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Restricting the localization of the histone H3 variant CENP-A (Cse4 in yeast, CID in flies) to centromeres is essential for faithful chromosome segregation. Mislocalization of CENP-A leads to chromosomal instability (CIN) in yeast, fly and human cells. Overexpression and mislocalization of CENP-A has been observed in many cancers and this correlates with increased invasiveness and poor prognosis. Yet genes that regulate CENP-A levels and localization under physiological conditions have not been defined. In this study we used a genome-wide genetic screen to identify essential genes required for Cse4 homeostasis to prevent its mislocalization for chromosomal stability. We show that two Skp, Cullin, F-box (SCF) ubiquitin ligases with the evolutionarily conserved F-box proteins Met30 and Cdc4 interact and cooperatively regulate proteolysis of endogenous Cse4 and prevent its mislocalization for faithful chromosome segregation under physiological conditions. The interaction of Met30 with Cdc4 is independent of the D domain, which is essential for their homodimerization and ubiquitination of other substrates. The requirement for both Cdc4 and Met30 for ubiquitination is specifc for Cse4; and a common substrate for Cdc4 and Met30 has not previously been described. Met30 is necessary for the interaction between Cdc4 and Cse4, and defects in this interaction lead to stabilization and mislocalization of Cse4, which in turn contributes to CIN. We provide the first direct link between Cse4 mislocalization to defects in kinetochore structure and show that SCF-mediated proteolysis of Cse4 is a major mechanism that prevents stable maintenance of Cse4 at non-centromeric regions, thus ensuring faithful chromosome segregation. In summary, we have identified essential pathways that regulate cellular levels of endogenous Cse4 and shown that proteolysis of Cse4 by SCF-Met30/Cdc4 prevents mislocalization and CIN in unperturbed cells.

The serine integrase of phage A118 catalyzes integrative recombination between attP on the phage and a specific attB locus on the chromosome of Listeria monocytogenes, but it is unable to promote excisive recombination between the hybrid attL and attR sites found on the integrated prophage without assistance by a recombination directionality factor (RDF). We have identified and characterized the phage-encoded RDF Gp44, which activates the A118 integrase for excision and inhibits integration. Gp44 binds to the C-terminal DNA binding domain of integrase, and we have localized the primary binding site to be within the mobile coiled-coil (CC) motif but distinct from the distal tip of the CC that is required for recombination. This interaction is sufficient to inhibit integration, but a second interaction involving the N-terminal end of Gp44 is also required to activate excision. We provide evidence that these two contacts modulate the trajectory of the CC motifs as they extend out from the integrase core in a manner dependent upon the identities of the four att sites. Our results support a model whereby Gp44 shapes the Int-bound complexes to control which att sites can synapse and recombine.IMPORTANCE Serine integrases mediate directional recombination between bacteriophage and bacterial chromosomes. These highly regulated site-specific recombination reactions are integral to the life cycle of temperate phage and, in the case of Listeria monocytogenes lysogenized by A118 family phage, are an essential virulence determinant. Serine integrases are also utilized as tools for genetic engineering and synthetic biology because of their exquisite unidirectional control of the DNA exchange reaction. Here, we identify and characterize the recombination directionality factor (RDF) that activates excision and inhibits integration reactions by the phage A118 integrase. We provide evidence that the A118 RDF binds to and modulates the trajectory of the long coiled-coil motif that extends from the large carboxyl-terminal DNA binding domain and is postulated to control the early steps of recombination site synapsis.

Retrotransposition of the budding yeast long terminal repeat retrotransposon Ty3 is activated during mating. In this study, proteins that associate with Ty3 Gag3 capsid protein during virus-like particle (VLP) assembly were identified by mass spectrometry and screened for roles in mating-stimulated retrotransposition. Components of RNA processing bodies including DEAD box helicases Dhh1/DDX6 and Ded1/DDX3, Sm-like protein Lsm1, decapping protein Dcp2, and 5' to 3' exonuclease Xrn1 were among the proteins identified. These proteins associated with Ty3 proteins and RNA, and were required for formation of Ty3 VLP retrosome assembly factories and for retrotransposition. Specifically, Dhh1/DDX6 was required for normal levels of Ty3 genomic RNA, and Lsm1 and Xrn1 were required for association of Ty3 protein and RNA into retrosomes. This role for components of RNA processing bodies in promoting VLP assembly and retrotransposition during mating in a yeast that lacks RNA interference, contrasts with roles proposed for orthologous components in animal germ cell ribonucleoprotein granules in turnover and epigenetic suppression of retrotransposon RNAs.

Performance improvement (PI) team members and leaders can use a variety of tools to help accelerate change and sustain performance for lasting success. Key factors for PI team members to consider for change management are the ability to work together to problem solve and the involvement of the project's champion or sponsor for the duration of the project. The PI team can use the Change Acceleration Process model, which includes the Threats & Opportunities Matrix; backward imaging; and the goals, roles, processes, and interpersonal relationships checklist to accelerate and maintain their improvement efforts. After reviewing this article, the reader should have a better understanding of how to use the Change Acceleration Process model and tools to promote teamwork, recognize external factors that may hinder improvement, and stay focused on the project goals for ultimate PI project success. This is the sixth article of a six‐part series about performance improvement. [ABSTRACT FROM AUTHOR]

This article discusses some of the tools and tips to sustain performance improvement (PI) and explores some of the reasons why PI projects may fail. Although some PI projects seem simple and easy to implement, PI team members sometimes find it difficult to keep momentum going, maintain gains, and sustain the changes when the project is nearing completion and afterward. Team member and leader discipline, including use of multidisciplinary communication and standard work processes, can facilitate ongoing improvement. Communication may include visual displays of information and routine huddles. After reviewing this article, the reader should have a better understanding of sustaining change and promoting continuous PI. This is the fifth article of a six‐part series about PI. [ABSTRACT FROM AUTHOR]

This article discusses the process of Failure Mode and Effects Analysis (FMEA) and how it relates to performance improvement (PI) and the development of high reliability organizations. As a proactive process, PI team members can use FMEA to identify and prioritize risk before errors occur in health care environments. This tool comprises steps to assess the failure risk of a process, system, or function before the failure occurs. Performance improvement team members can use FMEA as an additional tool to guide them when working to create a culture of safe patient care and improve patient outcomes. After reviewing this article, the reader should have a better understanding of FMEA, how to implement it, and how it supports PI processes and high reliability organizations. This is the fourth article of a six‐part series about performance improvement. [ABSTRACT FROM AUTHOR]

This article discusses performance improvement (PI) and the various methods that PI teams can use to provide a framework for improvement. Teams that complete successful PI projects use a systematic methodology that guides them through the process in a step‐by‐step manner, with each step building upon the previous one using data collection methods and analytics. Personnel involved with PI projects may need to use various methodologies to achieve improvement. These tools range from Plan‐Do‐Study‐Act cycles to more complex methods such as Six Sigma, which uses a define, measure, analyze, improve, and control process as its foundation. This article includes examples of how PI project team members can implement various methodologies and analysis tools to improve processes across the PI project continuum. After reviewing this article, the reader should have a better understanding of the systematic methodologies supporting the PI process. This is the third article of a six‐part series about performance improvement. [ABSTRACT FROM AUTHOR]

This article discusses performance improvement (PI) data collection processes and the various tools that can be used to analyze and display data through the duration of a PI project. It describes the importance of data, how to determine the required amount of data, how to collect and analyze data, and in what format data should be presented. Personnel involved with PI projects may need to use various data collection methods and tools to ensure an effective project with a successful outcome. This article includes examples of how PI project team members can implement various data collection and analysis tools. After reviewing this article, the reader should have a better understanding of this part of the PI process. [ABSTRACT FROM AUTHOR]

This article discusses the history and background of performance improvement (PI) processes and describes the creation of the foundational document for a PI project: the project charter. It is important for PI teams to create a complete charter before the project begins to give structure to the project. Teams involved in PI should use the charter as a roadmap for project completion because it helps to keep the team focused on issues within the scope of the project. This article reviews the steps to begin creating the charter and provides examples of the various sections that should be included. By reviewing this article, the reader should have a better understanding of this part of the PI process. [ABSTRACT FROM AUTHOR]

The article considers the economic background of labor disputes in the motion picture industry in the U.S. These disputes are basically jurisdictional contested by the International Alliance of Theatrical Stage Employees and the various unions of building trades affiliated with the American Federation of Labor, especially concerning construction works. This situation is complicated by an increasing maladjustment between labor supply and demand. Add to this is the lack of willingness on the part of unions to settle the jurisdictional disputes except on their own terms.

A CLINICAL ANALYSIS of surgeons' preference cards was initiated in onem hospital as part of a comprehensive analysis to reduce medication-error risks by standardizing and simplifying the intraoperative medication-use process specific to the sterile field. THE PREFERENCE CARD ANALYSIS involved two subanalyses: a review of the information as it appeared on the cards and a failure mode and effects analysis of the process involved in using and maintaining the cards. THE ANALYSIS FOUND that the preference card system in use at this hospital is outdated. Variations and inconsistencies within the preference card system indicate that the use of preference cards as guides for medication selection for surgical procedures presents an opportunity for medication errors to occur [ABSTRACT FROM AUTHOR]