Selective recruitment of stress-responsive mRNAs to ribosomes for translation by acetylated protein S1 during nutrient stress in Escherichia coli.

The chemical modification of ribosomes plays an important regulatory role in cellular translation adaptation in response to environmental stresses. Nevertheless, how the modified ribosome reprograms the translation machinery for the preferential expression of the specific mRNAs encoding stress-responsive proteins to stress remains poorly understood. Here, we find that AcP-induced acetylation of K411 and K464 in ribosomal protein S1 during carbon-nitrogen imbalance, which in turn impacts its binding with distinct mRNAs. S1 acetylation shows differential selectivity for recruiting subsets of mRNAs to ribosomes. Using the RNC-Seq method, we find that mimic acetylated S1 prefers transcripts related with the formation of flagella/biofilms, two-component systems, nitrogen assimilation, amino acid degradation, and lipopolysaccharide biosynthesis, whereas inhibits the translation of mRNAs involved in amino acid biosynthesis and most ribosomal proteins. Importantly, further characterization of S1-binding site (SBS) sequences of mRNAs with different translation efficiencies indicated that the presence of a conserved motif allows coordinated regulation of S1 acetylation-driven translation reprogramming for cell survival during nitrogen starvation. These findings expand the repertoire of ribosome heterogeneity to the acetylation level of S1 at specific sites and its role in the ribosome-mediated regulation of gene expression as a cellular response at the translational level to stress.

Clinical Outcomes of Hip Arthroscopy for Hip Labrum Calcification in Young and Middle-Aged Patients.

OBJECTIVE: To investigate the methods and outcomes of hip arthroscopy for hip labrum calcification, and to discuss the clinical, imaging, and intraoperative findings of hip labrum calcification. METHODS: This is a therapeutic case series study. From January 2015 to June 2018, 15 patients who met the inclusion and exclusion criteria were followed up for at least 2 years for an analysis on the outcomes of arthroscopy in the treatment of hip labrum calcification and the clinical, imaging, and intraoperative findings of the patients. There were eight males and seven females, with an average age of 38.9 ± 8.8 years (range, 23-50 years). The visual analog scale (VAS), the modified Harris hip score (mHSS), and the international hip outcome tool (iHOT-12) were used to evaluate the outcomes of surgery. RESULTS: A total of 15 patients were followed up for at least 2 years (28.1 ± 2.9 months). The average calcified volume was 118.0 mm3 (range, 19.4-609.2 mm3 ) and calcified volume was related to the preoperative hip function score. Thirteen patients had pain in the groin area (86.7%). Labrum calcifications were located (according to the clock distribution) as follows: 14 patients were anterior and superior (11:00-3:00); 12 cases of femoroacetabular impingement (FAI) were observed during operation, including five cases of pincer type, two cases of cam type, and five cases of mixed type. VAS pain score means were 7.73 ± 1.28 before surgery, decreasing to 2.0 ± 0.89 and 1.73 ± 0.79 at 1 and 2 years post-surgery, respectively. mHSS scores were 57.40 ± 6.23 before surgery and 82.10 ± 4.76 and 83.18 ± 4.07, 1 and 2 years post-surgery, respectively; iHOT-12 mean score pre-surgery was 37.67 ± 4.85, increasing to 67.64 ± 5.30 and 72.18 ± 4.49, 1 and 2 years post-surgery, respectively. Compared with preoperative values, postoperative VAS, mHSS, and iHOT-12 scores were significantly improved (P < 0.01); iHOT-12 scores also significantly decreased from 1 to 2 years postoperatively (P = 0.034). No patient had complications. CONCLUSION: Hip arthroscopy is an effective method for the treatment of hip labrum calcification. The size of calcification influenced preoperative symptoms and function. Long-term irritation from FAI may be one important cause of labrum calcification.

[Arthroscopic repair of Bankart lesion with bioabsorbable suture anchors].

OBJECTIVE: To evaluate early clinical effects of bioabsorbable suture anchors for the treatment of Bankart lesion. METHODS: Total 23 patients with the Bankart lesion were treated with arthroscopic repair using bioabsorbable suture anchors from January 2010 to June 2017. There were 20 males and 3 females, with an average age of (23.4±3.9) years old (ranged, 19 to 34 years old). Fourteen patients had injuries on the right shoulder joint and 9 patients had the injuries on the left side. The mechanism of primary dislocation included 17 cases of training, 5 cases of sports injury and 1 case of falling down. The mean interval time from injury to surgery was(10.9±5.8) months (ranged, 3 to 36 months). The Bankart lesion was repaired by bio-cortical suture anchors. The Rowes rating system for Bankart repair was used to evaluate therapeutic effects. RESULTS: All 23 patients were followed up, with a mean duration of(24.5±3.7) months(ranged, 18 to 39 months). At the latest follow up, there was no recurrent dislocation occurred, and all patients had returned to sports and work. The Rowes rating system for Bankart repair was 53.91±11.67 pre-operationally and 91.74±12.30 post operationally, respectively (P<0.01). According to the Rowes rating system, there were 0 case of excellent, 0 case of fine, 9 cases of good and 14 cases of bad pre-operationally;16 cases of excellent, 4 case of fine, 3 cases of good and 0 cases of bad post operationally;the difference was statistically significant (P<0.01). CONCLUSION: Applying bio-cortical bone suture anchors for the Bankart lesion is a reliable, efficient and cost effective treatment, which is also suitable for the revision of the Bankart lesion.

Acetylation of translation machinery affected protein translation in E. coli.

Reversible lysine acetylation (RLA) of translation machinery components, such as ribosomal proteins (RPs) and translation factors (TFs), was identified in many microorganisms, while knowledge of its function and effect on translation remains limited. Herein, we show that translation machinery is regulated by acetylation. Using the cell-free translation system of E. coli, we found that AcP-driven acetylation significantly reduced the relative translation rate, and deacetylation partially restored the translation activity. Hyperacetylation caused by intracellular AcP accumulation or carbon/nitrogen fluctuation (carbon overflow or nitrogen limitation) modulated protein translation in vivo. These results uncovered a critical role of acetylation in translation regulation and indicated that carbon/nitrogen imbalance induced acetylation of ribosome in E. coli and dynamically affected translation rate via a global, uniform manner. KEY POINTS: • Acetylation of translation machinery directly regulated global translation. • K618 of EF-G, K411, and K464 of S1 are the key points influencing translation rate. • Carbon/nitrogen imbalance triggers AcP-dependent acetylation.

Developing a cadmium resistant rice genotype with OsHIPP29 locus for limiting cadmium accumulation in the paddy crop.

Widespread contamination of agricultural soil with toxic metals such as cadmium (Cd) is a major threat to crop production and human health. Metallochaperones are a unique class of proteins that play pivotal roles in detoxifying metallic ions inside cells. In this study, we investigated the biological function of an uncharacterized metallochaperone termed OsHIPP29 in rice plants and showed that OsHIPP29 resides in the plasma membrane and nucleus and detoxifies excess Cd and Zn. OsHIPP29 was primarily expressed in shoots during the vegetative stage and in leaf sheath and spikelet at the flowering stage. It can be differentially induced by excess Cd, Zn, Cu, Fe and Mn. To identify the function of OsHIPP29 in mediating rice response to Cd stress, we examined a pair of OsHIPP29 mutants, RNAi lines and transgenic rice overexpressing OsHIPP29 (OX) under Cd stress. Both mutant and RNAi lines are sensitive to Cd in growth as reflected in decreased plant height and dry biomass. In contrast, the OX lines showed better growth under Cd exposure. Consistent with the phenotype, the OX lines accumulated less Cd in both root and shoot tissues, whereas OsHIPP29 knockout led to higher accumulation of Cd. These results point out that expression of OsHIPP29 is able to contribute to Cd detoxification by reducing Cd accumulation in rice plants. Our work highlights the significance of OsHIPP29-mediated reduced Cd in rice plants, with important implications for further developing genotypes that will minimize Cd accumulation in rice and environmental risks to human health.

OsZIP1 functions as a metal efflux transporter limiting excess zinc, copper and cadmium accumulation in rice.

BACKGROUND: Metal homeostasis is critical for plant growth, development and adaptation to environmental stresses and largely governed by a variety of metal transporters. The plant ZIP (Zn-regulated transporter, Iron-regulated transporter-like Protein) family proteins belong to the integral membrane transporters responsible for uptake and allocation of essential and non-essential metals. However, whether the ZIP family members mediate metal efflux and its regulatory mechanism remains unknown. RESULTS: In this report, we provided evidence that OsZIP1 is a metal-detoxified transporter through preventing excess Zn, Cu and Cd accumulation in rice. OsZIP1 is abundantly expressed in roots throughout the life span and sufficiently induced by excess Zn, Cu and Cd but not by Mn and Fe at transcriptional and translational levels. Expression of OsZIP-GFP fusion in rice protoplasts and tobacco leaves shows that OsZIP1 resides in the endoplasmic reticulum (ER) and plasma membrane (PM). The yeast (Saccharomyces cerevisiae) complementation test shows that expression of OsZIP1 reduced Zn accumulation. Transgenic rice overexpressing OsZIP1 grew better under excess metal stress but accumulated less of the metals in plants. In contrast, both oszip1 mutant and RNA interference (RNAi) lines accumulated more metal in roots and contributed to metal sensitive phenotypes. These results suggest OsZIP1 is able to function as a metal exporter in rice when Zn, Cu and Cd are excess in environment. We further identified the DNA methylation of histone H3K9me2 of OsZIP1 and found that OsZIP1 locus, whose transcribed regions imbed a 242 bp sequence, is demethylated, suggesting that epigenetic modification is likely associated with OsZIP1 function under Cd stress. CONCLUSION: OsZIP1 is a transporter that is required for detoxification of excess Zn, Cu and Cd in rice.

[Progress on relationship between transforming growth factor-beta1 and tendinopathy].

As a common soft tissue disease, the mechanism of tendinopathy has not been clarified and is lack of effective treatment method. Change of tissue fibrosis is the one of the main pathological features. Transforming growth factor beta 1 (TGF-ß1), which is one of the important factor, participated in fibrosis. Inconsonant expressions of TGF-ß1 could be found in tendinopathy. The studies are still controversial, but the vast majority of studies had showed that TGF-ß1 was abnormal, and it is given priority to increase, which means that TGF-ß1 plays an important role in the process of tendinopathy. In the process of tendon injuries and repairs, the time of TGF-ß1 increasing is inconsistent. The time for TGF-ß1 plays a significant role has not been determined. TGF-ß1 has abnormal expressions in both tendinopathy and tendon repairs, which are two opposite processes. Thus, it may not be a one-way adjustment factor, but has a pleiotropic. Recent studies showed that TGF-ß1 was considered as binding to receptor and transferring signal into the cell. Now there are three different receptors are found. The classical pathway of TGF-ß1 in intracellular signal transduction is mainly through activation of Smad pathway. In the same time, there are also some non-classical pathways. TGF-ß1 could break balance of extracellular matrix, which may be a reason to cause tendinopathy. But the regulations of TGF-ß1 on the extracellular matrix are complex and diverse, further studies are required. Existing researches showed that the performance of treatments on tendinopathy is unsatisfied by blocking TGF-ß1 downstream pathway. Therefore, it is a good way to study the upstream mechanism of produce TGF-ß1. It may be an effective method to find new targets to inhibit the development of tendinopathy better by finding the original source of TGF-ß1.

Identification of novel rice (Oryza sativa) HPP and HIPP genes tolerant to heavy metal toxicity.

HPP (heavy metal associated plant protein) and HIPP (heavy metal associated isoprenylated plant protein) are a group of metal-binding metallochaperones playing crucial roles in metal homeostasis and detoxification. Up to now, only few of them have been functionally identified in plants. Here, we identified 54 HPP and HIPP genes in rice genome. Analysis of the transcriptome datasets of the rice genome exposed to cadmium (Cd) revealed 17 HPP/HIPP genes differentially expressed, with 11 being upregulated (>2 fold change, p < 0.05). Comprehensive analysis of transcripts by qRT-PCR showed that both types of genes displayed diverse expression pattern in rice under excess manganese (Mn), copper (Cu) and Cd stress. Multiple genomic analyses of HPPs/HIPPs including phylogenesis, conserved domains and motifs, genomic arrangement and genomic and tandem duplication were performed. To identify the role of the genes, OsHIPP16, OsHIPP34 and OsHIPP60 were randomly selected to express in yeast (Saccharomyces cerevisiae) mutants pmrl, cup2, ycf1 and zrc1, exhibiting sensitivity to Mn, Cu, Cd and Zn toxicity, respectively. Complementation test showed that the transformed cells accumulated more metals in the cells, but their growth status was improved. To confirm the functional role, two mutant oshipp42 lines defective in OsHIPP42 expression were identified under metal stress. Under normal condition, no difference of growth between the oshipp42 mutant and wild-type plants was observed. Upon excess Cu, Zn, Cd and Mn, the oshipp42 lines grew weaker than the wild-type. Our work provided a novel source of heavy metal-binding genes in rice that can be potentially used to develop engineered plants for phytoremediation in heavy metal-contaminated soils.

GntR Family Regulator DasR Controls Acetate Assimilation by Directly Repressing the acsA Gene in Saccharopolyspora erythraea.

The GntR family regulator DasR controls the transcription of genes involved in chitin and N-acetylglucosamine (GlcNAc) metabolism in actinobacteria. GlcNAc is catabolized to ammonia, fructose-6-phosphate (Fru-6P), and acetate, which are nitrogen and carbon sources. In this work, a DasR-responsive element (dre) was observed in the upstream region of acsA1 in Saccharopolyspora erythraea This gene encodes acetyl coenzyme A (acetyl-CoA) synthetase (Acs), an enzyme that catalyzes the conversion of acetate into acetyl-CoA. We found that DasR repressed the transcription of acsA1 in response to carbon availability, especially with GlcNAc. Growth inhibition was observed in a dasR-deleted mutant (ΔdasR) in the presence of GlcNAc in minimal medium containing 10 mM acetate, a condition under which Acs activity is critical to growth. These results demonstrate that DasR controls acetate assimilation by directly repressing the transcription of the acsA1 gene and performs regulatory roles in the production of intracellular acetyl-CoA in response to GlcNAc.IMPORTANCE Our work has identified the DasR GlcNAc-sensing regulator that represses the generation of acetyl-CoA by controlling the expression of acetyl-CoA synthetase, an enzyme responsible for acetate assimilation in S. erythraea The finding provides the first insights into the importance of DasR in the regulation of acetate metabolism, which encompasses the regulatory network between nitrogen and carbon metabolism in actinobacteria, in response to environmental changes.

Opposite Effects of Two-Derived Antioxidants from Physalis pubescens L. on Hepatocellular Carcinoma Cell Line Malhavu.

Physalis pubescens L. (P. pubescens) is an edible plant used in folk medicine in China. There is traditional, but not scientific, evidence for the anti-tumour effects of P. pubescens. This study aimed to identify whether, or not, antioxidants rich in phenols and flavonoids from fruits and calyxes of P. pubescens can be the candidates for further development of an anti-hepatoma fraction, and if such biological effects coupled with reactive oxygen species (ROS) changes, can provide a direction for subsequent biological action. The effects of calyx-origin (or fruit-origin) total phenol and flavonoid (CTPF or FTPF) from P. pubescens on Malhavu cell viability were evaluated by using a counting-kit-8 (CCK-8) method. Morphological characterisation of cells was undertaken and the structures were photographed (200 × magnification) using Hoechst 3348 staining after exposure to different concentrations of CTPF or FTPF. Induced-apoptosis activity was determined using flow cytometry (FC) after Annexin VFITC/ PI staining. The corresponding ROS changes in Malhavu cells were observed and quantified by the uploading of 2', 7'-dichlorofluorescin diacetate (DCFH-DA). Anti-oxidation was evaluated by a cellular oxidation-stress model and chemical assessments for DPPH, hydroxyl radial, super-oxide radicals, and reducing power. Result shows that CTPF led to significant anti-proliferation in a time- and dosedependent manner. However, FTPF promoted cell viability at 100-1000 µg/mL with a dose-response manner in 24 h. With the extension of exposure time to 48 h, the cell viability did not increase with the growth of FTPF. Morphological characterisation and FC assay both demonstrated that CTPF, and not FTPF possessed induced-apoptotic activity. CTPF potentially induced cell apoptosis by promoting oxidative stress. FTPF indicated pro-oxidation at a concentration of 10 µg/mL and anti-oxidation capabilities at higher concentrations. ROS scavenging assay by oxidation-stress model indicated that CTPF (10 - 400 µg/mL) had ROS inhibitory capacity (R2 = 0.5156, p < 0.0001). FTPF (10 - 100 µg/mL) boosted the level of ROS (p < 0.0001) and inhibited the generation of ROS at 100-400 µg/mL (R2 = 0.5951, p < 0.0001). CTPF is a potential candidate requiring further exploration for the development of antihepatoma ingredients. The down-regulation of cell viability was related to production and reduction of cellular ROS.