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The integrated stress response (ISR) plays a pivotal role in adaptation of translation machinery to cellular stress. Here, we demonstrate an ISR-independent osmoadaptation mechanism involving reprogramming of translation via coordinated but independent actions of mTOR and plasma membrane amino acid transporter SNAT2. This biphasic response entails reduced global protein synthesis and mTOR signaling followed by translation of SNAT2. Induction of SNAT2 leads to accumulation of amino acids and reactivation of mTOR and global protein synthesis, paralleled by partial reversal of the early-phase, stress-induced translatome. We propose SNAT2 functions as a molecular switch between inhibition of protein synthesis and establishment of an osmoadaptive translation program involving the formation of cytoplasmic condensates of SNAT2-regulated RNA-binding proteins DDX3X and FUS. In summary, we define key roles of SNAT2 in osmotolerance., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

The mode of transmission of signals between plant cells is an important aspect of plant physiology. The main role in the generation of long-distance signals is played by changes in the membrane potential and cytoplasm calcium concentration, but the relationship between these responses evoked by the same stimuli in the same plant remains unknown. As one of the first plants that colonized land, the moss Physcomitrella patens is a suitable model organism for studying the evolution of signaling pathways in plants. Here, by the application of glutamate as a stimulus, we demonstrated that electrical but not calcium signals can be true carriers of information in long-distance signaling in Physcomitrella. The generation of electrical signals in a form of propagating transient depolarization seems to be dependent on the opening of calcium channels since the responses were reduced or totally blocked by calcium channel inhibitors. While the microelectrode measurements demonstrated the transmission of electric signals between leaf cells and juvenile cells (protonema), the fluorescence imaging of cytoplasmic calcium changes indicated that calcium response occurs only locally-at the site of glutamate application, and only in protonema cells. This study indicates different involvement of glutamate-induced electrical and calcium signals in cell-to-cell communication in these evolutionarily old terrestrial plants., (© The Author(s) 2020. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Although a lot of effort has been put into the search for factors responsible for aging in yeast mother cells, our knowledge of cellular changes in daughter cells originating from old mothers is still very limited. It has been shown that an old mother is not able to compensate for all negative changes within its cell and therefore transfers them to the bud. In this paper, we show for the first time that daughter cells of an old mother have a reset lifespan expressed in units of time despite drastic reduction of their budding lifespan, which suggests that a single yeast cell has a fixed programmed longevity regardless of the time point at which it was originated. Moreover, in our study we found that longevity parameters are not correlated with the rDNA level, DNA damage, chromosome structure or aging parameters (budding lifespan and total lifespan).

Despite many controversies, the yeast Saccharomyces cerevisiae continues to be used as a model organism for the study of aging. Numerous theories and hypotheses have been created for several decades, yet basic mechanisms of aging have remained unclear. Therefore, the principal aim of this work is to propose a possible mechanism leading to increased longevity in yeast. In this paper, we suggest for the first time that there is a link between decreased metabolic activity, fertility and longevity expressed as time of life in yeast. Determination of reproductive potential and total lifespan with the use of fob1Δ and sfp1Δ mutants allows us to compare the "longevity" presented as the number of produced daughters with the longevity expressed as the time of life. The results of analyses presented in this paper suggest the need for a change in the definition of longevity of yeast by taking into consideration the time parameter. The mutants that have been described as "long-lived" in the literature, such as the fob1Δ mutant, have an increased reproductive potential but live no longer than their standard counterparts. On the other hand, the sfp1Δ mutant and the wild-type strain produce a similar number of daughter cells, but the former lives much longer. Our results demonstrate a correlation between the decreased efficiency of the translational apparatus and the longevity of the sfp1Δ mutant. We suggest that a possible factor regulating the lifespan is the rate of cell metabolism. To measure the basic metabolism of the yeast cells, we used the isothermal microcalorimetry method. In the case of sfp1Δ, the flow of energy, ATP concentration, polysome profile and translational fitness are significantly lower in comparison with the wild-type strain and the fob1Δ mutant.

Protein Mrt4 is one of trans-acting factors involved in ribosome biogenesis, which in higher eukaryotic cells contains a C-terminal extension similar to the C-terminal part of ribosomal P proteins. We show that human Mrt4 (hMrt4/MRTO4) undergoes phosphorylation in vivo and that serines S229, S233, and S235, placed within its acidic C-termini, have been phosphorylated by CK2 kinase in vitro. Such modification does not alter the subcellular distribution of hMrt4 in standard conditions but affects its molecular behavior during ActD induced nucleolar stress. Thus, we propose a new regulatory element important for the stress response pathway connecting ribosome biogenesis with cellular metabolism., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The aim of the study was to assess the clinical and functional results of surgical treatment of female patients with rectal prolapse. In the period of 2003-2010, the group of 86 female patients (mean age of 67 ± 10) underwent surgery due to rectal prolapse. The group of 24 patients (27.9 %) suffered from mild anal incontinence. They were operated on with open sutured rectopexy (18 pts), Altemeier (45 pts) and Delorme procedure (23 pts). Prior to surgery and after operation, clinical and function results were obtained. The follow-up period amounted to 32 ± 11 months. In perineal approaches, we found mortality in one patient (1.4 %, Delorme) and anastomotic leak in four patients (5.9 %). The recurrence rate in the perineal group was 11.8 % (eight patients). We noted one recurrence in the rectopexy group (5.6 %). The Altemeier procedure revealed the most significant impact on the function of the anal sphincter muscles and resting pressures (42 ± 7 vs 53 ± 9 cm H2O; p = 0.0082). If anterior levatoroplasty was added, the benefits referred also to squeeze pressures (41 ± 8 vs 58 ± 9 cm H2O; p = 0.006 and 42 ± 10 vs 56 ± 9 cm H2O; p = 0.01). In the treatment of rectal prolapse, there is still no consensus about the operation of choice. Selection of the appropriate method should be based on clinical findings and patients' comorbidities to obtain maximal benefits and minimize the postoperative risk and failures.

Aim: Identification of the incidence of relaparotomy after operations for colorectal cancer and finding out factors influencing the incidence of relaparotomy and risk of mortality., Method: In the period from 2008 to 2012 the group of patients electively operated on for colorectal cancer was analysed. The database of the surgical department was reviewed retrospectively to search relaparotomies performed in perioperative period. We compared the risk of mortality and of reoperations according to clinical and demographic pre- and postoperative factors, tumour location and extend of surgery., Results: The group of 1674 patients was electively operated on for colorectal cancer and 121 (7.2%) relaparotomies were identified and analysed (77 males, 44 females, mean age of 65.1). In the whole group the risk of relaparotomy was higher in males OR 1.68; 95%CI 1.15-2.47; p = 0.008 and in patients with ASA III/IV OR 1.54; 95% CI 1.05-2.27; p = 0.027. The overall mortality rate was higher in patients after relaparotomy than after the only initial procedure 13.2% vs. 1.4%; with higher risk of mortality OR 9.78; 95%CI 4.97-19.29; p = 0.0008. The rate of anastomotic leak requiring reoperation was 2.7%. In resection procedures the incidence of reoperation was significantly higher 8.1% vs. 3.5%; p = 0.007, without any influence on mortality OR 0.7; 95%CI 0.14-3.49; p = 0.656. In reoperated patients mortality rate was the highest if the tumour was primary located in left colon than in the rectum an right colon (44.4% vs. 10.9% vs. 6.7%; p = 0.04). Anastomotic leak significantly increased the risk of mortality OR 2.95; 95%CI 1.00-8.39; p = 0.048. The risk of mortality was also higher in patients at age >65 OR 7.70; 95%CI 1.67-35.57; p = 0.009 and when ASA score was III or IV OR 5.83; 95%CI 1.58-21.60; p = 0.008., Conclusion: Patients after relaparotomy for complications of colorectal cancer surgery are at very high risk of mortality. Particularly male gender, older age, poor general condition and anastomotic complications are the risk factors of high mortality., (Copyright © 2014 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.)

A system for naming ribosomal proteins is described that the authors intend to use in the future. They urge others to adopt it. The objective is to eliminate the confusion caused by the assignment of identical names to ribosomal proteins from different species that are unrelated in structure and function. In the system proposed here, homologous ribosomal proteins are assigned the same name, regardless of species. It is designed so that new names are similar enough to old names to be easily recognized, but are written in a format that unambiguously identifies them as 'new system' names., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Ribosomal protein L12 is a two-domain protein that forms dimers mediated by its N-terminal domains. A 20-residue linker separates the N- and C-terminal domains. This linker results in a three-lobe topology with significant flexibility, known to be critical for efficient translation. Here we present an ensemble model of spatial distributions and correlation times for the domain reorientations of L12 that reconciles experimental data from small-angle x-ray scattering and nuclear magnetic resonance. We generated an ensemble of L12 conformations in which the structure of each domain is fixed but the domain orientations are variable. The ensemble reproduces the small-angle x-ray scattering data and the optimized correlation times of its reorientational eigenmodes fit the (15)N relaxation data. The ensemble model reveals intrinsic conformational properties of L12 that help explain its function on the ribosome. The two C-terminal domains sample a large volume and extend further away from the ribosome anchor than expected for a random-chain linker, indicating that the flexible linker has residual order. Furthermore, the distances between each C-terminal domain and the anchor are anticorrelated, indicating that one of them is more retracted on average. We speculate that these properties promote the function of L12 to recruit translation factors and control their activity on the ribosome., (Copyright 2010 Biophysical Society. Published by Elsevier Inc. All rights reserved.)

The eukaryotic ribosomal stalk, composed of the P-proteins, is a part of the GTPase-associated-center which is directly responsible for stimulation of translation-factor-dependent GTP hydrolysis. Here we report that yeast mutant strains lacking P1/P2-proteins show high propagation of the yeast L-A virus. Affinity-capture-MS analysis of a protein complex isolated from a yeast mutant strain lacking the P1A/P2B proteins using anti-P0 antibodies showed that the Gag protein, the major coat protein of the L-A capsid, is associated with the ribosomal stalk. Proteomic analysis revealed that the elongation factor eEF1A was also present in the isolated complex. Additionally, yeast strains lacking the P1/P2-proteins are hypersensitive to paromomycin and hygromycin B, underscoring the fact that structural perturbations in the stalk strongly influence the ribosome function, especially at the level of elongation.

Background: Topical application of growth factors to wounds has proven to be suboptimal in achieving epithelial growth and accelerating healing. We propose transfection of fibroblasts with a gene for acidic fibroblast growth factor (aFGF) which will allow continuous, local delivery of the growth factor to wounds, ulcerative lesions, or healing tissues., Methods: We utilized a pMEXneo vector containing the human aFGF gene with a secretory signal sequence from the hst/KS3 gene to obtain continuous secretion of therapeutic doses of aFGF. NIH 3T3 fibroblasts were transfected using a liposomal transfection reagent and grown in selective media., Results: Dot blot hybridization with labeled complementary DNA probes revealed the presence of plasmid DNA in transfected but not wild type fibroblasts. Intracellular concentrations of aFGF remained low in transfected cells; however, the media contained high levels (32 +/- 7 nM) of aFGF as measured by ELISA. Concentrations of aFGF capable of stimulating cell proliferation were maintained for several weeks., Conclusions: The aFGF cDNA was transcribed and translated into a functional polypeptide that is secreted from NIH 3T3 cells at physiologically significant concentrations. Stable transfection with a eukaryotic vector which induces secretion of aFGF at levels promoting cell growth holds promise for clinical application in wounds or healing tissue. Transfection could be achieved by topical or endoscopic injection of this type of vector., (Copyright 1998 Academic Press.)

A nitroalkane-oxidizing enzyme was purified to homogeneity from Neurospora crassa. The enzyme is composed of two subunits; the molecular weight of each subunit is approximately 40,000. The enzyme catalyzes the oxidation of nitroalkanes to produce the corresponding carbonyl compounds. It acts on 2-nitropropane better than on nitroethane and 1-nitropropane, and anionic forms of nitroalkanes are much better substrates than are neutral forms. The enzyme does not act on aromatic compounds. When the enzyme reaction was conducted in an 18O2 atmosphere with the anionic form of 2-nitropropane as the substrate, acetone (with a molecular mass of 60 Da) was produced. This indicates that the oxygen atom of acetone was derived from molecular oxygen, not from water; hence, the enzyme is an oxygenase. The reaction stoichiometry was 2CH3CH(NO2)CH3 + O2-->2CH3COCH3 + 2HNO2, which is identical to that of the reaction of 2-nitropropane dioxygenase from Hansenula mrakii. The reaction of the Neurospora enzyme was inhibited by superoxide anion scavengers in the same manner as that of the Hansenula enzyme. Both of these enzymes are flavoenzymes; however, the Neurospora enzyme contains flavin mononucleotide as a prosthetic group, whereas the Hansenula enzyme contains flavin adenine dinucleotide.

Proliferation of esophageal mucosal cells is important in repair of reflux-induced injury. We studied the effects of EGF, IGF-I, and IGF-I/binding protein-3 (BP-3) complex on immortalized esophageal epithelial (HET-1A) cells and searched for synergy between the growth factors. HET-1A cells were plated at 5 x 10(4) in 12 well plates. After 2 days in optimal media, they were maintained in basal media with or without the test peptides: EGF at 0.05-5 nM, IGF-I at 0.1-10 nM, IGF-I/BP-3 at 0.1-10 nM, and a combination of EGF at 5 nM and IGF-I or IGF-I/BP-3 at 1 and 10 nM. In comparison to basal media EGF and IGF-I stimulated cell proliferation over baseline at 5 and 10 nM, respectively. The combination of EGF at 5 nM and IGF-I at 1 and 10 nM worked synergistically, increasing cell counts over baseline to 10.3 +/- 0.2 and 14.6 +/- 0.8 x 10(5), respectively. The calculated additive effect of EGF and IGF-I at 1 and 10 nM individually increased cell counts to 8.2 +/- 0.2 and 10.4 +/- 0.6 x 10(5), respectively. The difference between the observed and the calculated values was significant at P < 0.05, ANOVA, Turkey test. IGF-I/BP-3 complex enhanced this synergy at low levels of IGF-I but not at 10 nM IGF-I. EGF, IGF, and IGF-I/BP-3 independently promote HET-1A proliferation. IGF and EGF in combination demonstrate synergism with potentiated interaction presumably because of their different roles in the cell cycle, EGF being a competence factor and IGF being a progression factor. This combination may have potential as a treatment for esophageal mucosal injury, and IGF-I/BP-3 may further enhance their benefit.

We have isolated the gene encoding 2-nitropropane dioxygenase from Hansenula mrakii, an FAD enzyme that catalyzes the oxygenative denitrification of various anionic nitroalkanes. The gene contained an open reading frame consisting of 1122 nucleotides corresponding to 374 amino acid residues. The protein molecular mass was estimated to be 41,466 Da, which was similar to the subunit molecular mass of the enzyme determined by SDS/PAGE. Several FAD enzymes such as D-amino acid oxidase and glucose oxidase also catalyze the oxidation of nitroalkanes as a side-reaction, although not so efficiently [Kido, T. & Soda, K. (1984) Arch. Biochem. Biophys. 234, 468-475]. However, we found no proteins in the databases (GenBank, EMBL, PIR and SWISS-PROT) which are homologous to 2-nitropropane dioxygenase of H. mrakii in primary structure. No protein motifs, including a nucleotide-binding motif, GXGXXG, were found in PROSITE, a database of biologically significant protein sites and patterns. Accordingly, 2-nitropropane dioxygenase is a new type of flavoprotein with a unique structure.