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More than 100 proteins necessary for eukaryotic cell growth, differentiation, and morphology require posttranslational modification by the covalent attachment of an isoprenoid lipid (prenylation). Prenylated proteins include members of the Ras, Rab, and Rho families, lamins, CENPE and CENPF, and the γ subunit of many small heterotrimeric G proteins. This modification is catalyzed by the protein prenyltransferases: protein farnesyltransferase (FTase), protein geranylgeranyltransferase type I (GGTase-I), and GGTase-II (or RabGGTase). In this review, we examine the structural biology of FTase and GGTase-I (the CaaX prenyltransferases) to establish a framework for understanding the molecular basis of substrate specificity and mechanism. These enzymes have been identified in a number of species, including mammals, fungi, plants, and protists. Prenyltransferase structures include complexes that represent the major steps along the reaction path, as well as a number of complexes with clinically relevant inhibitors. Such complexes may assist in the design of inhibitors that could lead to treatments for cancer, viral infection, and a number of deadly parasitic diseases.

More than 100 proteins necessary for eukaryotic cell growth, differentiation, and morphology require posttranslational modification by the covalent attachment of an isoprenoid lipid (prenylation). Prenylated proteins include members of the Ras, Rab, and Rho families, lamins, CENPE and CENPF, and the γ subunit of many small heterotrimeric G proteins. This modification is catalyzed by the protein prenyltransferases: protein farnesyltransferase (FTase), protein geranylgeranyltransferase type I (GGTase-I), and GGTase-II (or RabGGTase). In this review, we examine the structural biology of FTase and GGTase-I (the CaaX prenyltransferases) to establish a framework for understanding the molecular basis of substrate specificity and mechanism. These enzymes have been identified in a number of species, including mammals, fungi, plants, and protists. Prenyltransferase structures include complexes that represent the major steps along the reaction path, as well as a number of complexes with clinically relevant inhibitors. Such complexes may assist in the design of inhibitors that could lead to treatments for cancer, viral infection, and a number of deadly parasitic diseases.

A method is described for using a photosimulation laboratory environment to evaluate the effectiveness of camouflage for military vehicles. There are distinct advantages to acquiring images at the field site and then bringing them back to a laboratory environment for observer testing versus taking the subjects out to the field for estimating detection probability. Laboratory testing using field-acquired imagery provides a repeatable, secure, and relatively low-cost way to generate consistent data for the measurement of the effectiveness of camouflage relative to a baseline vehicle, and the calibration and validation of target acquisition models. A laboratory test procedure is described in which a baseline light armored vehicle (LAV) is compared to a treated LAV in the Tank-Automotive and Armaments Command (TACOM) Visual Perception Laboratory (VPL) using imagery collected from the field in the manner prescribed by an experimental design. © 2003 Society of Photo-Optical Instrumentation Engineers.

This paper describes the experimental apparatus and analysis techniques now in place at the US Army Tank-automotive and Armaments COMmand Visual Perception Lab in Warren, Michigan, and the results of some preliminary trials using these methods. The tools will be used to develop and analyse experiments to better understand how drivers use various displays and viewing systems intended to aid drivers in poor visibility conditions, particularly at night. Visible and infrared road scene imagery obtained from the field were displayed simultaneously and subject eye fixation and point of gaze measured using a magnetic head tracker and near infrared eyetracker. Results were analysed to determine if personal differences between the various subjects caused them to prefer one display to another. The goal was to see if people prefer to use the heads up display or the direct view for driving at night.

There are four known isoforms of the human leptin receptor (HLR) with different C-terminal cytoplasmic domains (designated by the number of unique C-terminal amino acids). In cells expressing HLR-5, -15, or -274, 15–25% of the leptin binding sites were located at the plasma membrane. In contrast, in cells expressing HLR-67, only 5% of the total binding sites were at the plasma membrane. Immunofluorescent microscopy showed that all four isoforms partially co-localized with calnexin and β-COP, markers of the endoplasmic reticulum and the Golgi, respectively. All isoforms were also detected in an unidentified punctate compartment. All isoforms were internalized via clathrin-mediated endocytosis, but at different rates. After 20 min at 37 °C, 45% of a bound cohort of labeled ligand had been internalized by HLR-15, 30% by HLR-67, 25% by HLR-274, and 15% by HLR-5. Degradation of internalized leptin occurred in lysosomes. Overnight exposure to leptin down-regulated all isoforms, but to a variable extent. HLR-274 displayed the greatest down-regulation and also appeared to reach lysosomes more quickly than the other isoforms. The faster degradation of HLR-274 may help to terminate leptin signaling.

Persons excluded due to ethnicity or race (PEERs) leave STEM at disproportionate rates; therefore, efforts to engage undergraduate PEERs are critical to creating a diverse STEM workforce. Through a Howard Hughes Medical Institute funded Inclusive Excellence grant (HHMI-IE), the REALISE (REALizing Inclusive Science Excellence) program was developed with the goal to increase student retention and success. As part of this project, an extensive faculty development program, including a backward course design module, workshops on microaggressions and implicit bias, and teamwork training, was created to help faculty implement inclusive pedagogy strategies. There were 33 faculty members who participated in the trainings within faculty learning communities (FLCs) and were further supported with STEM-Education (STEM-Ed) reading groups, faculty mixers, minigrants, and engagement from the Center for Innovative Teaching and Learning (CITL). Evaluation of 10 faculty members’ change narratives and reflective prompts revealed that low-stakes opportunities such as STEM-Ed reading groups had the most influence for instituting learner-centered classroom practices, and the workshops on microaggressions and implicit biases prompted faculty to create opportunities to build respectful relationships with students. Here, we share lessons learned from our program evaluation so that others can successfully implement inclusive pedagogy in chemistry.

This article discusses the author's experience of volunteering at a nonprofit animal hospital in the South Pacific. The situation on the island fell far short of the scene he had imagined, with no company van as transportation and no living accommodations. He experienced a daily battle that did not seem to improve conditions on the island.

HIV-specific CD4 T cell responses during acute infection show robust cytolytic activity and correlate with a lower viral set point and better clinical outcome.