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Although recent research progress on the abundant C-to-U RNA editing events in plant chloroplasts and mitochondria has uncovered many recognition factors and their molecular mechanisms, the intrinsic regulation of RNA editing within plants remains largely unknown. This study aimed to establish a regulatory relationship in Arabidopsis between the plant hormone auxin and chloroplast RNA editing. We first analyzed auxin response elements (AuxREs) present within promoters of chloroplast editing factors reported to date. We found that each has more than one AuxRE, suggesting a potential regulatory role of auxin in their expression. Further investigation unveiled that the depletion of auxin synthesis gene YUC2 reduces the expression of several editing factors. However, in yuc2 mutants, only the expression of CRR4, DYW1, ISE2, and ECD1 editing factors and the editing efficiency of their corresponding editing sites, ndhD-2 and rps14-149, were simultaneously suppressed. In addition, exogenous IAA and the overexpression of YUC2 enhanced the expression of these editing factors and the editing efficiency at the ndhD-2 and rps14-149 sites. These results suggested a direct effect of auxin upon the editing of the ndhD-2 and rps14-149 sites through the modulation of the expression of the editing factors. We further demonstrated that ARF1, a downstream transcription factor in the auxin-signaling pathway, could directly bind to and inactivate the promoters of CRR4, DYW1, and ISE2 in a dual-luciferase reporter system, thereby inhibiting their expression. Moreover, the overexpression of ARF1 in Arabidopsis significantly reduced the expression of the three editing factors and the editing efficiency at the ndhD-2 and rps14-149 sites. These data suggest that YUC2-mediated auxin biosynthesis governs the RNA-editing process through the ARF1-dependent signal transduction pathway. [ABSTRACT FROM AUTHOR]

The adenovirus C5 E1B-55K protein is crucial for viral replication and is expressed early during infection. It can interact with E4orf6 to form a complex that functions as a ubiquitin E3 ligase. This complex targets specific cellular proteins and marks them for ubiquitination and, predominantly, subsequent proteasomal degradation. E1B-55K interacts with various proteins, with p53 being the most extensively studied, although identifying binding sites has been challenging. To explain the diverse range of proteins associated with E1B-55K, we hypothesized that other binding partners might recognize the simple p53 binding motif (xWxxxPx). In silico analyses showed that many known E1B-55K binding proteins possess this amino acid sequence; therefore, we investigated whether other xWxxxPx-containing proteins also bind to E1B-55K. Our findings revealed that many cellular proteins, including ATR, CHK1, USP9, and USP34, co-immunoprecipitate with E1B-55K. During adenovirus infection, several well-characterized E1B-55K binding proteins and newly identified interactors, including CSB, CHK1, and USP9, are degraded in a cullin-dependent manner. Notably, certain binding proteins, such as ATR and USP34, remain undegraded during infection. Structural predictions indicate no conservation of structure around the proposed binding motif, suggesting that the interaction relies on the correct arrangement of tryptophan and proline residues. [ABSTRACT FROM AUTHOR]

Examines feasibility and effectiveness of implementing a directive education program called "Let Me Decide" to veterans living in Ontario. Discusses two methods used to evaluate implementation of the program. Reports that 97% of the veterans found the education process beneficial whether or not they completed the directives. (Author/JDM)

Background: Alzheimer disease (AD) patients experience progressive neurological and cognitive decline attributed to neurodegeneration. Cerebral dopamine neurotrophic factor (CDNF) has been identified to protect and rescue neurons in various preclinical neurodegeneration models. The expression of this protein occurs in both the central nervous system and peripheral blood. Blood platelets exhibit several biochemical impairments similar to the brain tissues of patients with neurological disorders. This study examines CDNF mRNA expression in human blood platelets in healthy subjects and Alzheimer-probable patients.Methods: Platelets were extracted from whole blood from patients. mRNA was extracted to synthesize cDNA and quantify CDNF gene expression from 21 Alzheimer-probable patients and 73 healthy age-matched control subjects using real-time qPCR. Grouping analysis of the data with regard to sex was conducted.Results: CDNF mRNA expression was significantly decreased in Alzheimer-probable patients relative to the control subjects (P<0.05). Further analysis demonstrated reduced CDNF expression in male Alzheimer-probable patients compared with their age and sex-matched controls (P<0.05). However, no change in female subjects was observed. Interestingly, there is a lower level of CDNF expression in the female control group relative to the control male group (P<0.05).Conclusion: Alzheimer-probable male patients demonstrated significant reductions in CDNF expression, suggesting that CDNF plays a significant role in the pathogenesis of AD. In addition, it may assist in diagnosing male Alzheimer patients. [ABSTRACT FROM AUTHOR]

It has long been established that group-A adenoviruses (HAdV-A12, -A18 and -A31) can cause tumours in new-born rodents with tumourigenicity related to the presence of a unique spacer region located between conserved regions 2 and 3 within the HAdV-A12E1A protein. Group B adenoviruses are weakly oncogenic whereas most of the remaining human adenoviruses are non-oncogenic. In order to understand better the relationship between the structure of the AdE1A spacer region and oncogenicity of HAdVs the structure of synthetic peptides identical or very similar to the adenovirus 12 E1A spacer region were determined to be a-helical using NMR spectroscopy. This contrasts significantly with some previous suggestions that this region is unstructured. Using available predictive algorithms, the structures of spacer regions from other E1As were also examined and the extent of predicted a-helix was found to correlate reasonably well with the tumorigenicity of the respective viruses. We suggest that this may represent an, as yet unknown, binding site for a partner protein required for tumourigenesis. [ABSTRACT FROM AUTHOR]

Background: Cutoff values of cognitive screen tests vary according to age and educational levels.Objective: The objective of this study was to compare the accuracy and determine cutoffs for 3 short cognitive screening instruments: the Mini-Mental State Examination, Montreal Cognitive Assessment (MoCA), and Quick Mild Cognitive Impairment Screen-Turkish version (Qmci-TR), in older adults with low literacy in Turkey.Methods: In all 321 patients, 133 with subjective cognitive complaints (SCC), 88 amnestic-type mild cognitive impairment (aMCI), and 100 with probable Alzheimer disease (AD) with a median of 5 years education were included. Education and age-specific cutoffs were determined.Results: For the overall population, the Qmci-TR was more accurate than the MoCA in distinguishing between aMCI and AD (area under the curve=0.83 vs. 0.76, P=0.004) and the Qmci-TR and Mini-Mental State Examination were superior to the MoCA in discriminating SCC from aMCI and AD. All instruments had similar accuracy among those with low literacy (primary school and lower educational level or illiterate).Conclusions: To distinguish between SCC, aMCI, and AD in a sample of older Turkish adults, the Qmci-TR may be preferable. In very low literacy, the choice of the instrument appears less important. [ABSTRACT FROM AUTHOR]

I B In Reply: b i We thank Isik and colleagues for their response and feedback on our article. In our study, as with others, the GDS-15 was performed only for screening and not for the diagnosis of depression.[1] After screening with the GDS-15, a comprehensive geriatric assessment was conducted. Isik and colleagues refer to our use of the GDS-15 to identify patients with depression and our application of a cut-off score of >=7 for the diagnosis of depression. [Extracted from the article]

Abstract: Adenovirus early region 1A (AdE1A) binds to the C-terminal binding protein 1 (CtBP1) primarily through a highly conserved PXDLS motif located close to its C-terminus. Purified synthetic peptides equivalent to this region of AdE1A have been shown to form a series of β-turns. In this present study the effect of CtBP1 binding on the conformation of C-terminal region of Ad12E1A has been investigated. Using one- and two-dimensional 1H NMR spectroscopy, the conformation of 20-residue peptides equivalent to amino acids I241–V260 and E247–N266 of Ad12E1A were examined in the absence of CtBP1. Whilst the latter peptide forms a series of β-turns in its C-terminal half as reported previously, the former peptide is α-helical over the region D243–Q253. Upon interaction with CtBP1 the conformation of the backbone in the region 255PVDLCVK261 of the Ad12E1A E247–N266 peptide reorganises from a predominately β-turn to an α-helical conformation. This structural isomerisation is characterised by a shift upfield of 0.318 ppm for the δ-CH3 proton resonance of V256. 2-D NOESY experiments showed new signals in the amide-α region which correlate to transferred NOEs from the protein to the peptide residues E251, V256 and K261. In further analyses the contribution of individual amino acids within the sequence 254VPVDLS259 was assessed for their importance in determining structure and consequently affinity of the peptide for CtBP. It has been concluded that Ad12E1A residues 255P–V260 serve initially as a recognition site for CtBP and then as an anchor through a β-turns→α-helix conformational rearrangement. In addition it has been predicted that regions N-terminal to the PXDLS motif in AdE1As from different virus serotypes and from mammalian proteins form α-helices. [Copyright &y& Elsevier]

Presents insights on deaf counselors and counseling service, based on personal experience. Work experience as a deaf counselor in New Zealand; Challenges as a counselor; Limitations on counseling service for the deaf in provincial cities.

An analogue of elongation factor Tu (EF-Tu) from Escherichia coil was prepared by biosynthetic incorporation of 3-fluorotyrosine. The 19F-NMR spectra of the binary complexes of this protein with GDP, GTP and elongation factor Ts (EF-Ts) and the ternary complexes EF-Tu · GDP · aurodox and EF-Tu · GDP · EF-Ts were measured. EF-Tu contains ten tyrosine residues and all of the complexes studied gave complex 19F spectra with overlapping resonances. EF-Tu · GDP gave a spectrum in which two signals were markedly different from those shown by the other complexes, the two resonances being shifted downfield by at least 3.4 ppm and 0.9 ppm relative to their shifts in the other complexes. Such large downfield shifts can be explained by second-order electric field shielding effects resulting from these two tyrosine residues being in a sterically constrained environment in EF-Tu · GDP and with the steric restraints being released in all of the other complexes. The X-ray diffraction structure of EF-Tu · GDP shows that Tyr87 in the N-terminal domain (domain I) and Tyr309 in the C-terminal domain (domain III) are both buried within the protein and are close to each other: these residues are in regions of EF-Tu previously implicated in the structural changes between EF-Tu. GDP and EF-Tu · GTP by other workers. If these tyrosine residues correspond to the two downfield resonances of the spectra of EF-Tu · GDP, the results from the 19F-NMR would be consistent with these earlier indications that domain I interacts closely with domain III in EF-Tu · GDP and that the amino acids between Gly83 and Gly 100 are an important part of this interaction. For all the other complexes studied, these tyrosines are in a less sterically crowded environment consistent with a weaker interaction between the two domains. The 19F-NMR spectrum of the trypsin-cleaved product of EF-Tu · GDP, from which the X-ray diffraction structural data have been obtained, shows no signifcant differences from the native protein so that trypsin cleavage causes no large changes in the proteinߣs structure. [ABSTRACT FROM AUTHOR]

The article discusses the issue of oocyte freezing in human reproduction in Australia. Cryopreservation of unfertilized oocytes for later use is considered a viable technology in inducing pregnancy. Oocyte cryopreservation is utilized as a form of insurance against age-related infertility. Two pregnancies using frozen oocytes for social reasons are described. The disadvantages of oocyte freezing for social infertility reasons are also discussed.

Highlights • MORF2 tightly associates with MORF9 to regulate RNA editing in chloroplast. • MORF2 and MORF9 do not directly bind to plastid editing sites. • MORF2 and MORF9 are present in the same complex of Arabidopsis chloroplast. Abstract RNA editing in chloroplasts and mitochondria is performed by hypothetical editosomes. The MORF family proteins are essential components of these editosomes. In Arabidopsis , MORF2 and MORF9 are involved in the editing of most sites in chloroplasts. In this work, we performed immunoprecipitation and mass spectrometry assays of transgenic lines expressing MORF2-4xMYC and MORF9-4xMYC to identify interacting proteins. We found that MORF2 and MORF9 are present in the same complex. Blue-Native PAGE analysis of chloroplast protein complexes also revealed that both MORF2 and MORF9 are part of a complex of approximately 140 kDa, suggesting the existence of tight MORF2-MORF9 interaction in chloroplasts. The editing of ndhD -1 (ndhD -C2) site was reported to be blocked in both morf2 and morf9. RNA immunoprecipitation assays showed that MORF2 and MORF9 are tightly associated with the editing site of ndhD -1. However, in an RNA-EMSA assay MORF2 and MORF9 could not directly bind to transcripts harboring the editing site of ndhD -1. Taken together, these results indicate that the MORF2-MORF9 heterodimer is the core members of editosomes in chloroplasts, while they are not responsible for RNA editing site recognition. [ABSTRACT FROM AUTHOR]

It has been reported that Arabidopsis chloroplast accD transcripts undergo RNA editing and that loss of accD-C794 RNA editing does not affect plant growth under normal conditions. To date, the exact biological role of accD-C794 editing has remained elusive. Here, we reveal an unexpected role for accD-C794 editing in response to heat stress. Loss of accD-C794 editing results in a yellow and dwarf phenotype with decreased chloroplast gene expression under heat stress, and artificial improvement of C794-edited accD gene expression enhances heat tolerance in Arabidopsis. These data suggest that accD-C794 editing confers heat tolerance in planta. We also found that treatment with the product of acetyl coenzyme A carboxylase (ACCase) could allay mutant phenotypic characteristics and showed that a mutation in the CAC3 gene for the α-subunit of ACCase was associated with dwarfism under heat stress. These observations indicate that defective accD-C794 editing may be intrinsic to reduced ACCase activity, thereby contributing to heat sensitivity. ACCase catalyzes the committed step of de novo fatty acid (FA) biosynthesis. FA content analysis revealed that unsaturated oleic (C18:1) and linoleic acids (C18:2) were low in the accD-C794 editing-defective mutant but high in the C794-edited accD-overexpressing plants compared with the wild type. Supplying exogenous C18:1 and C18:2 could rescue the mutant phenotype, suggesting that these FAs play an essential role in tolerance to heat stress. Transmission electron microscopy observations showed that heat stress seriously affected the membrane architecture in accD editing-defective mutants but not in accD-overexpressing plants. These results provide the first evidence that accD-C794 editing regulates FA biosynthesis for maintenance of membrane structural homeostasis under heat stress., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)