Proteasomal degradation resolves competition between cell polarization and cellular wound healing.

Cellular wound healing, enabling the repair of membrane damage, is ubiquitous in eukaryotes. One aspect of the wound healing response is the redirection of a polarized cytoskeleton and the secretory machinery to the damage site. Although there has been recent progress in identifying conserved proteins involved in wound healing, the mechanisms linking these components into a coherent response are not defined. Using laser damage in budding yeast, we demonstrate that local cell wall/membrane damage triggers the dispersal of proteins from the site of polarized growth, enabling their accumulation at the wound. We define a protein-kinase-C-dependent mechanism that mediates the destruction of the formin Bni1 and the exocyst component Sec3. This degradation is essential to prevent competition between the site of polarized growth and the wound. Mechanisms to overcome competition from a pre-existing polarized cytoskeleton may be a general feature of effective wound healing in polarized cells.

FMRP Long-Range Transport and Degradation Are Mediated by Dynlrb1 in Sensory Neurons.

The fragile X messenger ribonucleoprotein 1 (FMRP) is a multifunctional RNA-binding protein implicated in human neurodevelopmental and neurodegenerative disorders. FMRP mediates the localization and activity-dependent translation of its associated mRNAs through the formation of phase-separated condensates that are trafficked by microtubule-based motors in axons. Axonal transport and localized mRNA translation are critical processes for long-term neuronal survival and are closely linked to the pathogenesis of neurological diseases. FMRP dynein-mediated axonal trafficking is still largely unexplored but likely to constitute a key process underlying FMRP spatiotemporal translational regulation. Here, we show that dynein light chain roadblock 1 (Dynlrb1), a subunit of the dynein complex, is a critical regulator of FMRP function. In sensory axons, FMRP associates with endolysosomal organelles, likely through annexin A11, and is retrogradely trafficked by the dynein complex in a Dynlrb1-dependent manner. Moreover, Dynlrb1 silencing induced FMRP granule accumulation and repressed the translation of microtubule-associated protein 1b, one of its primary mRNA targets. Our findings suggest that Dynlrb1 regulates FMRP function through the control of its transport and targeted degradation.

Clathrin-mediated trafficking of phospholipid flippases is required for local plasma membrane/cell wall damage repair in budding yeast.

Plasma membrane damage and repair frequently happen in cells. A critical process underlying plasma membrane repair is to redirect repair factors, such as protein kinase C and the exocyst complex, from the polarized site to the damage site. However, the mechanism underlying the repair factor delivery to the damage site remains unknown. Here, we demonstrate that clathrin-mediated trafficking of repair factors is involved in plasma membrane/cell wall repair in budding yeast. Using laser-induced plasma membrane/cell wall damage assay, we identified phospholipid flippases, Lem3-Dnf1/Dnf2 and Cdc50-Drs2, as essential clathrin cargos for plasma membrane/cell wall repair. We found that flippase impairment significantly compromised the recruitment of exocyst Exo70 to the damage site. In contrast, the recruitment of protein kinase C (Pkc1) was only mildly compromised. Taken together, clathrin-mediated trafficking of the phospholipid flippases is critical for the recruitment of exocyst to the damage site. Mechanisms to redirect exocyst via the clathrin and flippase-mediated pathways may be a general feature of effective plasma membrane repair in polarized cells.

Ypk1 and Ypk2 kinases maintain Rho1 at the plasma membrane by flippase-dependent lipid remodeling after membrane stresses.

The plasma membrane (PM) is frequently challenged by mechanical stresses. In budding yeast, TORC2-Ypk1/Ypk2 kinase cascade plays a crucial role in PM stress responses by reorganizing the actin cytoskeleton via Rho1 GTPase. However, the molecular mechanism by which TORC2-Ypk1/Ypk2 regulates Rho1 is not well defined. Here, we found that Ypk1/Ypk2 maintain PM localization of Rho1 under PM stress via spatial reorganization of the lipids including phosphatidylserine. Genetic evidence suggests that this process is mediated by the Lem3-containing lipid flippase. We propose that lipid remodeling mediated by the TORC2-Ypk1/Ypk2-Lem3 axis is a backup mechanism for PM anchoring of Rho1 after PM stress-induced acute degradation of phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2], which is responsible for Rho1 localization under normal conditions. Since all the signaling molecules studied here are conserved in higher eukaryotes, our findings might represent a general mechanism to cope with PM stress.

A new cell cycle checkpoint that senses plasma membrane/cell wall damage in budding yeast.

In nature, cells face a variety of stresses that cause physical damage to the plasma membrane and cell wall. It is well established that evolutionarily conserved cell cycle checkpoints monitor various cellular perturbations, including DNA damage and spindle misalignment. However, the ability of these cell cycle checkpoints to sense a damaged plasma membrane/cell wall is poorly understood. To the best of our knowledge, our recent paper described the first example of such a checkpoint, using budding yeast as a model. In this review, we will discuss this important question as well as provide hypothetical explanations to be tested in the future.

Plasma membrane/cell wall perturbation activates a novel cell cycle checkpoint during G1 in Saccharomyces cerevisiae.

Cellular wound healing or the repair of plasma membrane/cell wall damage (plasma membrane damage) occurs frequently in nature. Although various cellular perturbations, such as DNA damage, spindle misalignment, and impaired daughter cell formation, are monitored by cell cycle checkpoint mechanisms in budding yeast, whether plasma membrane damage is monitored by any of these checkpoints remains to be addressed. Here, we define the mechanism by which cells sense membrane damage and inhibit DNA replication. We found that the inhibition of DNA replication upon plasma membrane damage requires GSK3/Mck1-dependent degradation of Cdc6, a component of the prereplicative complex. Furthermore, the CDK inhibitor Sic1 is stabilized in response to plasma membrane damage, leading to cell integrity maintenance in parallel with the Mck1-Cdc6 pathway. Cells defective in both Cdc6 degradation and Sic1 stabilization failed to grow in the presence of plasma membrane damage. Taking these data together, we propose that plasma membrane damage triggers G1 arrest via Cdc6 degradation and Sic1 stabilization to promote the cellular wound healing process.

Feelings about Nursing Assistants that Enhance the Work Motivation of Japanese Registered Nurses and Licensed Practical Nurses.

Registered nurses and licensed practical nurses have received professional education, but to enhance their work motivation it is necessary to create work environments in which they can concentrate on their jobs as specialists. One of the methods to develop such work environments is to use nursing assistants effectively. We investigated professional nurses' feelings toward nursing assistants and then examined the associations between those feelings and their work motivation. The analyzed subjects were 2,170 female nurses working in 25 hospitals with from 55 to 458 beds. The average age of the respondents was 38.0 (standard deviation, 10.6 years). Factor analyses extracted four factors of professional nurses' feelings toward nursing assistants: 1. knowledge related to healthcare, 2. nursing assistants' attitudes toward work, 3. human relations, and 4. distinguishing between professional nurses' work and nursing assistants' work. Using multiple linear regression analysis, our results revealed that scores of maintaining a high motivation to work thanks to nursing assistants became lower as the ages of the respondents increased. Scores of maintaining a high motivation to work thanks to nursing assistants became higher as professional nurses gained satisfaction from: knowledge related to healthcare, nursing assistants' attitudes toward work, and human relations. Hospital managers should consider these findings to improve working environments in which professional nurses can feel motivated to work.

Predictors of a Desire to be Helpful to Professional Nurses Among Japanese Nursing Assistants in Small- to Medium-Sized Hospitals.

Registered nurses and licensed practical nurses have been educated as professional nurses. Professional nurses can concentrate on their jobs requiring a high degree of expertise with help they get from nursing assistants.If professional nurses have improper attitudes toward nursing assistants, it is most likely that the nursing assistants will not help them to the best of their ability. We investigated nursing assistants' impressions regarding professional nurses' attitudes, and what effects nursing assistants' impressions have on their "desire to be helpful to professional nurses." The study design was a cross sectional study. Twenty-five small- to medium-sized hospitals with 55 to 458 beds were included in this study. The analyzed subjects were 642 nursing assistants (96 males, 546 females). Factor analyses were conducted to extract the factors of nursing assistants' impressions regarding professional nurses' attitudes. Multiple linear regression analysis was conducted to investigate the predictors of "desire to be helpful to professional nurses." We discovered 5 factors: 1. professional nurses' model behavior, 2. manner dealing with nursing assistants, 3. respect for nursing assistants' passion for their work, 4. respect for nursing assistants' work, and 5. enhancing the ability of nursing assistants to do their work. The "desire to be helpful to professional nurses" was significantly associated with "professional nurses' model behavior," "manner dealing with nursing assistants" and "respect for nursing assistants' passion for their work." Factors 1 to 3 are fundamental principles when people establish appropriate relationships. Professional nurses must consider these fundamentals in their daily work in order to get complete cooperation from nursing assistants.

Exocytic plasma membrane flows remodel endoplasmic reticulum-plasma membrane tethering for septin collar assembly.

Endoplasmic reticulum (ER)-plasma membrane (PM) tethering is crucial for the non-vesicular lipid transport between the ER membrane and the PM. However, the PM-associated ER can impede the PM binding of cytoskeletons and other organelles. It is poorly understood how the competition between the ER and cytoskeletons/organelles on the PM is resolved. Here, we show that, upon septin collar assembly, ER-PM tethering proteins are excluded from the yeast bud sites, and the PM-associated ER is locally detached from the PM. Our results suggest that PM flows by polarized exocytosis extrude PM proteins, including ER-PM tethering proteins, from the bud sites. When the reorganization of the ER-PM tethering was inhibited by exocytosis repression, septin localization was restricted to the PM sites poor in ER-PM tethering proteins. This study proposes machinery reconciling ER-septin competition on the PM, providing mechanistic insights into the spatial organization of PM-associated organelles and cytoskeletons.

[The past and future of occupational health nursing research in Japan].

OBJECTIVES: This study aimed to review the trends in "occupational health nursing research" conducted in Japan and determine research areas that need strengthening eventually. METHODS: All articles published in Ichushi Web since 1903 were searched using the keywords "occupational health nursing" and "research." The 486 papers identified were extracted and categorized according to type and publication year. The research content of 194 original and review papers was categorized according to whether they addressed practical methods and abilities. RESULTS AND DISCUSSION: According to publication type, out of the 486 papers, 230 (47.3%) were conference proceedings, whereas 194 (39.9%) were original and review papers. Among practical methods-related papers, 107 (55.2%), 86 (44.3%), and 1 (0.5%) were on general, health, and work environment management, respectively, whereas none addressed work management and occupational health education. Among practical ability-related papers, 125 (64.4%), 23 (11.9%), and 46 (23.7%) were on knowledge, technology, and competency, respectively. The overview of annual trends showed that the papers of all types have increased progressively. While conference proceedings accounted for 80% of the papers until 1992, recent proportions have shown a decrease to < 50%. Conversely, original papers accounted for < 20% of the papers early on, but observed a progressive increase, with recent proportions of > 40%. Regarding content, almost no papers addressed work environment management, work management, and occupational health education. Additionally, practical ability-related papers highlighted that although some research on technologies and competencies has been conducted, some areas remain inadequately addressed. CONCLUSIONS: In Japan, occupational health nursing papers have been steadily increasing since the first conference proceeding was published in 1980. Among papers addressing practical methods, those related to general management were most common, of which occupational health management accounted for approximately 80%, indicating efforts aimed at the development of occupational health nursing through research. Moreover, limited papers addressed work environment management, work management, and occupational health education, suggesting the need for future research. Among papers addressing practical ability, > 60% were related to knowledge, with research on competencies was only > 20%, suggesting the need for further research eventually.

Cytoplasmic zoning by protein phase transition after membrane permeabilization.

Biological membranes, including plasma membrane (PM) and organelle membranes, restrict the flux of ions, molecules and organelles. However, the barrier function of biological membranes is frequently compromised by various perturbations, including physical membrane damage and protein- or chemical-induced pore formation. Recent evidence suggests that, upon PM damage, protein gelation and solid condensation are utilized to restrict ion/molecule/organelle flux across the damaged membranes by zoning the cytoplasm. In addition, membrane permeabilization dramatically alters intramembrane and extramembrane ion/molecule concentrations via the flux across the permeabilized membrane. The changes in ion/molecule concentration and their downstream pathways induce protein phase transition to form zones for biological processes or protein sequestration. Here, we review the mechanisms and functions of protein phase transition after biological membrane permeabilization.

Plasma membrane damage limits replicative lifespan in yeast and induces premature senescence in human fibroblasts.

Plasma membrane damage (PMD) occurs in all cell types due to environmental perturbation and cell-autonomous activities. However, cellular outcomes of PMD remain largely unknown except for recovery or death. In this study, using budding yeast and normal human fibroblasts, we found that cellular senescence-stable cell cycle arrest contributing to organismal aging-is the long-term outcome of PMD. Our genetic screening using budding yeast unexpectedly identified a close genetic association between PMD response and replicative lifespan regulations. Furthermore, PMD limits replicative lifespan in budding yeast; upregulation of membrane repair factors ESCRT-III (SNF7) and AAA-ATPase (VPS4) extends it. In normal human fibroblasts, PMD induces premature senescence via the Ca2+-p53 axis but not the major senescence pathway, DNA damage response pathway. Transient upregulation of ESCRT-III (CHMP4B) suppressed PMD-dependent senescence. Together with mRNA sequencing results, our study highlights an underappreciated but ubiquitous senescent cell subtype: PMD-dependent senescent cells.

Genetic control of CCL24, POR, and IL23R contributes to the pathogenesis of sarcoidosis.

Sarcoidosis is a genetically complex systemic inflammatory disease that affects multiple organs. We present a GWAS of a Japanese cohort (700 sarcoidosis cases and 886 controls) with replication in independent samples from Japan (931 cases and 1,042 controls) and the Czech Republic (265 cases and 264 controls). We identified three loci outside the HLA complex, CCL24, STYXL1-SRRM3, and C1orf141-IL23R, which showed genome-wide significant associations (P < 5.0 × 10-8) with sarcoidosis; CCL24 and STYXL1-SRRM3 were novel. The disease-risk alleles in CCL24 and IL23R were associated with reduced CCL24 and IL23R expression, respectively. The disease-risk allele in STYXL1-SRRM3 was associated with elevated POR expression. These results suggest that genetic control of CCL24, POR, and IL23R expression contribute to the pathogenesis of sarcoidosis. We speculate that the CCL24 risk allele might be involved in a polarized Th1 response in sarcoidosis, and that POR and IL23R risk alleles may lead to diminished host defense against sarcoidosis pathogens.

Predictors of female registered nurses' interest in enrolling in master's programs of nursing graduate schools in Japan.

Objective: Enrollment in graduate schools presents a useful opportunity for registered nurses to enhance their expertise in their nursing field and gain better opportunities to achieve their desired career advancements. This study investigates the predictors associated with registered nurses' interest in enrolling in master's programs of nursing graduate schools. Materials and Methods: For the predictors associated with interest in enrolling in master's programs of nursing science, we evaluated items related to registered nurses' perceptions of their work environments and their impressions regarding master's programs in nursing. The analyzed subjects were 3,611 female registered nurses working in 30 hospitals in Mie prefecture, Japan. Multiple linear regression analyses were conducted to investigate registered nurses' predictors of interest in enrolling in master's programs of nursing graduate schools. We included the variables with Variance Inflation Factor (VIF) less than (<) 2 in the statistical model. Results: Full-time nurses were more interested in enrolling in master's programs than part-time nurses. Registered nurses who felt that they could keep up with courses in graduate schools, that they would be able to acquire skills to contribute to society, and that their colleagues were competent, showed stronger interest in master's programs. Registered nurses who were under the impression that graduate school teachers were dedicated to their students showed lower interest in master's programs. Registered nurses who felt that their superiors were competent and that they were expected to perform well by physicians also showed lower interest in master's programs. Conclusion: Predictors significantly associated with registered nurses' interest in enrolling in master's programs of nursing graduate schools were determined. Further studies are required to gain a more detailed understanding of the nurses' attitudes investigated.

Cdk1-mediated DIAPH1 phosphorylation maintains metaphase cortical tension and inactivates the spindle assembly checkpoint at anaphase.

Animal cells undergo rapid rounding during mitosis, ensuring proper chromosome segregation, during which an outward rounding force abruptly increases upon prometaphase entry and is maintained at a constant level during metaphase. Initial cortical tension is generated by the actomyosin system to which both myosin motors and actin network architecture contribute. However, how cortical tension is maintained and its physiological significance remain unknown. We demonstrate here that Cdk1-mediated phosphorylation of DIAPH1 stably maintains cortical tension after rounding and inactivates the spindle assembly checkpoint (SAC). Cdk1 phosphorylates DIAPH1, preventing profilin1 binding to maintain cortical tension. Mutation of DIAPH1 phosphorylation sites promotes cortical F-actin accumulation, increases cortical tension, and delays anaphase onset due to SAC activation. Measurement of the intra-kinetochore length suggests that Cdk1-mediated cortex relaxation is indispensable for kinetochore stretching. We thus uncovered a previously unknown mechanism by which Cdk1 coordinates cortical tension maintenance and SAC inactivation at anaphase onset.

Competencies required for occupational health nurses.

OBJECTIVES: For occupational health (OH) nurses to perform activities effectively, not only skills and knowledge but also competencies proposed by Dr. McClelland are indispensable. This study aimed to identify competencies required for OH nurses and to show their structure diagram. METHODS: Qualitative descriptive research was conducted from October 2010 to August 2011. Eight high-performing OH nurses participated, and data were collected from semi-structured interviews held for each nurse. Data were qualitatively and inductively analyzed using the KJ method. RESULTS: Seven competencies were identified: "self-growth competency," "OH nursing essence perpetuation competency," "strategic planning and duty fulfillment competency," "coordination competency," "client growth support competency," "team empowerment competency," and "creative competency." A structure diagram of the seven competencies was clarified. As the definitions of the competencies were different, the findings of competencies for OH nursing in the United States of America (USA) could not simply be compared with the findings of our study; however, all seven competencies were compatible with those in AAOHN model 1 and AAOHN model 2 in the USA. CONCLUSION: Our seven competencies are essential for OH nurses to perform activities that meet the expectations of employees and the employer.

Controlled trial of worksite health education through face-to-face counseling vs. e-mail on drinking behavior modification.

This study examined the effectiveness of a traditional face-to-face health education and e-mail health education on alcohol usage among male workers in comparison with a control group. Male workers at a manufacturing plant (N=36) who had abnormal serum gamma-GTP were stratified by age and job types, then randomized into three groups: face-to-face education, e-mail education, and the control. The subjects were assessed on their knowledge about and attitude towards drinking, reported alcohol consumption, and serum gamma-GTP before the start of education and 2 months later after comparison of the education. Paired t-test and repeated ANOVA were conducted to test the significance of changes pre and post the intervention and across groups. In the face-to-face group, knowledge (p=0.001), attitude (p=0.026), alcohol consumption (p=0.003) and serum gamma-GTP showed significant improvement. In the e-mail group, only alcohol consumption showed marginal improvement (p=0.077). In the control group, no variables remarkably changed. These results indicate that the face-to-face health education was more effective than the e-mail program. We discuss why the face-to-face approach was superior to the e-mail approach in this study by referring to self-monitoring, goal setting processes and timely feedback. We concluded that further studies are warranted to identify the effect of health education using e-mails and other network tools in consideration of the above three factors.

Local and Acute Disruption of the Yeast Cell Surface.

In nature, the yeast cell barrier encounters threats ranging from physical impact to abrupt changes in osmolality after rainfall. Genetic materials are protected from these environmental attacks by the rigid cell wall. Laboratory methods for challenging cell wall integrity have made an enormous contribution to the study of the yeast cell surface, but most have targeted whole-cell populations in place of single-cell analysis. This protocol describes pulse-laser-based acute disruption of the yeast cell surface, which enables the observation of single-cell response to submicron-scale damage.

PP1-Dependent Formin Bnr1 Dephosphorylation and Delocalization from a Cell Division Site.

Cell cycle ends with cytokinesis that is the physical separation of a cell into two daughter cells. For faithful cytokinesis, cells integrate multiple processes, such as actomyosin ring formation, contraction and plasma membrane closure, into coherent responses. Linear actin assembly by formins is essential for formation and maintenance of actomyosin ring. Although budding yeast's two formins, Bni1 and Bnr1, are known to switch their subcellular localization at the division site prior to cytokinesis, the underlying mechanisms were not completely understood. Here, we provide evidence showing that Bnr1 is dephosphorylated concomitant with its release from the division site. Impaired PP1/Glc7 activity delayed Bnr1 release and dephosphorylation, Bni1 recruitment and actomyosin ring formation at the division site. These results suggest the involvement of Glc7 in this regulation. Further, we identified Ref2 as the PP1 regulatory subunit responsible for this regulation. Taken together, Glc7 and Ref2 may have a role in actomyosin ring formation by modulating the localization of formins during cytokinesis.

Examination and Disruption of the Yeast Cell Wall.

The cell wall of Saccharomyces cerevisiae is a complicated extracellular organelle. Although the barrier may seem like a technical nuisance for researchers studying intracellular biomolecules or conditions, the rigid wall is an essential aspect of the yeast cell. Without it, yeast cells are unable to proliferate or carry out their life cycle. The chemical composition of the cell wall and the biosynthetic pathways and signal transduction mechanisms involved in cell wall remodeling have been studied extensively, but many unanswered questions remain. This introduction describes techniques for investigating abnormalities in the cell and spore walls and performing cell wall disruption.