Combining DNA scaffolds and acoustic force spectroscopy to characterize individual protein bonds.

Single-molecule data are of great significance in biology, chemistry, and medicine. However, new experimental tools to characterize, in a multiplexed manner, protein bond rupture under force are still needed. Acoustic force spectroscopy is an emerging manipulation technique which generates acoustic waves to apply force in parallel on multiple microbeads tethered to a surface. We here exploit this configuration in combination with the recently developed modular junctured-DNA scaffold that has been designed to study protein-protein interactions at the single-molecule level. By applying repetitive constant force steps on the FKBP12-rapamycin-FRB complex, we measure its unbinding kinetics under force at the single-bond level. Special efforts are made in analyzing the data to identify potential pitfalls. We propose a calibration method allowing in situ force determination during the course of the unbinding measurement. We compare our results with well-established techniques, such as magnetic tweezers, to ensure their accuracy. We also apply our strategy to study the force-dependent rupture of a single-domain antibody with its antigen. Overall, we get a good agreement with the published parameters that have been obtained at zero force and population level. Thus, our technique offers single-molecule precision for multiplexed measurements of interactions of biotechnological and medical interest.

The role of gender in Zika prevention behaviors in the Dominican Republic: Findings and programmatic implications from a qualitative study.

BACKGROUND: Zika remains an epidemiological threat in Latin America, including the Dominican Republic. Although transmitted by the same mosquito as Dengue and Chikungunya, Zika is unique in the potentially harmful consequences for babies born to women infected during pregnancy. Experts highlight the feminization of Zika, in terms of burden of disease and women's caregiving responsibilities. Understanding gender's role in Zika prevention, therefore, is key to strengthening current and future programs. METHODOLOGY/PRINCIPAL FINDINGS: This qualitative study, comprised of 12 focus group discussions and eight in-depth interviews, explored gender's role in Zika among pregnant and non-pregnant women as well as male partners of pregnant women in the Dominican Republic. Topics included perceptions about Zika and perceived feasibility and effectiveness of prevention behaviors (e.g. cleaning water storage containers, using condoms during pregnancy). Researchers applied grounded theory through a process of deductive coding-classifying data around predetermined categories-followed by inductive coding-identifying themes that emerged from coded data. Study findings uncovered three ways in which gender may influence Zika prevention. First, women are largely responsible for household chores-including cleaning water storage containers-with men as assistants. Second, men described their role in the family as the protector. Finally, men and women believed that partners would perceive suggesting condom use or abstinence during pregnancy as a sign of infidelity. CONCLUSIONS: Current/future Zika programs should address knowledge gaps, especially around water storage cleaning techniques and sexual transmission. Programs should also integrate gender into programming in culturally-relevant ways that avoid reinforcing stereotypes. Furthermore, programs should tailor activities for men, women, as well as the couple. In the end, integrating gender in a way that is mindful of the local context while not exploiting existing gender roles is critical for preventing Zika and similar mosquito-borne diseases, both in the Dominican Republic and throughout the region.