Expression of concern: Valence tautomeric interconversion of bis-dioxolene cobalt complex with imino-pyridine functionalized by TEMPO moiety in solid solutions with isostructural nickel analogue: phase transitions and monocrystal destruction.

Expression of concern for 'Valence tautomeric interconversion of bis-dioxolene cobalt complex with imino-pyridine functionalized by TEMPO moiety in solid solutions with isostructural nickel analogue: phase transitions and monocrystal destruction' by Michael P. Bubnov , , 2024, , 9151-9160, https://doi.org/10.

Valence tautomeric interconversion of bis-dioxolene cobalt complex with imino-pyridine functionalized by TEMPO moiety in solid solutions with isostructural nickel analogue: phase transitions and monocrystal destruction.

Valence tautomeric complexes (VT) are promising systems for creating molecular devices. From this viewpoint, valence tautomeric complexes with a hysteresis loop on the magnetic curve are of special interest as potential memory elements. The hysteresis loop is a consequence of retarded structural rearrangements which investigation is an actual problem.

Valence tautomeric transition of bis(o-dioxolene) cobalt complex in solid state and solution.

Valence tautomer transition occurs mainly in 3d metalorganic complexes with redox-active ligands and makes them potential candidates for single-molecular switches. The transition occurs under temperature, pressure, or light-induced stimuli and is strongly affected by the intermolecular interactions. However single-crystal x-ray diffraction is not always applicable to such systems when crystal structure is destroyed upon transition or system is studied in the solution.

[Experimental work: reconstruction of the pelvi-ureteric junction and ureter using testicular tunica vaginalis autograft].

Aim: To evaluate the results of surgical reconstruction of the upper urinary tract using an autograft of testicular tunica vaginalis in experimental animals.

Materials And Methods: The article presents the results of partial replacement of the renal pelvis and ureter with an autograft in 25 male dogs. The grafts were harvested by resection of the parietal layer of the testicular tunica vaginalis, which was transplanted into the region of the pelvi-ureteric junction and the proximal ureter.

Valence-Tautomeric Interconversion in a Bis(dioxolene)cobalt Complex with Iminopyridine Functionalized by a TEMPO Moiety. Phase Transition Coupled with Monocrystal Destruction.

Iminopyridine modified by TEMPO nitroxide was utilized for the synthesis of an octahedral bis(o-semiquinonato)cobalt complex. Variable-temperature magnetic susceptibility measurements detect a valence tautomeric transformation in the temperature range 200-300 K. A reproducible hysteresis loop of about 40 K width is observed on the magnetic moment temperature dependence in the transition region.

[A 20-year prospective follow-up study to evaluate the development of retinopathy and nephropathy after the onset of type 1 diabetes mellitus: Contribution of glycemic control and metabolic memory].

Aim: To assess the time course of changes in the level of glycated hemoglobin (HbA1c) for 20 years after the onset of type 1 diabetes mellitus (T1DM) and to compare its correlation with the development of microvascular complications, such as diabetic retinopathy (DR) and diabetic nephropathy (DN).

Subjects And Methods: A total of 187 children with new-onset T1DM were registered in Moscow in 1994. During the 20-year follow-up study, these patients underwent regular check-ups at the Endocrinology Research Center, Ministry of Health of the Russian Federation, which included assessment of physical data, HbA1c 2-4 times a year, biochemical blood and albuminuria tests (once per year), and ophthalmologic examination (twice a year).

Thickness determination of graphene on metal substrate by reflection spectroscopy.

We show that reflectivity measurements enable the determination of the thickness of multilayered graphene on a metal substrate. The developed technique is based on comparison of the substrate reflectance with and without graphene and relies on the strong absorbance of graphene and high refractive index contrast. We demonstrate the technique by measuring the thickness of the CVD graphene film grown on a copper substrate.

The RNA transport element of the murine musD retrotransposon requires long-range intramolecular interactions for function.

Retrovirus replication requires specialized transport mechanisms to export genomic mRNA from the nucleus to the cytoplasm of the infected cell. This regulation is mediated by a combination of viral and/or cellular factors that interact with cis-acting RNA export elements linking the viral RNA to the cellular CRM1 or NXF1 nuclear export pathways. Endogenous type D murine LTR retrotransposons (musD) were reported to contain an RNA export element located upstream of the 3'-LTR.

Alternative transcripts expressed by small bristles, the Drosophila melanogaster nxf1 gene.

The tissue-specific accumulation of small bristles (Dm nxf1) transcripts at different developmental stages of Drosophila melanogaster was analyzed by Northern blots and RT PCR. We identified four distinct transcripts: ubiquitous (3.5kb); ovary and early embryo specific (3.

Nuclear export factor RBM15 facilitates the access of DBP5 to mRNA.

The conserved mRNA export receptor NXF1 (Mex67 in yeast) assembles with messenger ribonucleoproteins (mRNP) in the nucleus and guides them through the nuclear pore complex into the cytoplasm. The DEAD family RNA helicase Dbp5 is essential for nuclear export of mRNA and is thought to dissociate Mex67 from mRNP upon translocation, thereby generating directional passage. However, the molecular mechanism by which Dbp5 recognizes Mex67-containing mRNP is not clear.

Secretion and biological activity of short signal peptide IL-15 is chaperoned by IL-15 receptor alpha in vivo.

The two known isoforms of IL-15 contain either a long signal peptide (LSP) or a short signal peptide (SSP), and are produced by alternatively spliced transcripts. It has been proposed that SSP IL-15 remains exclusively intracellular, and its function is unclear. In this study, we show that, similar to LSP IL-15, the SSP IL-15 is stabilized and secreted efficiently upon coexpression of IL-15Ralpha.

The RNA-binding motif protein 15B (RBM15B/OTT3) acts as cofactor of the nuclear export receptor NXF1.

The human SPEN family proteins SHARP, RBM15/OTT1, and RBM15B/OTT3 share the structural domain architecture but show distinct functional properties. Here, we examined the function of OTT3 and compared it with its paralogues RBM15 and SHARP. We found that OTT3, like RBM15, has post-transcriptional regulatory activity, whereas SHARP does not, supporting a divergent role of RBM15 and OTT3.

The RNA transport element RTE is essential for IAP LTR-retrotransposon mobility.

We previously identified an RNA transport element (RTE) present at a high copy number in the mouse genome. Here, we show that a related element, RTE-D, is part of a mobile LTR-retrotransposon, which belongs to a family of intracisternal A-particle related elements (IAP). We demonstrate that RTE-D is essential for the mobility of the retrotransposon and it can be substituted by other known RNA export signals.

RNA-binding motif protein 15 binds to the RNA transport element RTE and provides a direct link to the NXF1 export pathway.

Retroviruses/retroelements provide tools enabling the identification and dissection of basic steps for post-transcriptional regulation of cellular mRNAs. The RNA transport element (RTE) identified in mouse retrotransposons is functionally equivalent to constitutive transport element of Type D retroviruses, yet does not bind directly to the mRNA export receptor NXF1. Here, we report that the RNA-binding motif protein 15 (RBM15) recognizes RTE directly and specifically in vitro and stimulates export and expression of RTE-containing reporter mRNAs in vivo.

RTE and CTE mRNA export elements synergistically increase expression of unstable, Rev-dependent HIV and SIV mRNAs.

Studies of retroviral mRNA export identified two distinct RNA export elements utilizing conserved eukaryotic mRNA export mechanism(s), namely the Constitutive Transport Element (CTE) and the RNA Transport Element (RTE). Although RTE and CTE are potent in nucleocytoplasmic mRNA transport and expression, neither element is as powerful as the Rev-RRE posttranscriptional control. Here, we found that whereas CTE and the up-regulatory mutant RTEm26 alone increase expression from a subgenomic gag and env clones, the combination of these elements led to a several hundred-fold, synergistic increase.

Identification and characterization of the mouse nuclear export factor (Nxf) family members.

TAP/hNXF1 is a key factor that mediates general cellular mRNA export from the nucleus, and its orthologs are structurally and functionally conserved from yeast to humans. Metazoans encode additional proteins that share homology and domain organization with TAP/hNXF1, suggesting their participation in mRNA metabolism; however, the precise role(s) of these proteins is not well understood. Here, we found that the human mRNA export factor hNXF2 is specifically expressed in the brain, suggesting a brain-specific role in mRNA metabolism.

Nuclear export factor family protein participates in cytoplasmic mRNA trafficking.

In eukaryotes, the nuclear export of mRNA is mediated by nuclear export factor 1 (NXF1) receptors. Metazoans encode additional NXF1-related proteins of unknown function, which share homology and domain organization with NXF1. Some mammalian NXF1-related genes are expressed preferentially in the brain and are thought to participate in neuronal mRNA metabolism.

Structural and functional analysis of the RNA transport element, a member of an extensive family present in the mouse genome.

We previously identified an RNA transport element (RTE), present in a subclass of rodent intracisternal A particle retroelements (F. Nappi, R. Schneider, A.

PSF acts through the human immunodeficiency virus type 1 mRNA instability elements to regulate virus expression.

Human immunodeficiency virus type 1 (HIV) gag/pol and env mRNAs contain cis-acting regulatory elements (INS) that impair stability, nucleocytoplasmic transport, and translation by unknown mechanisms. This downregulation can be counteracted by the viral Rev protein, resulting in efficient export and expression of these mRNAs. Here, we show that the INS region in HIV-1 gag mRNA is a high-affinity ligand of p54nrb/PSF, a heterodimeric transcription/splicing factor.

U2AF participates in the binding of TAP (NXF1) to mRNA.

TAP/NXF1 is a conserved mRNA export receptor serving as a link between messenger ribonucleoproteins (mRNPs) and the nuclear pore complex. The mechanism by which TAP recognizes its export substrate is unclear. We show here that TAP is added to spliced mRNP in human cells.

Retroviral constitutive transport element evolved from cellular TAP(NXF1)-binding sequences.

The constitutive transport element (CTE) of type D retroviruses serves as a signal of nuclear export of unspliced viral RNAs. The human TAP(NXF1) protein, a cellular mRNA export factor, directly binds to CTE and mediates nuclear export of CTE-containing RNAs. Here, we use genomic SELEX (systematic evolution of ligands by exponential enrichment) to show that the human genome encodes a family of high-affinity TAP ligands.

Identification of a novel posttranscriptional regulatory element by using a rev- and RRE-mutated human immunodeficiency virus type 1 DNA proviral clone as a molecular trap.

Human immunodeficiency virus (HIV) and all other lentiviruses utilize the essential viral protein Rev, which binds to RRE RNA, to export their unspliced and partially spliced mRNAs from the nucleus. We used a rev- and RRE-defective HIV type 1 (HIV-1) molecular clone in complementation experiments to establish a method for the rapid isolation of posttranscriptional regulatory elements from the mammalian genome by selecting for rescue of virus replication. Viruses rescued by this method contained a novel element with homology to rodent intracisternal A-particle (IAP) retroelements.

The mRNA export in Caenorhabditis elegans is mediated by Ce-NXF-1, an ortholog of human TAP/NXF and Saccharomyces cerevisiae Mex67p.

Human TAP and Saccharomyces cerevisiae Mex67p belong to a family of proteins that mediate mRNA export. Computer searches identified previously two Caenorhabditis elegans genes, C15H11.3 and C115H11.

Identification of novel import and export signals of human TAP, the protein that binds to the constitutive transport element of the type D retrovirus mRNAs.

The nuclear export of the unspliced type D retrovirus mRNA depends on the cis-acting constitutive transport RNA element (CTE) that has been shown to interact with the human TAP (hTAP) protein promoting the export of the CTE-containing mRNAs. We report here that hTAP is a 619-amino-acid protein extending the previously identified protein by another 60 residues at the N terminus and that hTAP shares high homology with the predicted rat and mouse TAP proteins. We found that hTAP is a nuclear protein that accumulates in the nuclear rim and the nucleoplasm.