Insulin Degrading Enzyme Induces a Conformational Change in Varicella-Zoster Virus gE, and Enhances Virus Infectivity and Stability

Varicella-zoster virus (VZV) glycoprotein E (gE) is essential for virus infectivity and binds to a cellular receptor, insulin-degrading enzyme (IDE), through its unique amino terminal extracellular domain. Previous work has shown IDE plays an important role in VZV infection and virus cell-to-cell spread, which is the sole route for VZV spread in vitro. Here we report that a recombinant soluble IDE (rIDE) enhances VZV infectivity at an early step of infection associated with an increase in virus internalization, and increases cell-to-cell spread. VZV mutants lacking the IDE binding domain of gE were impaired for syncytia formation and membrane fusion. Pre-treatment of cell-free VZV with rIDE markedly enhanced the stability of the virus over a range of conditions. rIDE interacted with gE to elicit a conformational change in gE and rendered it more susceptible to proteolysis. Co-incubation of rIDE with gE modified the size of gE. We propose that the conformational change in gE elicited by IDE enhances infectivity and stability of the virus and leads to increased fusogenicity during VZV infection. The ability of rIDE to enhance infectivity of cell-free VZV over a wide range of incubation times and temperatures suggests that rIDE may be useful for increasing the stability of varicella or zoster vaccines

The Feminine Face of Racialized Violence: White Womanhood, White Women, and the Ku Klux Klan

Chartered in 1923, the Women of the Ku Klux Klan was recognized as a sanctioned branch of the KKK, complete with its own guiding constitution, by-laws, and organizational hierarchy. White women indeed served a fundamental role in both the organization’s endurance and the orchestration of its campaign of terror. However, today the most persistent cultural images of the Ku Klux Klan are imbued with a masculine sense of violence. This popular depiction of racialized violence embodied solely in a masculine form—anonymously shielded in our imaginary under a plain white hood—has expunged women’s efforts from the historical work of racialized violence, constructs a flawed and incomplete account of overt white supremacy, and constricts our ability to grapple with its more insidious feminine form. Thus, grounded in the analytic sensibility of intersectional inquiry, I interrogate the nuanced junctures of power at work with the white women who found home in the Klan, both as symbol and as rhetor, so as to seek to reveal the feminine face of racialized violence—one which I argue is very much still present today. I first situate this project in the lineage of (mis)remembrance. I argue that the pervasiveness of a collective rhetorical malewashing within our understanding of racialized violence has minimized our scholarly capacity to contend with the feminine style always already present within such violence. I then make visible this feminine face of racialized violence throughout each chapter by illuminating some of its most prominent rhetorical features on display in the selected case study of the KKK: white womanhood in peril as narrative hinge within dominant discourses promoting white supremacy; white femininity as bigoted agentic doing capable of underwriting white women’s racial identity and forming their political subjectivity by refusing the humanity of others; white women’s performance of a gendered mode of citizenship securing the racialized borders of national belonging; and white women’s affective work tying white supremacy’s past to present and present to future

Perfectionism and the Disclosure of Distress

Perfectionistic concerns about the discrepancy between one\u27s standards and performance are associated with several problematic interpersonal and emotional outcomes. The degree to which discrepancy as a form of perfectionism, as well as personal standards as a form of perfectionism, relate to one\u27s willingness to talk about one\u27s distress to others have been underexplored. Our study examined the association between perfectionism and distress disclosure tendencies and also anticipated disclosure in response to several stressful, hypothetical events. College students (N = 325) completed measures via an online survey. Regression analyses revealed that discrepancy (but not personal standards) was negatively related to distress disclosure tendencies. Multilevel modeling indicated that discrepancy was associated with lower anticipated disclosure of negative, hypothetical events, but discrepancy did not interact with the intensity of the event. This research provides novel findings concerning the association between discrepancy and emotional disclosure, and it suggests that personal standards has a minimal role in the disclosure of distress

Substrate-Triggered Exosite Binding: Synergistic Dendrimer/Folic Acid Action for Achieving Specific, Tight-Binding to Folate Binding Protein

Polymer–ligand conjugates are designed to bind proteins for applications as drugs, imaging agents, and transport scaffolds. In this work, we demonstrate a folic acid (FA)-triggered exosite binding of a generation five poly­(amidoamine) (G5 PAMAM) dendrimer scaffold to bovine folate binding protein (bFBP). The protein exosite is a secondary binding site on the protein surface, separate from the FA binding pocket, to which the dendrimer binds. Exosite binding is required to achieve the greatly enhanced binding constants and protein structural change observed in this study. The G5_Ac-COG-FA_1.0 conjugate bound tightly to bFBP, was not displaced by a 28-fold excess of FA, and quenched roughly 80% of the initial fluorescence. Two-step binding kinetics were measured using the intrinsic fluorescence of the FBP tryptophan residues to give a <i>K</i>_D in the low nanomolar range for formation of the initial G5_Ac-COG-FA_1.0/FBP* complex, and a slow conversion to the tight complex formed between the dendrimer and the FBP exosite. The extent of quenching was sensitive to the choice of FA-dendrimer linker chemistry. Direct amide conjugation of FA to G5-PAMAM resulted in roughly 50% fluorescence quenching of the FBP. The G5_Ac-COG-FA, which has a longer linker containing a 1,2,3-triazole ring, exhibited an ∼80% fluorescence quenching. The binding of the G5_Ac-COG-FA_1.0 conjugate was compared to poly­(ethylene glycol) (PEG) conjugates of FA (PEG_<i>n</i>-FA). PEG_2k-FA had a binding strength similar to that of FA, whereas other PEG conjugates with higher molecular weight showed weaker binding. However, no PEG conjugates gave an increased degree of total fluorescence quenching

Conjugation Dependent Interaction of Folic Acid with Folate Binding Protein

Serum proteins play a critical role in the transport, uptake, and efficacy of targeted drug therapies, and here we investigate the interactions between folic acid–polymer conjugates and serum folate binding protein (FBP), the soluble form of the cellular membrane-bound folate receptor. We demonstrate that both choice of polymer and method of ligand conjugation affect the interactions between folic acid–polymer conjugates and serum FBP, resulting in changes in the folic acid-induced protein aggregation process. We have previously demonstrated that individual FBP molecules self-aggregate into nanoparticles at physiological concentrations. When poly­(amidoamine) dendrimer–folic acid conjugates bound to FBP, the distribution of nanoparticles was preserved. However, the dendritic conjugates produced larger nanoparticles than those formed in the presence of physiologically normal human levels of folic acid, and the conjugation method affected particle size distribution. In contrast, poly­(ethylene glycol)–folic acid conjugates demonstrated substantially reduced binding to FBP, did not cause folic acid-induced aggregation, and fully disrupted FBP self-aggregation. On the basis of these results, we discuss the potential implications for biodistribution, trafficking, and therapeutic efficacy of targeted nanoscale therapeutics, especially considering the widespread clinical use of poly­(ethylene glycol) conjugates. We highlight the importance of considering specific serum protein interactions in the rational design of similar nanocarrier systems. Our results suggest that prebinding therapeutic nanocarriers to serum FBP may allow folate-specific metabolic pathways to be exploited for delivery while also affording benefits of utilizing an endogenous protein as a vector