Nup358 is a protein subunit of the nuclear pore complex that recruits the opposing microtubule motors kinesin-1 and dynein [via the dynein adaptor Bicaudal D2 (BicD2)] to the nuclear envelope. This pathway is important for positioning of the nucleus during the early steps of mitotic spindle assembly and also essential for an important process in brain development. It is unknown whether dynein and kinesin-1 interact with Nup358 simultaneously or whether they compete. Here, we have reconstituted and characterized a minimal complex of kinesin-1 light chain 2 (KLC2) and Nup358. The proteins interact through a W-acidic motif in Nup358, which is highly conserved among vertebrates but absent in insects. While Nup358 and KLC2 form predominantly monomers, their interaction results in the formation of 2:2 complexes, and the W-acidic motif is required for the oligomerization. In active motor complexes, BicD2 and KLC2 each form dimers. Notably, we show that the dynein adaptor BicD2 and KLC2 interact simultaneously with Nup358, resulting in the formation of 2:2:2 complexes. Mutation of the W-acidic motif results in the formation of 1:1:1 complexes. On the basis of our data, we propose that Nup358 recruits simultaneously one kinesin-1 motor and one dynein motor via BicD2 to the nucleus. We hypothesize that the binding sites are close enough to promote direct interactions between these motor recognition domains, which may be important for the regulation of the motility of these opposing motors. Our data provide important insights into a nuclear positioning pathway that is crucial for brain development and faithful chromosome segregation.

As the human population grows, the anthropogenic impacts from various agricultural and industrial processes produce unwanted contaminants in the environment. The accurate, sensitive and rapid detection of such contaminants is vital for human health and safety. Surface-enhanced Raman spectroscopy (SERS) is a valuable analytical tool with wide applications in environmental contaminant monitoring. The aim of this review is to summarize recent advancements within SERS research as it applies to environmental detection, with a focus on research published or accessible from January 2021 through December 2021 including early-access publications. Our goal is to provide a wide breadth of information that can be used to provide background knowledge of the field, as well as inform and encourage further development of SERS techniques in protecting environmental quality and safety. Specifically, we highlight the characteristics of effective SERS nanosubstrates, and explore methods for the SERS detection of inorganic, organic, and biological contaminants including heavy metals, pharmaceuticals, plastic particles, synthetic dyes, pesticides, viruses, bacteria and mycotoxins. We also discuss the current limitations of SERS technologies in environmental detection and propose several avenues for future investigation. We encourage researchers to fill in the identified gaps so that SERS can be implemented in a real-world environment more effectively and efficiently, ultimately providing reliable and timely data to help and make science-based strategies and policies to protect environmental safety and public health.

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Due to their wider spread, higher concentrations, and bioavailability, nanoplastics (nPs) pose great ecological hazards both in the marine and freshwater ecosystems. To evaluate their toxicity in the model freshwater organism Daphnia magna, and how the nPs how the particles translocate from the intestine, the primary organ of accumulation, to the other body parts, is an important phenomenon. In the current effort, we addressed the phenomenon of inner organ translocation of the nPs and suggested plausible mechanism of the process with the help of a model nPS and confocal surface-enhances Raman mapping. We synthesized a polystyrene coated-nanogold ‘core-shell' particle (nPS@nAu), conjugated with a Raman reporter, 4-mercapto benzoic acid to the (4-MBA). This dual functional model nanoplastic (model nPS) fulfills the purpose of nP as well as surface-enhanced Raman scattering (SERS) nano-probe. Upon exposure, the Daphnia showed uptake of the model nPSs mainly in the intestine tract. Further exposure (beyond 4 h at model nPS concentration of 10 mg/L) exhibited inter organ migration of the model nPSs to other parts in the Daphnia body. Translocation of the model nPSs was observed with the help of multilayer stack Raman mapping of the SERS signals coming from the model nPSs.