Ignite: More Experience, Less Expense: Meaningful and Budget-Friendly Rewards (Group 1)

For a PBIS acknowledgement system to work effectively, there must be student buy-in, which involves getting student input and implementing incentives that are meaningful and enticing to them. However, this isn’t always easy to do without breaking the bank or losing valuable instructional time! At our elementary school, we decided to focus on monthly incentives that were cost-effective and more of an experience rather than tangible (and often costly) rewards. We made sure to consider multiple factors, including (1) how to implement incentives while still maximizing instructional time for all content areas, (2) making sure all students had opportunities to participate in some way, and (3) modifying our incentives so that we can meet individual students’ needs based on RTI data, behavior plans, etc. This workshop will provide participants with the tools they need to develop student-focused incentives while working within a budget, or even no budget at all

Determinants of Homodimerization Specificity in Histidine Kinases

Two-component signal transduction pathways consisting of a histidine kinase and a response regulator are used by prokaryotes to respond to diverse environmental and intracellular stimuli. Most species encode numerous paralogous histidine kinases that exhibit significant structural similarity. Yet in almost all known examples, histidine kinases are thought to function as homodimers. We investigated the molecular basis of dimerization specificity, focusing on the model histidine kinase EnvZ and RstB, its closest paralog in Escherichia coli. Direct binding studies showed that the cytoplasmic domains of these proteins each form specific homodimers in vitro. Using a series of chimeric proteins, we identified specificity determinants at the base of the four-helix bundle in the dimerization and histidine phosphotransfer domain. Guided by molecular coevolution predictions and EnvZ structural information, we identified sets of residues in this region that are sufficient to establish homospecificity. Mutating these residues in EnvZ to the corresponding residues in RstB produced a functional kinase that preferentially homodimerized over interacting with EnvZ. EnvZ and RstB likely diverged following gene duplication to yield two homodimers that cannot heterodimerize, and the mutants we identified represent possible evolutionary intermediates in this process.National Institutes of Health (U.S.) (Award GM067681)National Science Foundation (U.S.) (CAREER Grant)National Science Foundation (U.S.). Graduate Research Fellowshi

Physiological Demands of Common Occupational Tasks among Australian Police Offcers: A Descriptive Analysis

OBJECTIVES: The aim of this study was to investigate the physiological demands placed on Australian police officers carrying out common operational tasks. METHODS: Forty participants (n = 40) from an Australian police force (mean age = 33.58 ± 7.78 years, mean height = 177.70 ± 7.28 cm, mean weight = 85.68 ± 14.52 kg, mean years of service: 6.74 ± 6.29 years) were recruited through preidentified local area commands. Spanning nine police stations from the same Australian state, volunteers wore monitoring devices to collect physiological measures (heart rate, respiratory rate, and skin temperature) throughout the course of four consecutive shifts (two day shifts and two night shifts). Descriptive data were recorded and analyzed by task and changes in physiological measures. RESULTS: Of the 345 duty calls attended by participants, the four most commonly reported tasks were as follows: ‘check bona fides’ (n = 76; 22%), ‘driving urgently’ (n = 45; 13%), ‘attending a domestic incident’ (n = 37; 10%), and ‘attending a concern for welfare’ (n = 30; 8%). Mean percentages of maximum heart rates (%HR(max)) were considered of very light exercise intensity and ranged from 47.11 (± 7.18) to 50.15 (± 9.35) % for checking bona fides through to driving urgently respectively. Fifteen percent of tasks attended had officers exceed 100 %HR(max) (near maximal to maximal exercise intensity). Mean skin temperatures varied little (36.02–36.27°C) between tasks, while mean respiratory rates were lowest when attending a domestic incident and highest when driving urgently (22.56 ± 3.83 and 24.72 ± 6.12 breaths/min, respectively). CONCLUSION: Police officers experienced numerous physiological challenges ranging from an intensity of very light exercise through to near maximal and maximal exercise throughout their working day with occasions where their heart rates exceeded 100 %HR(max). These findings highlight the physiological stress associated with common occupational policing tasks, highlighting the importance of cardiovascular health in police officers and the need for cardiovascular monitoring and conditioning

Correction: Membranes Linked by Trans-Snare Complexes Require Lipids Prone to Non-Bilayer Structure for Progression to Fusion

Like other intracellular fusion events, the homotypic fusion of yeast vacuoles requires a Rab GTPase, a large Rab effector complex, SNARE proteins which can form a 4-helical bundle, and the SNARE disassembly chaperones Sec17p and Sec18p. In addition to these proteins, specific vacuole lipids are required for efficient fusion in vivo and with the purified organelle. Reconstitution of vacuole fusion with all purified components reveals that high SNARE levels can mask the requirement for a complex mixture of vacuole lipids. At lower, more physiological SNARE levels, neutral lipids with small headgroups that tend to form non-bilayer structures (phosphatidylethanolamine, diacylglycerol, and ergosterol) are essential. Membranes without these three lipids can dock and complete trans -SNARE pairing but cannot rearrange their lipids for fusion

Sec17 Can Trigger Fusion of Trans-SNARE Paired Membranes without Sec18

Sec17 [soluble N-ethylmaleimide-sensitive factor (NSF) attachment protein; α-SNAP] and Sec18 (NSF) perform ATP-dependent disassembly of cis-SNARE complexes, liberating SNAREs for subsequent assembly of trans-complexes for fusion. A mutant of Sec17, with limited ability to stimulate Sec18, still strongly enhanced fusion when ample Sec18 was supplied, suggesting that Sec17 has additional functions. We used fusion reactions where the four SNAREs were initially separate, thus requiring no disassembly by Sec18. With proteoliposomes bearing asymmetrically disposed SNAREs, tethering and trans-SNARE pairing allowed slow fusion. Addition of Sec17 did not affect the levels of trans-SNARE complex but triggered sudden fusion of trans-SNARE paired proteoliposomes. Sec18 did not substitute for Sec17 in triggering fusion, but ADP- or ATPγS-bound Sec18 enhanced this Sec17 function. The extent of the Sec17 effect varied with the lipid headgroup and fatty acyl composition of the proteoliposomes. Two mutants further distinguished the two Sec17 functions: Sec17(L291A,L292A) did not stimulate Sec18 to disassemble cis-SNARE complex but triggered the fusion of trans-SNARE paired membranes. Sec17(F21S,M22S), with diminished apolar character to its hydrophobic loop, fully supported Sec18-mediated SNARE complex disassembly but had lost the capacity to stimulate the fusion of trans-SNARE paired membranes. To model the interactions of SNARE-bound Sec17 with membranes, we show that Sec17, but not Sec17(F21S,M22S), interacted synergistically with the soluble SNARE domains to enable their stable association with liposomes. We propose a model in which Sec17 binds to trans-SNARE complexes, oligomerizes, and inserts apolar loops into the apposed membranes, locally disturbing the lipid bilayer and thereby lowering the energy barrier for fusion

Yeast Vacuolar HOPS, Regulated by its Kinase, Exploits Affinities for Acidic Lipids and Rab:GTP for Membrane Binding and to Catalyze Tethering and Fusion

Fusion of yeast vacuoles requires the Rab GTPase Ypt7p, four SNAREs (soluble N-ethylmaleimide–sensitive factor attachment protein receptors), the SNARE disassembly chaperones Sec17p/Sec18p, vacuolar lipids, and the Rab-effector complex HOPS (homotypic fusion and vacuole protein sorting). Two HOPS subunits have direct affinity for Ypt7p. Although vacuolar fusion has been reconstituted with purified components, the functional relationships between individual lipids and Ypt7p:GTP have remained unclear. We now report that acidic lipids function with Ypt7p as coreceptors for HOPS, supporting membrane tethering and fusion. After phosphorylation by the vacuolar kinase Yck3p, phospho-HOPS needs both Ypt7p:GTP and acidic lipids to support fusion