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Graphical abstract, Codon degeneracy of amino acid sequences permits an additional “mRNP code” layer underlying the genetic code that is related to RNA processing. In pre-mRNA splicing, splice site usage is determined by both intrinsic strength and sequence context providing RNA binding sites for splicing regulatory proteins. In this study, we systematically examined modification of splicing regulatory properties in the neighborhood of a GT site, i.e. potential splice site, without altering the encoded amino acids. We quantified the splicing regulatory properties of the neighborhood around a potential splice site by its Splice Site HEXplorer Weight (SSHW) based on the HEXplorer score algorithm. To systematically modify GT site neighborhoods, either minimizing or maximizing their SSHW, we designed the novel stochastic optimization algorithm ModCon that applies a genetic algorithm with stochastic crossover, insertion and random mutation elements supplemented by a heuristic sliding window approach. To assess the achievable range in SSHW in human splice donors without altering the encoded amino acids, we applied ModCon to a set of 1000 randomly selected Ensembl annotated human splice donor sites, achieving substantial and accurate changes in SSHW. Using ModCon optimization, we successfully switched splice donor usage in a splice site competition reporter containing coding sequences from FANCA, FANCB or BRCA2, while retaining their amino acid coding information. The ModCon algorithm and its R package implementation can assist in reporter design by either introducing novel splice sites, silencing accidental, undesired splice sites, and by generally modifying the entire mRNP code while maintaining the genetic code.

Plakophilin 3 (PKP3) is a component of desmosomes and is frequently overexpressed in cancer. Using keratinocytes either lacking or overexpressing PKP3, we identify a signaling axis from ERK to the retinoblastoma (RB) protein and the E2F1 transcription factor that is controlled by PKP3. RB and E2F1 are key components controlling G1/S transition in the cell cycle. We show that PKP3 stimulates the activity of ERK and its target RSK1. This inhibits expression of the transcription factor RUNX3, a positive regulator of the CDK inhibitor CDKN1A/p21, which is also downregulated by PKP3. Elevated CDKN1A prevents RB phosphorylation and E2F1 target gene expression, leading to delayed S phase entry and reduced proliferation in PKP3-depleted cells. Elevated PKP3 expression not only increases ERK activity but also captures phosphorylated RB (phospho-RB) in the cytoplasm to promote E2F1 activity and cell-cycle progression. These data identify a mechanism by which PKP3 promotes proliferation and acts as an oncogene.

This paper highlights artists' role in creating a just city. Drawing on Jane Jacobs' insights on the importance of design for a diverse city and her analysis of the visual order of cities, I argue that artistic interventions are prime examples of the constant negotiation processes that take place in cities. These negotiation processes affect the power relations of the urban society and contribute to constituting urban public spheres. In addition, by shedding light on the processes of producing urban public spaces at locations, for example through artistic interventions, the article emphasises the non-fixity of the city as socio-material entity. The article proposes to understand these negotiation processes and the city's dynamic nature as central to ‘making the just city’ and to allow for equity, democracy and diversity, the key elements of a just city.

Determination of neutralizing antibody titers is still considered the gold standard for infection protection. A full virus neutralization test (VNT) with replication-competent, infectious SARS-CoV-2, is labor-intensive and requires Biosafety Level 3 certified laboratories. Therefore, several commercial SARS-CoV-2 surrogate virus neutralization tests (sVNTs) have been developed that aim to detect neutralizing antibodies targeting the receptor binding domain (RBD) of the viral spike glycoprotein (S). Neutralizing antibodies to the RBD block its interaction with the angiotensin-converting enzyme 2 (ACE2) receptor protein. Here, we compared a full virus neutralization test (VNT) with two SARS-CoV-2 surrogate virus neutralization tests (sVNT) and validated them in two cohorts of i) convalescent SARS-CoV-2-infected individuals and ii) COVID vaccinated individuals. The sVNTs showed highly different results both, compared to the VNT-titers and also between the two cohorts. This indicates that currently, sVNT provide a qualitative instead of a quantitative measurement of neutralizing antibodies. The findings in this work show that the cutoff levels for sVNTs might need to be readjusted for convalescent and vaccinated individuals.

Primary/secondary hyperoxalurias involve nephrocalcinosis-related chronic kidney disease (CKD) leading to end-stage kidney disease. Mechanistically, intrarenal calcium oxalate crystal deposition is thought to elicit inflammation, tubular injury and atrophy, involving the NLRP3 inflammasome. Here, we found that mice deficient in NLRP3 and ASC adaptor protein failed to develop nephrocalcinosis, compromising conclusions on nephrocalcinosis-related CKD. In contrast, hyperoxaluric wild-type mice developed profound nephrocalcinosis. NLRP3 inhibition using the β-hydroxybutyrate precursor 1,3-butanediol protected such mice from nephrocalcinosis-related CKD. Interestingly, the IL-1 inhibitor anakinra had no such effect, suggesting IL-1-independent functions of NLRP3. NLRP3 inhibition using 1,3-butanediol treatment induced a shift of infiltrating renal macrophages from pro-inflammatory (CD45+F4/80+CD11b+CX3CR1+CD206-) and pro-fibrotic (CD45+F4/80+CD11b+CX3CR1+CD206+TGFβ+) to an anti-inflammatory (CD45+F4/80+CD11b+CD206+TGFβ-) phenotype, and prevented renal fibrosis. Finally, in vitro studies with primary murine fibroblasts confirmed the non-redundant role of NLRP3 in the TGF-β signaling pathway for fibroblast activation and proliferation independent of the NLRP3 inflammasome complex formation. Thus, nephrocalcinosis-related CKD involves NLRP3 but not necessarily via intrarenal IL-1 release but rather via other biological functions including TGFR signaling and macrophage polarization. Hence, NLRP3 may be a promising therapeutic target in hyperoxaluria and nephrocalcinosis.

The reaction of bis(3,5-dimethylpyrazol-1-yl)acetic acid (Hbdmpza) with metal(II) acetates [M(OAc)2] (M = Mn, Co and Fe) yields a series of homoleptic first row transition metal complexes: [Mn(bdmpza)2] (1), [Co(bdmpza)2] (2) and [Fe(bdmpza)2] (3). Subsequent oxidation results in the formation of the trivalent complexes [Mn(bdmpza)2]BF4 (4), [Co(bdmpza)2]BF4 (5) and [Fe(bdmpza)2]BF4 (6). An unidentate binding of the carboxylate donor and thus κ3 coordination of the ligand was determined by IR spectroscopy and single-crystal X-ray diffraction experiments, which also confirm the formation of the homoleptic complexes and the preservation of the geometry during oxidation. Furthermore, the magnetic measurements exhibit that all complexes are in high-spin state with exception of the low-spin complex [Co(bdmpza)2]BF4 (5). The high-spin complex [Mn(bdmpza)2]BF4 (4) displays a Jahn–Teller distortion. In addition, the divalent and trivalent complexes show promising spectroscopic and electrochemical properties regarding their suitability as potential redox mediators for dye-sensitized solar cells (DSSCs).

Reactions of carbon-rich bispropargyl alcohols with two equivalents of the ruthenium precursor [RuCl(η5-C5H5)(PPh3)2] and NH4[PF6], respectively, result in dinuclear ruthenium bisallenylidene complexes [Ru(η5-C5H5)(PPh3)2( C C )(AC)( C C )(PPh3)2(η5-C5H5)Ru](PF6)2 (7), [Ru(η5-C5H5)(PPh3)2( C C )(PC)( C C )(PPh3)2(η5-C5H5)Ru](PF6)2 (9), [Ru(η5-C5H5)(PPh3)2( C C )(BAN)( C C )(PPh3)2(η5-C5H5)Ru](PF6)2 (10), and [Ru(η5-C5H5)(PPh3)2( C C )(IndFN)( C C )(PPh3)2(η5-C5H5)Ru](PF6)2 (11) (polyaromatic moieties: AC = anthracene, PC = pentacene, BAN = bianthracene, IndFN = indenofluorene). These complexes show distinct spectroscopic and electronic properties, which could be investigated by cyclic voltammetry and UV/Vis/NIR spectroscopic measurements.

PMMA gels synthesized by RAFT polymerization and corresponding gels made by free radical polymerization (FRP) were characterized macroscopically by determining the shear moduli and the swelling ratios, and microscopically by dynamic light scattering (DLS) with particular emphasis on inhomogeneity. The gels were prepared in the solvent γ-butyrolactone at concentrations ranging from 13 to 20 wt% (15–22.5 vol%). The cross-linking efficiency attained in RAFT polymerizations was significantly smaller than that obtained in corresponding FRPs. This means that in RAFT polymerizations more cross-links were wasted in network imperfections. The static fraction of the total ensemble-averaged scattering intensity determined by DLS was used as a measure of inhomogeneity. This quantity decreased with rising amount of RAFT agent and when going from FRP to RAFT polymerization. However, since the effective network density decreased concurrently, the influence of the polymerization mechanism on homogeneity is just an apparent one. The RAFT gels are not more homogeneous than the FRP gels when the comparison is based on systems having the same effective network density. On the contrary, RAFT gels prepared with a high content of RAFT agent appear slightly less homogeneous than those made with a lower content of RAFT agent or via FRP, provided gels having identical moduli are compared.

Elaborate research on splicing, starting in the late seventies, evolved from the discovery that 5' splice sites are recognized by their complementarity to U1 snRNA towards the realization that RNA duplex formation cannot be the sole basis for 5'ss selection. Rather, their recognition is highly influenced by a number of context factors including transcript architecture as well as splicing regulatory elements (SREs) in the splice site neighborhood. In particular, proximal binding of splicing regulatory proteins highly influences splicing outcome. The importance of SRE integrity especially becomes evident in the light of human pathogenic mutations where single nucleotide changes in SREs can severely affect the resulting transcripts. Bioinformatics tools nowadays greatly assist in the computational evaluation of 5'ss, their neighborhood and the impact of pathogenic mutations. Although predictions are already quite robust, computational evaluation of the splicing regulatory landscape still faces challenges to increase future reliability. This article is part of a Special Issue entitled: RNA structure and splicing regulation edited by Francisco Baralle, Ravindra Singh and Stefan Stamm.

Alpine winter sports are very popular in Austria, and Austrians have had much international success in alpine ski racing, snowboarding and ski cross. These sports demand high physical fitness levels in all age groups. Sport-specific tests are crucial to effectively monitor training programs and individual fitness. The following article provides an overview of physical testing with a special emphasis on sport-specific tests used in young and elite athletes, such as bench press and pull tests, loaded power test, snowboard and ski cross start test and gliding test.

Introduction Healthy and pathological ageing, such as Alzheimer’s disease (AD), both co-occur with disruptions of neuronal activity in memory networks. A prodromal phase of AD is mild cognitive impairment (MCI). Transcranial current stimulation (tCS) has previously been implemented in various settings, showing to have beneficial influences on network connectivity. The recollection and hippocampal networks are vulnerable to AD-related pathology. Targeting these networks with tCS in an early phase may be a valid disease-delaying approach. The hippocampus cannot be stimulated directly, but is closely connected with the angular gyrus. By stimulating the angular gyrus during memory performance makes the recollection network more susceptible and therefore, we hypothesize that indirect effects might be detected in the hippocampus. Further, we will investigate the neural and cognitive effects of single vs multiple sessions. Knowledge about the (long-term) cognitive and neural mechanisms can give valuable insights and pave the ground for exploring tCS as a treatment option in future studies. Objectives We aim to investigate the neural changes underlying tACS on the angular gyrus in MCI patients and in healthy controls using simultaneous fMRI, and the effect of repeated vs. first-session tACS. Performance on a memory task will be compared between sessions. A hippocampus-driven pattern separation memory task will be implemented to investigate if tACS vs. sham during the encoding and consolidation phase has an influence on brain activation during subsequent retrieval. Transfer to a similar, non-practiced task will be assessed at follow-up. Patients & methods or materials & methods 20 MCI patients and 20 healthy controls will receive 1 sham-tACS session, 5 consecutive tACS-sessions, and one follow-up session. FMRI-scans will be obtained during sham, on the first and fifth active session and one week after the last active session. TACS will be applied online during encoding (task-fMRI) and consolidation (resting-state-fMRI) of a pattern separation task. Parallel task-versions will be used in randomized order to minimize learning effects. Within- and between group analyses will be conducted on both the fMRI-data (task and rs-fMRI) and the behavioural data (pattern separation performance). Download : Download high-res image (311KB) Download : Download full-size image