW7T and C. echini A3T and between strain MSW13T and P. atrinae KACC 17473T were 73.6 and 22.6 % and 80.4 and 23.8 %, respectively. Based on phenotypic, chemotaxonomic and phylogenetic data, strains MSW7T and MSW13T represent novel species of the genera Colwellia and Polaribacter, respectively, for which the names Colwellia maritima sp. nov. and Polaribacter marinus sp. nov. are proposed, respectively. The type strains of C. maritima sp. nov. and P. marinus sp. nov. are MSW7T (=KACC 22339T=JCM 35001T) and MSW13T (=KACC 22341T=JCM 35021T), respectively.

Structural basis of the zinc-induced cytoplasmic aggregation of the RNA-binding protein SFPQ.

SFPQ is a ubiquitous nuclear RNA-binding protein implicated in many aspects of RNA biogenesis. Importantly, nuclear depletion and cytoplasmic accumulation of SFPQ has been linked to neuropathological conditions such as Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS). Here, we describe a molecular mechanism by which SFPQ is mislocalized to the cytoplasm. We report an unexpected discovery of the infinite polymerization of SFPQ that is induced by zinc binding to the protein. The crystal structure of human SFPQ in complex with zinc at 1.94 Å resolution reveals intermolecular interactions between SFPQ molecules that are mediated by zinc. As anticipated from the crystal structure, the application of zinc to primary cortical neurons induced the cytoplasmic accumulation and aggregation of SFPQ. Mutagenesis of the three zinc-coordinating histidine residues resulted in a significant reduction in the zinc-binding affinity of SFPQ in solution and the zinc-induced cytoplasmic aggregation of SFPQ in cultured neurons. Taken together, we propose that dysregulation of zinc availability and/or localization in neuronal cells may represent a mechanism for the imbalance in the nucleocytoplasmic distribution of SFPQ, which is an emerging hallmark of neurodegenerative diseases including AD and ALS.

Rapid purification method for human SFPQ by implementing zinc-induced polymerization.

Splicing factor proline- and glutamine-rich (SFPQ) is an RNA-binding protein, playing significant roles in gene regulation and subnuclear body formation. Our recent serendipitous discovery showed that SFPQ binds zinc directly and forms an infinite polymer that is induced by zinc binding to the protein. The zinc-induced reversible polymerization has led us to exploit this property to develop a rapid purification strategy for SFPQ without the use of affinity tags. In combination with the variation of ionic strength for salting-out of SFPQ, the reversible zinc-induced precipitation of SFPQ reduced the purification time required to obtain pure SFPQ to a single day. The purified protein was subjected to the previously reported crystallization condition. The resulting crystals diffracted to 2.22 Å resolution, confirming the quality of SFPQ purified with this new rapid purification strategy.

The Emerging Role of the RNA-Binding Protein SFPQ in Neuronal Function and Neurodegeneration.

RNA-binding proteins (RBPs) are a class of proteins known for their diverse roles in RNA biogenesis, from regulating transcriptional processes in the nucleus to facilitating translation in the cytoplasm. With higher demand for RNA metabolism in the nervous system, RBP misregulation has been linked to a wide range of neurological and neurodegenerative diseases. One of the emerging RBPs implicated in neuronal function and neurodegeneration is splicing factor proline- and glutamine-rich (SFPQ). SFPQ is a ubiquitous and abundant RBP that plays multiple regulatory roles in the nucleus such as paraspeckle formation, DNA damage repair, and various transcriptional regulation processes. An increasing number of studies have demonstrated the nuclear and also cytoplasmic roles of SFPQ in neurons, particularly in post-transcriptional regulation and RNA granule formation. Not surprisingly, the misregulation of SFPQ has been linked to pathological features shown by other neurodegenerative disease-associated RBPs such as aberrant RNA splicing, cytoplasmic mislocalization, and aggregation. In this review, we discuss recent findings on the roles of SFPQ with a particular focus on those in neuronal development and homeostasis as well as its implications in neurodegenerative diseases.

Crystal structure of a SFPQ/PSPC1 heterodimer provides insights into preferential heterodimerization of human DBHS family proteins.

Members of the Drosophila behavior human splicing (DBHS) protein family are nuclear proteins implicated in many layers of nuclear functions, including RNA biogenesis as well as DNA repair. Definitive of the DBHS protein family, the conserved DBHS domain provides a dimerization platform that is critical for the structural integrity and function of these proteins. The three human DBHS proteins, splicing factor proline- and glutamine-rich (SFPQ), paraspeckle component 1 (PSPC1), and non-POU domain-containing octamer-binding protein (NONO), form either homo- or heterodimers; however, the relative affinity and mechanistic details of preferential heterodimerization are yet to be deciphered. Here we report the crystal structure of a SFPQ/PSPC1 heterodimer to 2.3-Å resolution and analyzed the subtle structural differences between the SFPQ/PSPC1 heterodimer and the previously characterized SFPQ homodimer. Analytical ultracentrifugation to estimate the dimerization equilibrium of the SFPQ-containing dimers revealed that the SFPQ-containing dimers dissociate at low micromolar concentrations and that the heterodimers have higher affinities than the homodimer. Moreover, we observed that the apparent dissociation constant for the SFPQ/PSPC1 heterodimer was over 6-fold lower than that of the SFPQ/NONO heterodimer. We propose that these differences in dimerization affinity may represent a potential mechanism by which PSPC1 at a lower relative cellular abundance can outcompete NONO to heterodimerize with SFPQ.

The central active site arginine in sulfite oxidizing enzymes alters kinetic properties by controlling electron transfer and redox interactions.

A central conserved arginine, first identified as a clinical mutation leading to sulfite oxidase deficiency, is essential for catalytic competency of sulfite oxidizing molybdoenzymes, but the molecular basis for its effects on turnover and substrate affinity have not been fully elucidated. We have used a bacterial sulfite dehydrogenase, SorT, which lacks an internal heme group, but transfers electrons to an external, electron accepting cytochrome, SorU, to investigate the molecular functions of this arginine residue (Arg78). Assay of the SorT Mo centre catalytic competency in the absence of SorU showed that substitutions in the central arginine (R78Q, R78K and R78M mutations) only moderately altered SorT catalytic properties, except for R78M which caused significant reduction in SorT activity. The substitutions also altered the Mo-centre redox potentials (MoVI/V potential lowered by ca. 60-80mV). However, all Arg78 mutations significantly impaired the ability of SorT to transfer electrons to SorU, where activities were reduced 17 to 46-fold compared to SorTWT, precluding determination of kinetic parameters. This was accompanied by the observation of conformational changes in both the introduced Gln and Lys residues in the crystal structure of the enzymes. Taking into account data collected by others on related SOE mutations we propose that the formation and maintenance of an electron transfer complex between the Mo centre and electron accepting heme groups is the main function of the central arginine, and that the reduced turnover and increases in KMsulfite are caused by the inefficient operation of the oxidative half reaction of the catalytic cycle in enzymes carrying these mutations.

Uliginosibacterium sangjuense sp. nov., isolated from sediment of the Nakdong River.

A Gram-negative, aerobic, motile by flagella, and light yellow bacterium, designated SS1-76T, was isolated from sediment of the Nakdong River in Sangju-si, Republic of Korea. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate SS1-76T belongs to the genus Uliginosibacterium of the family Rhodocyclaceae, exhibiting high sequence similarity with the type strains of Uliginosibacterium gangwonense 5YN10-9T (96.0%) and Uliginosibacterium paludis KBP-13T (94.9%). Strain SS1-76T contains ubiquinone-8 as a respiratory quinone and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), C16:0, and C14:0 as major fatty acids. The cellular polar lipids are composed of phosphatidylethanolamine, phosphatidylglycerol, and unidentified aminophospholipids. The DNA G+C content was 65.3 mol%. Phenotypic, chemotaxonomic, and phylogenetic evidence clearly indicated that strain SS1-76T represents a novel species of the genus Uliginosibacterium, for which the name Uliginosibacterium sangjuense sp. nov. is proposed. The type strain is SS1-76T (= KCTC 52159T = JCM 31375T).

Perlucidibaca aquatica sp. nov., isolated from fresh water.

A Gram-staining-negative, non-motile, non-pigmented, strictly aerobic and rod-shape bacterium, designated BK296T, was isolated from stream water originating from a limestone cave in Samcheok, Korea. Optimal growth of strain BK296T was observed at 30 °C, pH 7.0-8.0 and without NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain BK296T belonged to the genus Perlucidibaca, forming a robust clade with a member of the genus, and was most closely related to Perlucidibaca piscinae (97.8 %). The average nucleotide identity value between strain BK296T and Perlucidibacapiscinae IMCC1704T was 79.8 %, and the genome-to-genome distance was 17.5 % on mean. The G+C content of the DNA of strain BK296T was 55.7 mol%. The major fatty acids were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0, C12 : 0 3-OH and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). The major isoprenoid quinone was ubiquinone Q-8. On the basis of phenotypic, genotypic and phylogenetic analyses, strain BK296T (=KCTC 52162T=JCM 31377T) represents a novel species of the genus Perlucidibaca, for which the name Perlucidibaca aquatica sp. nov. is proposed.

Lacibacter nakdongensis sp. nov., isolated from river sediment.

A novel Gram-stain-negative, non-spore-forming, orange-pigmented bacterium, designated strain SS2-56T, was isolated from sediment of the Nakdong River in Sangju-si, Republic of Korea. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate SS2-56T belongs to the family Chitinophagaceae, and was most closely related to Lacibacter daechungensis H32-4T (96.6 % similarity) and Lacibacter cauensis NJ-8T (96.1 %). Strain SS2-56T contained menaquinone 7 (MK-7) as a respiratory quinone and iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 1 G, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0 as major fatty acids. The major polar lipids of strain SS2-56T were phosphatidylethanolamine, one unidentified aminophospholipid and four unidentified lipids. The DNA G+C content was 43.8 mol%. Phenotypic, chemotaxonomic and phylogenetic evidence clearly indicates that strain SS2-56T represents a novel species of the genus Lacibacter, for which the name Lacibacter nakdongensis sp. nov. is proposed. The type strain is SS2-56T (=KCTC 52160T=JCM 31372T).

The structure of human SFPQ reveals a coiled-coil mediated polymer essential for functional aggregation in gene regulation.

SFPQ, (a.k.a. PSF), is a human tumor suppressor protein that regulates many important functions in the cell nucleus including coordination of long non-coding RNA molecules into nuclear bodies. Here we describe the first crystal structures of Splicing Factor Proline and Glutamine Rich (SFPQ), revealing structural similarity to the related PSPC1/NONO heterodimer and a strikingly extended structure (over 265 Å long) formed by an unusual anti-parallel coiled-coil that results in an infinite linear polymer of SFPQ dimers within the crystals. Small-angle X-ray scattering and transmission electron microscopy experiments show that polymerization is reversible in solution and can be templated by DNA. We demonstrate that the ability to polymerize is essential for the cellular functions of SFPQ: disruptive mutation of the coiled-coil interaction motif results in SFPQ mislocalization, reduced formation of nuclear bodies, abrogated molecular interactions and deficient transcriptional regulation. The coiled-coil interaction motif thus provides a molecular explanation for the functional aggregation of SFPQ that directs its role in regulating many aspects of cellular nucleic acid metabolism.

Genetic and functional characterization of an extracellular modular GH6 endo-ß-1,4-glucanase from an earthworm symbiont, Cellulosimicrobium funkei HY-13.

The gene (1608-bp) encoding a GH6 endo-ß-1,4-glucanase (CelL) from the earthworm-symbiotic bacterium Cellulosimicrobium funkei HY-13 was cloned from its whole genome sequence, expressed recombinantly, and biochemically characterized. CelL (56.0 kDa) is a modular enzyme consisting of an N-terminal catalytic GH6 domain (from Val57 to Pro396), which is 71 % identical to a GH6 protein (accession no.: WP_034662937) from Cellulomonas sp. KRMCY2, together with a C-terminal CBM 2 domain (from Cys429 to Cys532). The highest catalytic activity of CelL toward carboxymethylcellulose (CMC) was observed at 50 °C and pH 5.0, and was relatively stable at a broad pH range of 4.0-10.0. The enzyme was capable of efficiently hydrolyzing the cellulosic polymers in the order of barley ß-1,3-1,4-D-glucan > CMC > lichenan > Avicel > konjac glucomannan. However, cellobiose, cellotriose, p-nitrophenyl derivatives of mono- and disaccharides, or structurally unrelated carbohydrate polymers including ß-1,3-D-glucan, ß-1,4-D-galactomannan, and ß-1,4-D-xylan were not susceptible to CelL. The enzymatic hydrolysis of cellopentaose resulted in the production of a mixture of 68.6 % cellobiose and 31.4 % cellotriose but barley ß-1,3-1,4-D-glucan was 100 % degraded to cellotriose by CelL. The enzyme strongly bound to Avicel, ivory nut mannan, and chitin but showed relatively weak binding affinity to lichenan, lignin, or poly(3-hydroxybutyrate) granules.

The design and structural characterization of a synthetic pentatricopeptide repeat protein.

Proteins of the pentatricopeptide repeat (PPR) superfamily are characterized by tandem arrays of a degenerate 35-amino-acid α-hairpin motif. PPR proteins are typically single-stranded RNA-binding proteins with essential roles in organelle biogenesis, RNA editing and mRNA maturation. A modular, predictable code for sequence-specific binding of RNA by PPR proteins has recently been revealed, which opens the door to the de novo design of bespoke proteins with specific RNA targets, with widespread biotechnological potential. Here, the design and production of a synthetic PPR protein based on a consensus sequence and the determination of its crystal structure to 2.2 Šresolution are described. The crystal structure displays helical disorder, resulting in electron density representing an infinite superhelical PPR protein. A structural comparison with related tetratricopeptide repeat (TPR) proteins, and with native PPR proteins, reveals key roles for conserved residues in directing the structure and function of PPR proteins. The designed proteins have high solubility and thermal stability, and can form long tracts of PPR repeats. Thus, consensus-sequence synthetic PPR proteins could provide a suitable backbone for the design of bespoke RNA-binding proteins with the potential for high specificity.

The crystal structure of a homodimeric Pseudomonas glyoxalase†I enzyme reveals asymmetric metallation commensurate with half-of-sites activity.

The Zn inactive class of glyoxalase I (Glo1) metalloenzymes are typically homodimeric with two metal-dependent active sites. While the two active sites share identical amino acid composition, this class of enzyme is optimally active with only one metal per homodimer. We have determined the X-ray crystal structure of GloA2, a Zn inactive Glo1 enzyme from Pseudomonas aeruginosa. The presented structures exhibit an unprecedented metal-binding arrangement consistent with half-of-sites activity: one active site contains a single activating Ni(2+) ion, whereas the other contains two inactivating Zn(2+) ions. Enzymological experiments prompted by the binuclear Zn(2+) site identified a novel catalytic property of GloA2. The enzyme can function as a Zn(2+) /Co(2+) -dependent hydrolase, in addition to its previously determined glyoxalase I activity. The presented findings demonstrate that GloA2 can accommodate two distinct metal-binding arrangements simultaneously, each of which catalyzes a different reaction.

Phaeobacter marinintestinus sp. nov., isolated from the intestine of a sea cucumber (Apostichopus japonicus).

A Gram-negative, strictly aerobic, non-motile, and rod-shaped bacterial strain designated UB-M7(T) was isolated from the intestine of a sea cucumber (Apostichopus japonicus) collected from Pohang in South Korea. Strain UB-M7(T) displayed optimal growth at 25 °C, pH 7.0-7.5, and with 2.0-3.0 % (w/v) NaCl. Phylogenetic analyses based on the 16S rRNA gene sequences showed that strain UB-M7(T) clustered with Phaeobacter arcticus DSM 23566(T), Phaeobacter inhibens DSM 16374(T), Phaeobacter gallaeciensis BS107(T), and Phaeobacter leonis 306(T), exhibiting 16S rRNA gene sequence similarity values of 96.8, 96.6, 96.4, and 96.2 %, respectively. Strain UB-M7(T) was found to exhibit the highest gyrB sequence similarity value of 80.6 % to the type strain of P. arcticus. The major respiratory quinone of strain UB-M7(T) was found to be ubiquinone 10 (Q-10). The major cellular fatty acids (>5 % of the total fatty acids) are summed features 8 (comprising C18:1 ω7c and/or C18:1 ω6c), 11-methyl C18:1 ω7c, and cyclo C19:0 ω8c. The DNA G+C content was found to be 58.5 mol% and DNA-DNA relatedness value with P. arcticus JCM 14644(T) was 17.2 ± 2.4 %. The major polar lipids of strain UB-M7(T) were identified as phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine; one phospholipid, and three other lipids remain unidentified. Based on its phenotypic, phylogenetic, and chemotaxonomic properties it is concluded that strain UB-M7(T) represents a novel species in the genus Phaeobacter, for which the name Phaeobacter marinintestinus sp. nov. is proposed. The type strain is UB-M7(T) (=KCCM 43045(T) = JCM 19926(T)).

Structure of the heterodimer of human NONO and paraspeckle protein component 1 and analysis of its role in subnuclear body formation.

Proteins of the Drosophila behavior/human splicing (DBHS) family include mammalian SFPQ (PSF), NONO (p54nrb), PSPC1, and invertebrate NONA and Hrp65. DBHS proteins are predominately nuclear, and are involved in transcriptional and posttranscriptional gene regulatory functions as well as DNA repair. DBHS proteins influence a wide gamut of biological processes, including the regulation of circadian rhythm, carcinogenesis, and progression of cancer. Additionally, mammalian DBHS proteins associate with the architectural long noncoding RNA NEAT1 (Menε/ß) to form paraspeckles, subnuclear bodies that alter gene expression via the nuclear retention of RNA. Here we describe the crystal structure of the heterodimer of the multidomain conserved region of the DBHS proteins, PSPC1 and NONO. These proteins form an extensively intertwined dimer, consistent with the observation that the different DBHS proteins are typically copurified from mammalian cells, and suggesting that they act as obligate heterodimers. The PSPC1/NONO heterodimer has a right-handed antiparallel coiled-coil that positions two of four RNA recognition motif domains in an unprecedented arrangement on either side of a 20-Å channel. This configuration is supported by a protein:protein interaction involving the NONA/paraspeckle domain, which is characteristic of the DBHS family. By examining various mutants and truncations in cell culture, we find that DBHS proteins require an additional antiparallel coiled-coil emanating from either end of the dimer for paraspeckle subnuclear body formation. These results suggest that paraspeckles may potentially form through self-association of DBHS dimers into higher-order structures.

Effect of Ampelopsis Radix on wound healing in scalded rats.

BACKGROUND: Ampelopsis Radix has been used as a traditional Korean medicine for the treatment of burns and scalds. However, there has been no scientific research to date on the wound healing properties of Ampelopsis Radix for scald burns. This study aimed to evaluate the healing effect of Ampelopsis japonica root tuber ethanol extract (AJE) on induced cutaneous scald injury in Sprague Dawley (SD) rats. METHODS: Hot water scalds were induced in SD rats, who were then divided into the following 5 groups; 1) control group without treatment, 2) positive control group with 1% Silver sulfadiazine (SSD), 3) Vaseline group, and groups 4) and 5) that used Vaseline containing 5% and 20% AJE, respectively. The ointment was applied topically to the experimental rats, once daily for 21 days, starting at 24 h post induction of the scald injury. Gross examination, measurement of wound size, and histopathological examination were performed. And quantitative measurement of cytokine levels of tumor necrosis factor alpha (TNF-α), interleukin-10 (IL-10), transforming growth factor beta 1 (TGF-ß1), and vascular endothelial growth factor (VEGF) were performed by enzyme-linked immunosorbent assay. RESULTS: Clinical evaluation showed that the AJE and Vaseline groups, rapidly desquamated scab on day 12 post-scalding; in particular, the 20% AJE group achieved the greatest extent of skin recovery. Sizes of scald wound were significantly lower on days 12, 15, 18, and 21 in the AJE treated groups compared to the control groups. Histopathological evaluation showed a well-organized epithelial layer, angiogenesis, tissue granulation and collagen formation with the exception of inflammatory cells in the AJE-treated groups compared to the control groups on day 14, indicating that tissue regeneration had occurred. AJE treatment decreased TNF-α and increased IL-10 levels on days 2 and 14, indicating the anti-inflammatory action of AJE. The AJE groups also showed a decrease in TGF-ß1 levels on day 7 and VEGF on day 14 in the serum of scald inflicted SD rat model. CONCLUSIONS: These results suggest that AJE possesses scald wound healing activity via accelerating the scald wound repair during the inflammation and proliferative phases of the healing process.