Total synthesis, stereochemical assignment, and biological evaluation of opantimycin A and analogues thereof.

Opantimycin A, a rare antimycin-class antibiotic without the macrolide core, was isolated from sp. RK88-1355 in 2017. In this study, we explored the total synthesis and stereochemical assignment of opantimycin A.

Chimera RNA transcribed from integrated HPV18 genome with adjacent host genomic region promotes oncogenic gene expression through condensate formation.

Most cervical cancers are caused by human papillomavirus (HPV) infection. In HeLa cells, the HPV18 viral genome is integrated at chromosome 8q24.21 and activates transcription of the proto-oncogene c-Myc.

MED26-containing Mediator may orchestrate multiple transcription processes through organization of nuclear bodies.

Mediator is a coregulatory complex that plays essential roles in multiple processes of transcription regulation. One of the human Mediator subunits, MED26, has a role in recruitment of the super elongation complex (SEC) to polyadenylated genes and little elongation complex (LEC) to non-polyadenylated genes, including small nuclear RNAs (snRNAs) and replication-dependent histone (RDH) genes. MED26-containing Mediator plays a role in 3' Pol II pausing at the proximal region of transcript end sites in RDH genes through recruitment of Cajal bodies (CBs) to histone locus bodies (HLBs).

La(III)-Catalysed degradation of polyesters to monomers transesterifications.

Tris(acetylacetonato)lanthanum(III) (1 mol%) catalyses the degradation of poly(butylene succinate) ( = 90 700) by transesterification in MeOH at 90 °C for 4 h, thus affording dimethyl succinate (>99% yield) and 1,4-butanediol (98% yield). Moreover, the quantitative degradations of poly(ethylene adipate), poly(ethylene terephthalate) and poly(butylene terephthalate) are also reported.

Dual function of SF3B2 on chromatin and RNA to regulate transcription in head and neck squamous cell carcinoma.

RNA is spliced concomitantly with transcription and the process is organized by RNA splicing factors, transcriptional regulators, and chromatin regulators. RNA is spliced in close proximity to transcription machinery. Hence, some RNA splicing factors may play a role in transcription.

The 3' Pol II pausing at replication-dependent histone genes is regulated by Mediator through Cajal bodies' association with histone locus bodies.

Non-polyadenylated mRNAs of replication-dependent histones (RDHs) are synthesized by RNA polymerase II (Pol II) at histone locus bodies (HLBs). HLBs frequently associate with Cajal bodies (CBs), in which 3'-end processing factors for RDH genes are enriched; however, this association's role in transcription termination of RDH genes remains unclear. Here, we show that Pol II pauses immediately upstream of transcript end sites of RDH genes and Mediator plays a role in this Pol II pausing through CBs' association with HLBs.

Digold(I) Thianthrenyl Complexes. Effect of Diphosphine Ligands on Molecular Structures in the Solid State and in Solution.

A series of digold complexes possessing two thianthrenyl ligands, Au(Thi)(PhP(CH) PPh) (Thi: 1-thianthrenyl; : = 1, : = 2, : = 3, : = 4), were prepared and characterized by crystallographic and spectroscopic measurements. X-ray crystallography of complexes and revealed U-shaped structures with short Au-Au distances [3.2171(3) Å and 3.

A Macrocyclic Gold(I)-Biphenylene Complex: Triangular Molecular Structure with Twisted Au (diphosphine) Corners and Reductive Elimination of [6]Cycloparaphenylene.

The digold(I) complex [Au Cl (Cy PCH PCy )] reacts with 4,4'-diphenylene diboronic acid to form a triangular macrocyclic complex with twisted Au-P-C-P-Au groups at the three corners. The synthesis of the complex and its chemical oxidation produced [6]cycloparaphenylene ([6]CPP) in 59 % overall yield.

The role of Mediator and Little Elongation Complex in transcription termination.

Mediator is a coregulatory complex that regulates transcription of Pol II-dependent genes. Previously, we showed that human Mediator subunit MED26 plays a role in the recruitment of Super Elongation Complex (SEC) or Little Elongation Complex (LEC) to regulate the expression of certain genes. MED26 plays a role in recruiting SEC to protein-coding genes including c-myc and LEC to small nuclear RNA (snRNA) genes.

Gain-of-Function MN1 Truncation Variants Cause a Recognizable Syndrome with Craniofacial and Brain Abnormalities.

MN1 was originally identified as a tumor-suppressor gene. Knockout mouse studies have suggested that Mn1 is associated with craniofacial development. However, no MN1-related phenotypes have been established in humans.

Total Syntheses and Configuration Assignments of JBIR-06 and Related Depsipeptides.

The first total syntheses of JBIR-06 and two analogous depsipeptides, 12-membered antimycin-class antibiotics, have been accomplished via Shiina macrolactonization. Comparison of the spectroscopic data of the synthesized compounds with those reported for natural products verified that the absolute configutation of the natural products was (2 S,4 S,6 S,7 R,14 S).

Association between third molar agenesis patterns and agenesis of other teeth in a Japanese orthodontic population.

The purpose of this study was to investigate the patterns of third molar agenesis and incidence of agenesis of other permanent teeth in a Japanese orthodontic patient group. A total of 417 Japanese subjects (134 males and 283 females) with agenesis of one or more third molars were divided into four groups according to the agenesis pattern, and 874 other Japanese subjects (302 males and 572 females) without third molar agenesis were assigned to a control group. Panoramic radiographs and medical and dental records were used to examine for tooth agenesis.

Bidirectional binding property of high glycine-tyrosine keratin-associated protein contributes to the mechanical strength and shape of hair.

Since their first finding in wool 50years ago, keratin-associated proteins (KAPs), which are classified into three groups; high sulfur (HS) KAPs, ultra high sulfur (UHS) KAPs, and high glycine-tyrosine (HGT) KAPs, have been the target of curiosity for scientists due to their characteristic amino acid sequences. While HS and UHS KAPs are known to function in disulfide bond crosslinking, the function of HGT KAPs remains unknown. To clarify the function as well as the binding partners of HGT KAPs, we prepared KAP8.

Initial shear bond strength of orthodontic brackets bonded to bleached teeth with a self-etching adhesive system.

Objectives: To examine the initial shear bond strength of orthodontic brackets bonded to bleached teeth with a self-etching adhesive system, as well as the effect of the length of time after bleaching on the initial bond strength.

Method And Materials: Ninety premolars were collected and divided equally among a control group (CG) of unbleached teeth with brackets bonded, an immediate group (IG) with teeth bonded soon after bleaching, and a delayed group (DG) consisting of teeth bleached and then immersed in artificial saliva for 7 days before bracket bonding. Subsequently, the teeth of each group were equally assigned to two different primer adhesive systems: the acid-etch-and-rinse adhesive system (35% phosphoric acid gel and Transbond XT primer) and the self-etching adhesive system (Transbond Plus self-etching primer).

Mapping ultra-weak protein-protein interactions between heme transporters of Staphylococcus aureus.

Iron is an essential nutrient for the proliferation of Staphylococcus aureus during bacterial infections. The iron-regulated surface determinant (Isd) system of S. aureus transports and metabolizes iron porphyrin (heme) captured from the host organism.

Catalytic activity of MsbA reconstituted in nanodisc particles is modulated by remote interactions with the bilayer.

ATP-binding cassette (ABC) transporters couple hydrolysis of ATP with vectorial transport across the cell membrane. We have reconstituted ABC transporter MsbA in nanodiscs of various sizes and lipid compositions to test whether ATPase activity is modulated by the properties of the bilayer. ATP hydrolysis rates, Michaelis-Menten parameters, and dissociation constants of substrate analog ATP-γ-S demonstrated that physicochemical properties of the bilayer modulated binding and ATPase activity.

Stepwise characterization of the thermodynamics of trichocyte intermediate filament protein supramolecular assembly.

Trichocyte intermediate filament protein (IFP) is a heterodimeric complex that plays a pivotal role in the hair shaft for its mechanical strength, hair shape, and so on. Trichocyte IFP consists of acidic-type IFP and basic-type IFP, and the well-studied supramolecular assembly process of the complex occurs via the following steps: dimer formation, tetramer formation, formation of the lateral 32mer, and the elongation of the 32mer. Among these interactions, only the dimer formation, owing to coiled-coil interaction, has been described in detail; the nature of other interactions remains unspecified.

Effects of tooth bleaching on shear bond strength of brackets rebonded with a self-etching adhesive system.

The purpose of this study was to ascertain the effects of tooth bleaching on the shear bond strength of orthodontic brackets rebonded with a self-etching adhesive system. A total of 39 premolars were collected and divided into three equal groups: in group 1 bracket bonding was performed without bleaching treatment; specimens in group 2 were bonded immediately after bleaching; and group 3 teeth were bleached, then immersed in artificial saliva and left for 7 days before bonding. The shear bond strength was measured, with the bonding/debonding procedures repeated once after the first debonding, and the bracket/adhesive failure modes were evaluated by the adhesive remnant index after each debonding.

Maxillary first molar agenesis and other dental anomalies.

Objective: To explore the association of maxillary first molar agenesis with other dental anomalies in Japanese orthodontic patients.

Materials And Methods: A total of 32 subjects with one or two congenitally missing maxillary first molars (group M) were selected and divided into group 1M (12 subjects with one maxillary first molar missing) and group 2M (20 subjects with two maxillary first molars missing). As controls, 32 sex-matched subjects without agenesis of maxillary first molars were collected (group C).

Solubilization of membrane proteins with novel N-acylamino acid detergents.

N-Acylamino acids are a new family of versatile biological surfactants capable of extracting integral membrane proteins of various topologies from the biological membrane, in many instances surpassing the efficiency of commercial detergents.

Non-denaturing solubilization of inclusion bodies.

It has been a conventional notion that cytoplasmic recombinant expression leads to either soluble protein or inclusion bodies. In the latter case, it was always assumed that proteins in inclusion bodies (IBs) are more or less unfolded and hence require complete denaturing condition for solubilization, which uses strong detergents, urea or guanidine hydrochloride. However, we often observe distribution of expressed proteins in both soluble and insoluble fractions.

Cephalometric evaluation of maxillary sinus sizes in different malocclusion classes.

We found few studies on the association between maxillary sinus size and malocclusion in an electronic search using PubMed. The purpose of this study was to investigate maxillary sinus size in different malocclusion groups and the association between maxillary sinus size and dentofacial morphology by the use of lateral cephalometric radiographs. A total of 120 lateral cephalograms were used.

Utilization of Arg-elution method for FLAG-tag based chromatography.

FLAG-tag is one of the commonly used purification technologies for recombinant proteins. An antibody, M2, specifically binds to the FLAG-tag whether it is attached to N- or C-terminus of proteins to be purified. The bound proteins are generally eluted by competition with a large excess of free FLAG peptide.

Immobilized metal affinity chromatography in the presence of arginine.

Arginine hydrochloride (ArgHCl) is a versatile solvent additive, as it suppresses protein aggregation. ArgHCl has been used for protein refolding and to solubilize proteins from loose inclusion bodies. Immobilized metal affinity chromatography (IMAC) is one of the most commonly used technologies for purification of recombinant proteins.