SUMO protease FUG1, histone reader AL3 and chromodomain protein LHP1 are integral to repeat expansion-induced gene silencing in Arabidopsis thaliana.

Epigenetic gene silencing induced by expanded repeats can cause diverse phenotypes ranging from severe growth defects in plants to genetic diseases such as Friedreich's ataxia in humans. The molecular mechanisms underlying repeat expansion-induced epigenetic silencing remain largely unknown. Using a plant model with a temperature-sensitive phenotype, we have previously shown that expanded repeats can induce small RNAs, which in turn can lead to epigenetic silencing through the RNA-dependent DNA methylation pathway. Here, using a genetic suppressor screen and yeast two-hybrid assays, we identified novel components required for epigenetic silencing caused by expanded repeats. We show that FOURTH ULP GENE CLASS 1 (FUG1)-an uncharacterized SUMO protease with no known role in gene silencing-is required for epigenetic silencing caused by expanded repeats. In addition, we demonstrate that FUG1 physically interacts with ALFIN-LIKE 3 (AL3)-a histone reader that is known to bind to active histone mark H3K4me2/3. Loss of function of AL3 abolishes epigenetic silencing caused by expanded repeats. AL3 physically interacts with the chromodomain protein LIKE HETEROCHROMATIN 1 (LHP1)-known to be associated with the spread of the repressive histone mark H3K27me3 to cause repeat expansion-induced epigenetic silencing. Loss of any of these components suppresses repeat expansion-associated phenotypes coupled with an increase in IIL1 expression with the reversal of gene silencing and associated change in epigenetic marks. Our findings suggest that the FUG1-AL3-LHP1 module is essential to confer repeat expansion-associated epigenetic silencing and highlight the importance of post-translational modifiers and histone readers in epigenetic silencing.

Efficacy of a high-intensity home stretching device and traditional physical therapy in non-operative management of adhesive capsulitis - a prospective, randomized control trial.

BACKGROUND: Historically, in-person physical therapy serves as a foundational component of nonoperative treatment of adhesive capsulitis (AC). This study compares the effectiveness of an at-home high-intensity stretch (HIS) device to traditional physical therapy (PT) and to PT in combination with the HIS device. We hypothesize that the HIS device will be as effective as PT alone or as combination therapy in the first-line treatment of AC and use of the HIS device will exhibit improvement at higher rate. METHODS: Thirty-four patients with idiopathic adhesive capsulitis and a minimum of 12 months follow-up were included in this study. Patients were randomized into one of the three groups: HIS device, PT alone, or HIS device + PT. Passive range of motion (ROM), American Shoulder and Elbow Surgeons (ASES), and Simple Shoulder Test (SST) scores were measured. Additionally, patient satisfaction, compliance and complications were recorded. Paired t-test, ANOVA and Chi-squared tests were used in analysis. RESULTS: Final ROM in all planes improved for all groups compared to baseline (p < 0.001), with only HIS device group able to restore > 95% of contralateral ROM in all planes at final follow-up. Patients with PT alone were on average slowest to improve ROM from baseline, at 3 months, 6 months, and 1 year in all planes except internal rotation. ASES and SST scores improved for all groups when compared to baseline (p < 0.001). Use of HIS-device resulted in greater improvement in SST and ASES Total scores compared to PT alone (p = 0.045, and p = 0.048, respectively). CONCLUSIONS: Use of an at-home high-intensity stretching device for conservative treatment of idiopathic adhesive capsulitis improves outcomes in ROM and in ASES and SST scores both when used as an adjunct to physical therapy and when used alone. TRIAL REGISTRATION: The study protocol was registered at www. CLINICALTRIALS: gov (20/05/2022, NCT05384093).

Musculoskeletal Injury in American Football: A Bibliometric Analysis of the Most Cited Articles.

Background: Textbook knowledge and clinical dogma are often insufficient for effective evidence-based decision making when treating musculoskeletal injuries in American football players, given the variability in presentation and outcomes across different sports and different levels of competition. Key evidence can be drawn directly from high-quality published articles to make the appropriate decisions and recommendations for each athlete's unique situation. Purpose: To identify and analyze the 50 most cited articles related to football-related musculoskeletal injury to provide an efficient tool in the arsenal of trainees, researchers, and evidence-based practitioners alike. Study Design: Cross-sectional study. Methods: The ISI Web of Science and SCOPUS databases were queried for articles pertaining to musculoskeletal injury in American football. For each of the top 50 most cited articles, bibliometric elements were evaluated: citation count and density, decade of publication, journal, country, multiple publications by the same first author or senior author, article content (topic, injury area), and level of evidence (LOE). Results: The mean ± SD number of citations was 102.76 ± 37.11; the most cited article, with 227 citations, was "Syndesmotic Ankle Sprains" published in 1991 by Boytim et al. Several authors served as a first or senior author on >1 publication, including J.S. Torg (n = 6), J.P. Bradley (n = 4), and J.W. Powell (n = 4). The American Journal of Sports Medicine published the majority of the 50 most cited articles (n = 31). A total of 29 articles discussed lower extremity injuries, while only 4 discussed upper extremity injuries. The majority of the articles (n = 28) had an LOE of 4, with only 1 article having an LOE of 1. The articles with an LOE of 3 had the highest mean citation number (133.67 ± 55.23; F = 4.02; P = .05). Conclusion: The results of this study highlight the need for more prospective research surrounding the management of football-related injury. The low overall number of articles on upper extremity injury (n = 4) also highlights an area for further research.

CRY2 interacts with CIS1 to regulate thermosensory flowering via FLM alternative splicing.

Cryptochromes (CRYs) are evolutionarily conserved photolyase-like photoreceptors found in almost all species, including mammals. CRYs regulate transcription by modulating the activity of several transcription factors, but whether and how they affect pre-mRNA processing are unknown. Photoperiod and temperature are closely associated seasonal cues that influence reproductive timing in plants. CRYs mediate photoperiod-responsive floral initiation, but it is largely unknown whether and how they are also involved in thermosensory flowering. We establish here that blue light and CRY2 play critical roles in thermosensory flowering in Arabidopsis thaliana by regulating RNA alternative splicing (AS) to affect protein expression and development. CRY2 INTERACTING SPLICING FACTOR 1 (CIS1) interacts with CRY2 in a blue light-dependent manner and promotes CRY2-mediated thermosensory flowering. Blue light, CRYs, and CISs affect transcriptome-wide AS profiles, including those of FLOWERING LOCUS M (FLM), which is critical for temperature modulation of flowering. Moreover, CIS1 binds to the FLM pre-mRNA to regulate its AS, while CRY2 regulates the RNA-binding activity of CIS1. Thus, blue light regulates thermosensory flowering via a CRY2-CIS1-FLM signaling pathway that links flowering responses to both light and ambient temperature.

Epidemiology and Outcomes of Ankle Injuries in the National Football League.

Background: Traumatic ankle injuries are commonly complicated by persistent symptoms and the development of chronic ankle instability. Purpose: To describe the epidemiology of ankle injuries in the National Football League (NFL) and investigate the effects that ankle injuries have on performance metrics in the years after injury. Study Design: Descriptive epidemiologic study. Methods: Ankle injuries sustained by NFL players during the 2015-2016, 2016-2017, and 2017-2018 seasons were identified using the Pro Football Reference database. Cumulative incidence was calculated, and demographic identifiers were collected for each injury. The return-to-play (RTP) rate was also recorded. For each player who met inclusion for the performance analysis, power rating (PR) was calculated for the preinjury season (Y-1) and 2 postinjury seasons (Y+1 and Y+2) as follows: PR = (offensive yards/10) + (total touchdowns × 6) + (combined tackles) + (sacks × 2) + (interceptions × 2). Mean PRs were calculated for each season as well as the percentage change and mean difference in PR between Y-1 and Y+1 (ΔPR1%, ΔPR1) and between Y-1 and Y+2 (ΔPR2%, ΔPR2). Subgroup analyses of PR were performed by player position, injury type, and years of experience. Results: Overall, 668 ankle injuries were identified, with an average cumulative incidence across the 3 seasons of 11.2% and RTP rate of 91%. Of those injuries, 159 met inclusion criteria for the PR analysis. The mean overall PR (96.95 in Y-1) declined 22% in Y+1 to 76.10 (-20.85 [95% CI, -13.82 to -27.89]; P < .001) and 27% in Y+2 to 70.93 (-26.02 [95% CI, -18.04 to -34.00]; P < .001). The mean PR per game played (6.70 in Y-1) decreased 14% in Y+1 to 5.75 (-0.95 [95% CI, -0.56 to -1.34]; P < .001) and 17% in Y+2 to 5.54 (-1.16 [95% CI, -0.63 to -1.62]; P < .001). Conclusion: It was found that ankle injuries hampered the performance of NFL players, even multiple years after the injury occurred, despite a relatively high RTP rate. There was a decrease in total games played after ankle injuries as well as a decreased performance output per game played.

Natural variation at the Drosophila melanogaster Or22 odorant receptor locus is associated with changes in olfactory behaviour.

In insects, many critical olfactory behaviours are mediated by the large odorant receptor (Or) gene family, which determines the response properties of different classes of olfactory receptor neurons (ORNs). While ORN responses are generally conserved within and between Drosophila species, variant alleles of the D. melanogaster Or22 locus have previously been shown to alter the response profile of an ORN class called ab3A. These alleles show potential clinal variation, suggesting that selection is acting at this locus. Here, we investigated if the changes seen in ab3A responses lead to changes in olfactory-related behaviours. We show that variation at the Or22 locus and in the ab3A neurons are not fully compensated for by other ORNs and lead to overall changes in antennal odorant detection. We further show that this correlates with differences in odorant preference behaviour and with differences in oviposition site preference, with flies that have the chimaeric short allele strongly preferring to oviposit on banana. These findings indicate that variation at the Or22 locus leads to changes in olfactory-driven behaviours, and add support to the idea that the ab3A neurons are of especial importance to the ecology of Drosophila flies.

Quantifying splice-site usage: a simple yet powerful approach to analyze splicing.

RNA splicing, and variations in this process referred to as alternative splicing, are critical aspects of gene regulation in eukaryotes. From environmental responses in plants to being a primary link between genetic variation and disease in humans, splicing differences confer extensive phenotypic changes across diverse organisms (1-3). Regulation of splicing occurs through differential selection of splice sites in a splicing reaction, which results in variation in the abundance of isoforms and/or splicing events. However, genomic determinants that influence splice-site selection remain largely unknown. While traditional approaches for analyzing splicing rely on quantifying variant transcripts (i.e. isoforms) or splicing events (i.e. intron retention, exon skipping etc.) (4), recent approaches focus on analyzing complex/mutually exclusive splicing patterns (5-8). However, none of these approaches explicitly measure individual splice-site usage, which can provide valuable information about splice-site choice and its regulation. Here, we present a simple approach to quantify the empirical usage of individual splice sites reflecting their strength, which determines their selection in a splicing reaction. Splice-site strength/usage, as a quantitative phenotype, allows us to directly link genetic variation with usage of individual splice-sites. We demonstrate the power of this approach in defining the genomic determinants of splice-site choice through GWAS. Our pilot analysis with more than a thousand splice sites hints that sequence divergence in cis rather than trans is associated with variations in splicing among accessions of Arabidopsis thaliana. This approach allows deciphering principles of splicing and has broad implications from agriculture to medicine.

The integral spliceosomal component CWC15 is required for development in Arabidopsis.

Efficient mRNA splicing is a prerequisite for protein biosynthesis and the eukaryotic splicing machinery is evolutionarily conserved among species of various phyla. At its catalytic core resides the activated splicing complex Bact consisting of the three small nuclear ribonucleoprotein complexes (snRNPs) U2, U5 and U6 and the so-called NineTeen complex (NTC) which is important for spliceosomal activation. CWC15 is an integral part of the NTC in humans and it is associated with the NTC in other species. Here we show the ubiquitous expression and developmental importance of the Arabidopsis ortholog of yeast CWC15. CWC15 associates with core components of the Arabidopsis NTC and its loss leads to inefficient splicing. Consistent with the central role of CWC15 in RNA splicing, cwc15 mutants are embryo lethal and additionally display strong defects in the female haploid phase. Interestingly, the haploid male gametophyte or pollen in Arabidopsis, on the other hand, can cope without functional CWC15, suggesting that developing pollen might be more tolerant to CWC15-mediated defects in splicing than either embryo or female gametophyte.

Effects of linear periodization versus daily undulating periodization on neuromuscular performance and activities of daily living in an elderly population.

BACKGROUND: Periodization is a systematic training calendar designed to provide variations in performance targeting, while maximizing results and reducing the potential for overtraining. When provided across multiple weeks, termed a mesocycle, it may also incorporate active recovery periods using specified drills designed to translate neuromuscular gains into targeted functional abilities. There are a number of models that can be used when applying periodization to resistance training (RT). Among the most common are the linear (LP) and daily fixed non-linear (NLP) models. It is currently unknown whether an optimal periodization strategy exists that will maximize benefits for older adults; therefore, we compared the impact of these two periodization models on neuromuscular and functional measures in a group of older persons living independently in the community. METHODS: Thirty-six older adults, 58-80 years of age, were randomly assigned to either a LP (n = 16; 69.3 ±â€¯4.6 y) or NLP (n = 14; 68.9 ±â€¯6.7 y) group. The LP group performed 12 weeks of training comprised of separate 4-week strength and power training cycles, each followed by a 2-week recovery period incorporating translational exercises. The NLP group performed the strength, power, and translational training on three separate days during the week. Neuromuscular testing included seated chest press and leg press strength and power tests, while physical function testing included the gallon jug shelf test, laundry transfer test, floor stand-up, chair-to-stand test, and 8 foot timed up-and-go. RESULTS: 3 (time) × 2 (sex) × 2 (group) repeated measures ANOVA revealed both periodization strategies were equally effective at inducing neuromuscular and functional improvements and that men generally produced more strength and power than women. CONCLUSIONS: Both LP and NLP can be used to improve strength, power, and functional performance in healthy untrained older adults when strength, power and functional training cycles are involved. Therefore, personal preference and variety should be considered when deciding which approach to use, provided high-speed power and translational recovery components are included.

SRSF3 promotes pluripotency through Nanog mRNA export and coordination of the pluripotency gene expression program.

The establishment and maintenance of pluripotency depend on precise coordination of gene expression. We establish serine-arginine-rich splicing factor 3 (SRSF3) as an essential regulator of RNAs encoding key components of the mouse pluripotency circuitry, SRSF3 ablation resulting in the loss of pluripotency and its overexpression enhancing reprogramming. Strikingly, SRSF3 binds to the core pluripotency transcription factor Nanog mRNA to facilitate its nucleo-cytoplasmic export independent of splicing. In the absence of SRSF3 binding, Nanog mRNA is sequestered in the nucleus and protein levels are severely downregulated. Moreover, SRSF3 controls the alternative splicing of the export factor Nxf1 and RNA regulators with established roles in pluripotency, and the steady-state levels of mRNAs encoding chromatin modifiers. Our investigation links molecular events to cellular functions by demonstrating how SRSF3 regulates the pluripotency genes and uncovers SRSF3-RNA interactions as a critical means to coordinate gene expression during reprogramming, stem cell self-renewal and early development.

A Polynucleotide Repeat Expansion Causing Temperature-Sensitivity Persists in Wild Irish Accessions of Arabidopsis thaliana.

Triplet repeat expansions underlie several human genetic diseases such as Huntington's disease and Friedreich's ataxia. Although such mutations are primarily known from humans, a triplet expansion associated genetic defect has also been reported at the IIL1 locus in the Bur-0 accession of the model plant Arabidopsis thaliana. The IIL1 triplet expansion is an example of cryptic genetic variation as its phenotypic effects are seen only under genetic or environmental perturbation, with high temperatures resulting in a growth defect. Here we demonstrate that the IIL1 triplet expansion associated growth defect is not a general stress response and is specific to particular environmental perturbations. We also confirm and map genetic modifiers that suppress the effect of IIL1 triplet repeat expansion. By collecting and analyzing accessions from the island of Ireland, we recover the repeat expansion in wild populations suggesting that the repeat expansion has persisted at least 60 years in Ireland. Through genome-wide genotyping, we show that the repeat expansion is present in diverse Irish populations. Our findings indicate that even deleterious alleles can persist in populations if their effect is conditional. Our study demonstrates that analysis of groups of wild populations is a powerful tool for understanding the dynamics of cryptic genetic variation.

Nonsense-mediated mRNA decay modulates FLM-dependent thermosensory flowering response in Arabidopsis.

Increasing global temperatures have an impact on flowering, and the underlying mechanisms are just beginning to be unravelled(1,2). Elevated temperatures can induce flowering, and different mechanisms that involve either activation or de-repression of FLOWERING LOCUS T (FT) by transcription factor PHYTOCHROME INTERACTING FACTOR 4 (PIF4) or the FLOWERING LOCUS M (FLM)-SHORT VEGETATIVE PHASE (SVP) complex, respectively, have been suggested to be involved(3-6). Thermosensitivity in flowering has been mapped to FLM(5), which encodes a floral repressor(7,8). FLM undergoes alternative splicing(8) and it has been suggested that temperature-dependent alternative splicing leads to differential accumulation of the FLM-ß and FLM-δ transcripts, encoding proteins with antagonistic effects, and that their ratio determines floral transition(4). Here we show that high temperatures downregulate FLM expression by alternative splicing coupled with nonsense-mediated mRNA decay (AS-NMD). We identify thermosensitive splice sites in FLM and show that the primary effect of temperature is explained by an increase in NMD target transcripts. We also show that flm is epistatic to pif4, which suggests that most of the PIF4 effects are FLM dependent. Our findings suggest a model in which the loss of the floral repressor FLM occurs through mRNA degradation in response to elevated temperatures, signifying a role for AS-NMD in conferring environmental responses in plants.