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RNA silencing pathways are complex, highly conserved, and perform widespread, critical regulatory roles. In C. elegans germlines, RNA surveillance occurs through a series of perinuclear germ granule compartments - P granules, Z granules, SIMR foci, and Mutator foci - multiple of which form via phase separation and exhibit liquid-like properties. The functions of individual proteins within germ granules are well-studied, but the spatial organization, physical interaction, and coordination of biomolecule exchange between compartments within germ granule, nuage, is less understood. Here we find that key proteins are sufficient for compartment separation, and that the boundary between compartments can be reestablished after perturbation. Using super-resolution microscopy, we discover a toroidal P granule morphology which encircles the other germ granule compartments in a consistent exterior-to-interior spatial organization. Combined with findings that nuclear pores primarily interact with P granules, this nuage compartment organization has broad implications for the trajectory of an RNA as it exits the nucleus and enters small RNA pathway compartments. Furthermore, we quantify the stoichiometric relationships between germ granule compartments and RNA to reveal discrete populations of nuage that differentially associate with RNAi-targeted transcripts, possibly suggesting functional differences between nuage configurations. Together, our work creates a more spatially and compositionally accurate model of C. elegans nuage which informs the conceptualization of RNA silencing through different germ granule compartments.

Electromagnetic Interference contributes to a significant percentage of failures in the verification stage of automotive electronics design cycle. Today these issues are caught late in the design cycle leading to delay in time-to-market. An effective simulation methodology is key to catching the problems at an early design stage. However, accurate system-level analysis is time intensive. This letter presents a model-based simulation methodology for system-level immunity characterization at an early design stage. The simulation framework is comprised of a hybrid 2D-3D electromagnetic solver and a circuit solver. IC immunity model (ICIM) is inducted into the simulation environment to accurately predict the immunity behavior in a Bulk Current Injection (BCI) test. The proposed method is validated by comparing the simulation prediction with the actual BCI measurement. Further, layout changes are made based on simulation to mitigate the measurement failure. This emphasizes the use of model-based simulation to predict immunity performance at early product design cycle.

Proximity labeling (PL) catalyzed by promiscuous enzymes such as TurboID have enabled the proteomic analysis of subcellular regions difficult or impossible to access by conventional fractionation-based approaches. Yet some cellular regions, such as organelle contact sites, remain out of reach for current PL methods. To address this limitation, we split the enzyme TurboID into two inactive fragments that recombine when driven together by a protein-protein interaction or membrane-membrane apposition. At endoplasmic reticulum (ER)-mitochondria contact sites, reconstituted TurboID catalyzed spatially-restricted biotinylation, enabling the enrichment and identification of >100 endogenous proteins, including many not previously linked to ER-mitochondria contacts. We validated eight novel candidates by biochemical fractionation and overexpression imaging. Overall, split-TurboID is a versatile tool for conditional and spatially-specific proximity labeling in cells.

The advent of smart wearable technology in recent years has seen applications which bridge the gap between diverse aspects of day-to-day life. Navigation as one of its feature, while providing convenience to a large degree, has a reputation for quick battery drainage. This paper proposes to alleviate this issue with a simplistic approach to navigation on a smart wearable. The proposed method also aims to provide real-time orientation based directions to the user with a compass-like feature. It accomplishes these functionalities by relying on the GPS module already present on the smartphone, route-mapping done on the Android application and a strong Bluetooth connection with the wearable. The final step of orientation based navigation is alone computed on the wearable before being displayed. Yet another computation heavy aspect of navigation on a wearable has to do with displaying a miniaturized map on the screen. This was replaced by displaying the directions in the form of simple arrow pointers. The smart wearable is designed to be worn on the wrist and is intended to be an essential tool for drivers and pedestrians as directions will be clearly visible in their line of sight while they are driving or walking. The design is also highly cost effective, appealing to a larger population as an alternative to the existing products of similar kind. A hardware prototype of the smart wearable is described and the algorithmic implementation of the method is discussed.

In the Caenorhabditis elegans germline, fem-3 Binding Factor (FBF) partners with LST-1 to maintain stem cells. A crystal structure of an FBF-2/LST-1/RNA complex revealed that FBF-2 recognizes a short RNA motif different from the characteristic 9-nt FBF binding element, and compact motif recognition coincided with curvature changes in the FBF-2 scaffold. Previously, we engineered FBF-2 to favor recognition of shorter RNA motifs without curvature change (Bhat et al., 2019). In vitro selection of RNAs bound by FBF-2 suggested sequence specificity in the central region of the compact element. This bias, reflected in the crystal structure, was validated in RNA-binding assays. FBF-2 has the intrinsic ability to bind to this shorter motif. LST-1 weakens FBF-2 binding affinity for short and long motifs, which may increase target selectivity. Our findings highlight the role of FBF scaffold flexibility in RNA recognition and suggest a new mechanism by which protein partners refine target site selection.