55 research outputs found
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A creative thesis of lyric poetry. A collection exploring the struggles and beauty of childhood, relationships and desire as they play out in front of a Western Oklahoma backdrop
A Handbook for Orientation of First Year Teachers in the Walla Walla School District
The transition from student teacher to becoming a professional teacher can be a very trying experience. Research, interviews and studies were done to point out problems beginning teachers have in their first year of employment. Due to these problems, beginning teachers need to know where to go for help. Administrators, secretarial services and custodial services can be very beneficial to aid the beginning teacher in the first year of employment. The aim of this project is to create a handbook for beginning teachers in the Walla Walla School District with the research discussed
In Search of the City
Where does one find the city? Is it in a cluster of buildings, a pattern of streets, a collection of cultural amenities and civic services, or a residential neighborhood? Does it always include congestion, blight, pollution, and other manifestations of urban decay
Architecture Between the Lines: A week long design studio with Peter Eisenman
As the fall demester\u27s Ekdahl Lecture Series guest, New York architect Peter Eisenman visited Kansas State University for five days in November of 1979
A mechanism for exocyst-mediated tethering via Arf6 and PIP5K1C-driven phosphoinositide conversion
Polarized trafficking is necessary for the development of eukaryotes and is regulated by a conserved molecular machinery. Late steps of cargo delivery are mediated by the exocyst complex, which integrates lipid and protein components to tether vesicles for plasma membrane fusion. However, the molecular mechanisms of this process are poorly defined. Here, we reconstitute functional octameric human exocyst, demonstrating the basis for holocomplex coalescence and biochemically stable subcomplexes. We determine that each subcomplex independently binds to phosphatidylinositol 4,5-bisphosphate (PI(4,5)P(2)), which is minimally sufficient for membrane tethering. Through reconstitution and epithelial cell biology experiments, we show that Arf6-mediated recruitment of the lipid kinase PIP5K1C rapidly converts phosphatidylinositol 4-phosphate (PI(4)P) to PI(4,5)P(2), driving exocyst recruitment and membrane tethering. These results provide a molecular mechanism of exocyst-mediated tethering and a unique functional requirement for phosphoinositide signaling on late-stage vesicles in the vicinity of the plasma membrane
A Multi-Method Evaluation of the Implementation of a Student Response System
Student response systems (SRS) are keypad devices that allow students to provide responses to questions embedded within a lecture, which can then be used to provide real-time feedback. In the fall of 2005 a second stage pilot implementation of these devices was carried out at a Midwestern technological research University, with 417 students in large enrollment chemistry and calculus courses. The purpose of this study was to conduct an evaluation of this implementation. The research methodology included qualitative field observation and quantitative analysis of students\u27 responses to surveys. The results indicated that: a) Overall, the devices had a strong positive impact on student ratings; b) All instructors used the devices actively, and encouraged collaboration; though they differed in quizzing and collaborative practices; c) Though all instructors\u27 student ratings were high, there were significant differences that may have been mediated by these differences in practices
Recombinant biosensors for multiplex and super-resolution imaging of phosphoinositides
Phosphoinositides are a small family of phospholipids that act as signaling hubs and key regulators of cellular function. Detecting their subcellular distribution is crucial to gain insights into membrane organization and is commonly done by the overexpression of biosensors. However, this leads to cellular perturbations and is challenging in systems that cannot be transfected. Here, we present a toolkit for the reliable, fast, multiplex, and super-resolution detection of phosphoinositides in fixed cells and tissue, based on recombinant biosensors with self-labeling SNAP tags. These are highly specific and reliably visualize the subcellular distributions of phosphoinositides across scales, from 2D or 3D cell culture to Drosophila tissue. Further, these probes enable super-resolution approaches, and using STED microscopy, we reveal the nanoscale organization of PI(3)P on endosomes and PI(4)P on the Golgi. Finally, multiplex staining reveals an unexpected presence of PI(3,5)P2-positive membranes in swollen lysosomes following PIKfyve inhibition. This approach enables the versatile, high-resolution visualization of multiple phosphoinositide species in an unprecedented manner.</p
Recombinant biosensors for multiplex and super-resolution imaging of phosphoinositides
Phosphoinositides are a small family of phospholipids that act as signaling hubs and key regulators of cellular function. Detecting their subcellular distribution is crucial to gain insights into membrane organization and is commonly done by the overexpression of biosensors. However, this leads to cellular perturbations and is challenging in systems that cannot be transfected. Here, we present a toolkit for the reliable, fast, multiplex, and super-resolution detection of phosphoinositides in fixed cells and tissue, based on recombinant biosensors with self-labeling SNAP tags. These are highly specific and reliably visualize the subcellular distributions of phosphoinositides across scales, from 2D or 3D cell culture to Drosophila tissue. Further, these probes enable super-resolution approaches, and using STED microscopy, we reveal the nanoscale organization of PI(3)P on endosomes and PI(4)P on the Golgi. Finally, multiplex staining reveals an unexpected presence of PI(3,5)P2-positive membranes in swollen lysosomes following PIKfyve inhibition. This approach enables the versatile, high-resolution visualization of multiple phosphoinositide species in an unprecedented manner.</p
A PI(3,5)P2 reporter reveals PIKfyve activity and dynamics on macropinosomes and phagosomes
Phosphoinositide signaling lipids (PIPs) are key regulators of membrane identity and trafficking. Of these, PI(3,5)P2 is one of the least well-understood, despite key roles in many endocytic pathways including phagocytosis and macropinocytosis. PI(3,5)P2 is generated by the phosphoinositide 5-kinase PIKfyve, which is critical for phagosomal digestion and antimicrobial activity. However PI(3,5)P2 dynamics and regulation remain unclear due to lack of reliable reporters. Using the amoeba Dictyostelium discoideum, we identify SnxA as a highly selective PI(3,5)P2-binding protein and characterize its use as a reporter for PI(3,5)P2 in both Dictyostelium and mammalian cells. Using GFP-SnxA, we demonstrate that Dictyostelium phagosomes and macropinosomes accumulate PI(3,5)P2 3 min after engulfment but are then retained differently, indicating pathway-specific regulation. We further find that PIKfyve recruitment and activity are separable and that PIKfyve activation stimulates its own dissociation. SnxA is therefore a new tool for reporting PI(3,5)P2 in live cells that reveals key mechanistic details of the role and regulation of PIKfyve/PI(3,5)P
A ruthenium(II) polypyridyl complex disrupts actin cytoskeleton assembly and blocks cytokinesis
The dinuclear RuII complex [(Ru(phen)2)2(tpphz)]4+ (phen=1,10-phenanthroline, tpphz=tetrapyridophenazine) “RuRuPhen” blocks the transformation of G-actin monomers to F-actin filaments with no disassembly of pre-formed F-actin. Molecular docking studies indicate multiple RuRuPhen molecules bind to the surface of G-actin but not the binding pockets of established actin polymerisation inhibitors. In cells, addition of RuRuPhen causes rapid disruption to actin stress fibre organisation, compromising actomyosin contractility and cell motility; due to this effect RuRuPhen interferes with late-stage cytokinesis. Immunofluorescent microscopy reveals that RuRuPhen causes cytokinetic abscission failure by interfering with endosomal sorting complexes required for transport (ESCRT) complex recruitment
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